First commit

middleware/commands.go

@@ -0,0 +1,120 @@
+package middleware
+
+import (
+	"errors"
+	"runtime"
+	"unicode"
+
+	"github.com/flynn/go-shlex"
+)
+
+var runtimeGoos = runtime.GOOS
+
+// SplitCommandAndArgs takes a command string and parses it
+// shell-style into the command and its separate arguments.
+func SplitCommandAndArgs(command string) (cmd string, args []string, err error) {
+	var parts []string
+
+	if runtimeGoos == "windows" {
+		parts = parseWindowsCommand(command) // parse it Windows-style
+	} else {
+		parts, err = parseUnixCommand(command) // parse it Unix-style
+		if err != nil {
+			err = errors.New("error parsing command: " + err.Error())
+			return
+		}
+	}
+
+	if len(parts) == 0 {
+		err = errors.New("no command contained in '" + command + "'")
+		return
+	}
+
+	cmd = parts[0]
+	if len(parts) > 1 {
+		args = parts[1:]
+	}
+
+	return
+}
+
+// parseUnixCommand parses a unix style command line and returns the
+// command and its arguments or an error
+func parseUnixCommand(cmd string) ([]string, error) {
+	return shlex.Split(cmd)
+}
+
+// parseWindowsCommand parses windows command lines and
+// returns the command and the arguments as an array. It
+// should be able to parse commonly used command lines.
+// Only basic syntax is supported:
+//  - spaces in double quotes are not token delimiters
+//  - double quotes are escaped by either backspace or another double quote
+//  - except for the above case backspaces are path separators (not special)
+//
+// Many sources point out that escaping quotes using backslash can be unsafe.
+// Use two double quotes when possible. (Source: http://stackoverflow.com/a/31413730/2616179 )
+//
+// This function has to be used on Windows instead
+// of the shlex package because this function treats backslash
+// characters properly.
+func parseWindowsCommand(cmd string) []string {
+	const backslash = '\\'
+	const quote = '"'
+
+	var parts []string
+	var part string
+	var inQuotes bool
+	var lastRune rune
+
+	for i, ch := range cmd {
+
+		if i != 0 {
+			lastRune = rune(cmd[i-1])
+		}
+
+		if ch == backslash {
+			// put it in the part - for now we don't know if it's an
+			// escaping char or path separator
+			part += string(ch)
+			continue
+		}
+
+		if ch == quote {
+			if lastRune == backslash {
+				// remove the backslash from the part and add the escaped quote instead
+				part = part[:len(part)-1]
+				part += string(ch)
+				continue
+			}
+
+			if lastRune == quote {
+				// revert the last change of the inQuotes state
+				// it was an escaping quote
+				inQuotes = !inQuotes
+				part += string(ch)
+				continue
+			}
+
+			// normal escaping quotes
+			inQuotes = !inQuotes
+			continue
+
+		}
+
+		if unicode.IsSpace(ch) && !inQuotes && len(part) > 0 {
+			parts = append(parts, part)
+			part = ""
+			continue
+		}
+
+		part += string(ch)
+	}
+
+	if len(part) > 0 {
+		parts = append(parts, part)
+		part = ""
+	}
+
+	return parts
+}

middleware/commands_test.go

@@ -0,0 +1,291 @@
+package middleware
+
+import (
+	"fmt"
+	"runtime"
+	"strings"
+	"testing"
+)
+
+func TestParseUnixCommand(t *testing.T) {
+	tests := []struct {
+		input    string
+		expected []string
+	}{
+		// 0 - emtpy command
+		{
+			input:    ``,
+			expected: []string{},
+		},
+		// 1 - command without arguments
+		{
+			input:    `command`,
+			expected: []string{`command`},
+		},
+		// 2 - command with single argument
+		{
+			input:    `command arg1`,
+			expected: []string{`command`, `arg1`},
+		},
+		// 3 - command with multiple arguments
+		{
+			input:    `command arg1 arg2`,
+			expected: []string{`command`, `arg1`, `arg2`},
+		},
+		// 4 - command with single argument with space character - in quotes
+		{
+			input:    `command "arg1 arg1"`,
+			expected: []string{`command`, `arg1 arg1`},
+		},
+		// 5 - command with multiple spaces and tab character
+		{
+			input:    "command arg1    arg2\targ3",
+			expected: []string{`command`, `arg1`, `arg2`, `arg3`},
+		},
+		// 6 - command with single argument with space character - escaped with backspace
+		{
+			input:    `command arg1\ arg2`,
+			expected: []string{`command`, `arg1 arg2`},
+		},
+		// 7 - single quotes should escape special chars
+		{
+			input:    `command 'arg1\ arg2'`,
+			expected: []string{`command`, `arg1\ arg2`},
+		},
+	}
+
+	for i, test := range tests {
+		errorPrefix := fmt.Sprintf("Test [%d]: ", i)
+		errorSuffix := fmt.Sprintf(" Command to parse: [%s]", test.input)
+		actual, _ := parseUnixCommand(test.input)
+		if len(actual) != len(test.expected) {
+			t.Errorf(errorPrefix+"Expected %d parts, got %d: %#v."+errorSuffix, len(test.expected), len(actual), actual)
+			continue
+		}
+		for j := 0; j < len(actual); j++ {
+			if expectedPart, actualPart := test.expected[j], actual[j]; expectedPart != actualPart {
+				t.Errorf(errorPrefix+"Expected: %v Actual: %v (index %d)."+errorSuffix, expectedPart, actualPart, j)
+			}
+		}
+	}
+}
+
+func TestParseWindowsCommand(t *testing.T) {
+	tests := []struct {
+		input    string
+		expected []string
+	}{
+		{ // 0 - empty command - do not fail
+			input:    ``,
+			expected: []string{},
+		},
+		{ // 1 - cmd without args
+			input:    `cmd`,
+			expected: []string{`cmd`},
+		},
+		{ // 2 - multiple args
+			input:    `cmd arg1 arg2`,
+			expected: []string{`cmd`, `arg1`, `arg2`},
+		},
+		{ // 3 - multiple args with space
+			input:    `cmd "combined arg" arg2`,
+			expected: []string{`cmd`, `combined arg`, `arg2`},
+		},
+		{ // 4 - path without spaces
+			input:    `mkdir C:\Windows\foo\bar`,
+			expected: []string{`mkdir`, `C:\Windows\foo\bar`},
+		},
+		{ // 5 - command with space in quotes
+			input:    `"command here"`,
+			expected: []string{`command here`},
+		},
+		{ // 6 - argument with escaped quotes (two quotes)
+			input:    `cmd ""arg""`,
+			expected: []string{`cmd`, `"arg"`},
+		},
+		{ // 7 - argument with escaped quotes (backslash)
+			input:    `cmd \"arg\"`,
+			expected: []string{`cmd`, `"arg"`},
+		},
+		{ // 8 - two quotes (escaped) inside an inQuote element
+			input:    `cmd "a ""quoted value"`,
+			expected: []string{`cmd`, `a "quoted value`},
+		},
+		// TODO - see how many quotes are dislayed if we use "", """, """""""
+		{ // 9 - two quotes outside an inQuote element
+			input:    `cmd a ""quoted value`,
+			expected: []string{`cmd`, `a`, `"quoted`, `value`},
+		},
+		{ // 10 - path with space in quotes
+			input:    `mkdir "C:\directory name\foobar"`,
+			expected: []string{`mkdir`, `C:\directory name\foobar`},
+		},
+		{ // 11 - space without quotes
+			input:    `mkdir C:\ space`,
+			expected: []string{`mkdir`, `C:\`, `space`},
+		},
+		{ // 12 - space in quotes
+			input:    `mkdir "C:\ space"`,
+			expected: []string{`mkdir`, `C:\ space`},
+		},
+		{ // 13 - UNC
+			input:    `mkdir \\?\C:\Users`,
+			expected: []string{`mkdir`, `\\?\C:\Users`},
+		},
+		{ // 14 - UNC with space
+			input:    `mkdir "\\?\C:\Program Files"`,
+			expected: []string{`mkdir`, `\\?\C:\Program Files`},
+		},
+
+		{ // 15 - unclosed quotes - treat as if the path ends with quote
+			input:    `mkdir "c:\Program files`,
+			expected: []string{`mkdir`, `c:\Program files`},
+		},
+		{ // 16 - quotes used inside the argument
+			input:    `mkdir "c:\P"rogra"m f"iles`,
+			expected: []string{`mkdir`, `c:\Program files`},
+		},
+	}
+
+	for i, test := range tests {
+		errorPrefix := fmt.Sprintf("Test [%d]: ", i)
+		errorSuffix := fmt.Sprintf(" Command to parse: [%s]", test.input)
+
+		actual := parseWindowsCommand(test.input)
+		if len(actual) != len(test.expected) {
+			t.Errorf(errorPrefix+"Expected %d parts, got %d: %#v."+errorSuffix, len(test.expected), len(actual), actual)
+			continue
+		}
+		for j := 0; j < len(actual); j++ {
+			if expectedPart, actualPart := test.expected[j], actual[j]; expectedPart != actualPart {
+				t.Errorf(errorPrefix+"Expected: %v Actual: %v (index %d)."+errorSuffix, expectedPart, actualPart, j)
+			}
+		}
+	}
+}
+
+func TestSplitCommandAndArgs(t *testing.T) {
+
+	// force linux parsing. It's more robust and covers error cases
+	runtimeGoos = "linux"
+	defer func() {
+		runtimeGoos = runtime.GOOS
+	}()
+
+	var parseErrorContent = "error parsing command:"
+	var noCommandErrContent = "no command contained in"
+
+	tests := []struct {
+		input              string
+		expectedCommand    string
+		expectedArgs       []string
+		expectedErrContent string
+	}{
+		// 0 - emtpy command
+		{
+			input:              ``,
+			expectedCommand:    ``,
+			expectedArgs:       nil,
+			expectedErrContent: noCommandErrContent,
+		},
+		// 1 - command without arguments
+		{
+			input:              `command`,
+			expectedCommand:    `command`,
+			expectedArgs:       nil,
+			expectedErrContent: ``,
+		},
+		// 2 - command with single argument
+		{
+			input:              `command arg1`,
+			expectedCommand:    `command`,
+			expectedArgs:       []string{`arg1`},
+			expectedErrContent: ``,
+		},
+		// 3 - command with multiple arguments
+		{
+			input:              `command arg1 arg2`,
+			expectedCommand:    `command`,
+			expectedArgs:       []string{`arg1`, `arg2`},
+			expectedErrContent: ``,
+		},
+		// 4 - command with unclosed quotes
+		{
+			input:              `command "arg1 arg2`,
+			expectedCommand:    "",
+			expectedArgs:       nil,
+			expectedErrContent: parseErrorContent,
+		},
+		// 5 - command with unclosed quotes
+		{
+			input:              `command 'arg1 arg2"`,
+			expectedCommand:    "",
+			expectedArgs:       nil,
+			expectedErrContent: parseErrorContent,
+		},
+	}
+
+	for i, test := range tests {
+		errorPrefix := fmt.Sprintf("Test [%d]: ", i)
+		errorSuffix := fmt.Sprintf(" Command to parse: [%s]", test.input)
+		actualCommand, actualArgs, actualErr := SplitCommandAndArgs(test.input)
+
+		// test if error matches expectation
+		if test.expectedErrContent != "" {
+			if actualErr == nil {
+				t.Errorf(errorPrefix+"Expected error with content [%s], found no error."+errorSuffix, test.expectedErrContent)
+			} else if !strings.Contains(actualErr.Error(), test.expectedErrContent) {
+				t.Errorf(errorPrefix+"Expected error with content [%s], found [%v]."+errorSuffix, test.expectedErrContent, actualErr)
+			}
+		} else if actualErr != nil {
+			t.Errorf(errorPrefix+"Expected no error, found [%v]."+errorSuffix, actualErr)
+		}
+
+		// test if command matches
+		if test.expectedCommand != actualCommand {
+			t.Errorf(errorPrefix+"Expected command: [%s], actual: [%s]."+errorSuffix, test.expectedCommand, actualCommand)
+		}
+
+		// test if arguments match
+		if len(test.expectedArgs) != len(actualArgs) {
+			t.Errorf(errorPrefix+"Wrong number of arguments! Expected [%v], actual [%v]."+errorSuffix, test.expectedArgs, actualArgs)
+		} else {
+			// test args only if the count matches.
+			for j, actualArg := range actualArgs {
+				expectedArg := test.expectedArgs[j]
+				if actualArg != expectedArg {
+					t.Errorf(errorPrefix+"Argument at position [%d] differ! Expected [%s], actual [%s]"+errorSuffix, j, expectedArg, actualArg)
+				}
+			}
+		}
+	}
+}
+
+func ExampleSplitCommandAndArgs() {
+	var commandLine string
+	var command string
+	var args []string
+
+	// just for the test - change GOOS and reset it at the end of the test
+	runtimeGoos = "windows"
+	defer func() {
+		runtimeGoos = runtime.GOOS
+	}()
+
+	commandLine = `mkdir /P "C:\Program Files"`
+	command, args, _ = SplitCommandAndArgs(commandLine)
+
+	fmt.Printf("Windows: %s: %s [%s]\n", commandLine, command, strings.Join(args, ","))
+
+	// set GOOS to linux
+	runtimeGoos = "linux"
+
+	commandLine = `mkdir -p /path/with\ space`
+	command, args, _ = SplitCommandAndArgs(commandLine)
+
+	fmt.Printf("Linux: %s: %s [%s]\n", commandLine, command, strings.Join(args, ","))
+
+	// Output:
+	// Windows: mkdir /P "C:\Program Files": mkdir [/P,C:\Program Files]
+	// Linux: mkdir -p /path/with\ space: mkdir [-p,/path/with space]
+}

middleware/context.go

@@ -0,0 +1,135 @@
+package middleware
+
+import (
+	"net"
+	"net/http"
+	"strings"
+	"time"
+
+	"github.com/miekg/dns"
+)
+
+// This file contains the context and functions available for
+// use in the templates.
+
+// Context is the context with which Caddy templates are executed.
+type Context struct {
+	Root http.FileSystem // TODO(miek): needed
+	Req  *dns.Msg
+	W    dns.ResponseWriter
+}
+
+// Now returns the current timestamp in the specified format.
+func (c Context) Now(format string) string {
+	return time.Now().Format(format)
+}
+
+// NowDate returns the current date/time that can be used
+// in other time functions.
+func (c Context) NowDate() time.Time {
+	return time.Now()
+}
+
+// Header gets the value of a header.
+func (c Context) Header() *dns.RR_Header {
+	// TODO(miek)
+	return nil
+}
+
+// IP gets the (remote) IP address of the client making the request.
+func (c Context) IP() string {
+	ip, _, err := net.SplitHostPort(c.W.RemoteAddr().String())
+	if err != nil {
+		return c.W.RemoteAddr().String()
+	}
+	return ip
+}
+
+// Post gets the (remote) Port of the client making the request.
+func (c Context) Port() (string, error) {
+	_, port, err := net.SplitHostPort(c.W.RemoteAddr().String())
+	if err != nil {
+		return "0", err
+	}
+	return port, nil
+}
+
+// Proto gets the protocol used as the transport. This
+// will be udp or tcp.
+func (c Context) Proto() string {
+	if _, ok := c.W.RemoteAddr().(*net.UDPAddr); ok {
+		return "udp"
+	}
+	if _, ok := c.W.RemoteAddr().(*net.TCPAddr); ok {
+		return "tcp"
+	}
+	return "udp"
+}
+
+// Family returns the family of the transport.
+// 1 for IPv4 and 2 for IPv6.
+func (c Context) Family() int {
+	var a net.IP
+	ip := c.W.RemoteAddr()
+	if i, ok := ip.(*net.UDPAddr); ok {
+		a = i.IP
+	}
+	if i, ok := ip.(*net.TCPAddr); ok {
+		a = i.IP
+	}
+
+	if a.To4() != nil {
+		return 1
+	}
+	return 2
+}
+
+// Type returns the type of the question as a string.
+func (c Context) Type() string {
+	return dns.Type(c.Req.Question[0].Qtype).String()
+}
+
+// QType returns the type of the question as a uint16.
+func (c Context) QType() uint16 {
+	return c.Req.Question[0].Qtype
+}
+
+// Name returns the name of the question in the request. Note
+// this name will always have a closing dot and will be lower cased.
+func (c Context) Name() string {
+	return strings.ToLower(dns.Name(c.Req.Question[0].Name).String())
+}
+
+// QName returns the name of the question in the request.
+func (c Context) QName() string {
+	return dns.Name(c.Req.Question[0].Name).String()
+}
+
+// Class returns the class of the question in the request.
+func (c Context) Class() string {
+	return dns.Class(c.Req.Question[0].Qclass).String()
+}
+
+// QClass returns the class of the question in the request.
+func (c Context) QClass() uint16 {
+	return c.Req.Question[0].Qclass
+}
+
+// More convience types for extracting stuff from a message?
+// Header?
+
+// ErrorMessage returns an error message suitable for sending
+// back to the client.
+func (c Context) ErrorMessage(rcode int) *dns.Msg {
+	m := new(dns.Msg)
+	m.SetRcode(c.Req, rcode)
+	return m
+}
+
+// AnswerMessage returns an error message suitable for sending
+// back to the client.
+func (c Context) AnswerMessage() *dns.Msg {
+	m := new(dns.Msg)
+	m.SetReply(c.Req)
+	return m
+}

middleware/context_test.go

@@ -0,0 +1,613 @@
+package middleware
+
+import (
+	"bytes"
+	"fmt"
+	"io/ioutil"
+	"net/http"
+	"net/url"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+	"time"
+)
+
+func TestInclude(t *testing.T) {
+	context := getContextOrFail(t)
+
+	inputFilename := "test_file"
+	absInFilePath := filepath.Join(fmt.Sprintf("%s", context.Root), inputFilename)
+	defer func() {
+		err := os.Remove(absInFilePath)
+		if err != nil && !os.IsNotExist(err) {
+			t.Fatalf("Failed to clean test file!")
+		}
+	}()
+
+	tests := []struct {
+		fileContent          string
+		expectedContent      string
+		shouldErr            bool
+		expectedErrorContent string
+	}{
+		// Test 0 - all good
+		{
+			fileContent:          `str1 {{ .Root }} str2`,
+			expectedContent:      fmt.Sprintf("str1 %s str2", context.Root),
+			shouldErr:            false,
+			expectedErrorContent: "",
+		},
+		// Test 1 - failure on template.Parse
+		{
+			fileContent:          `str1 {{ .Root } str2`,
+			expectedContent:      "",
+			shouldErr:            true,
+			expectedErrorContent: `unexpected "}" in operand`,
+		},
+		// Test 3 - failure on template.Execute
+		{
+			fileContent:          `str1 {{ .InvalidField }} str2`,
+			expectedContent:      "",
+			shouldErr:            true,
+			expectedErrorContent: `InvalidField is not a field of struct type middleware.Context`,
+		},
+	}
+
+	for i, test := range tests {
+		testPrefix := getTestPrefix(i)
+
+		// WriteFile truncates the contentt
+		err := ioutil.WriteFile(absInFilePath, []byte(test.fileContent), os.ModePerm)
+		if err != nil {
+			t.Fatal(testPrefix+"Failed to create test file. Error was: %v", err)
+		}
+
+		content, err := context.Include(inputFilename)
+		if err != nil {
+			if !test.shouldErr {
+				t.Errorf(testPrefix+"Expected no error, found [%s]", test.expectedErrorContent, err.Error())
+			}
+			if !strings.Contains(err.Error(), test.expectedErrorContent) {
+				t.Errorf(testPrefix+"Expected error content [%s], found [%s]", test.expectedErrorContent, err.Error())
+			}
+		}
+
+		if err == nil && test.shouldErr {
+			t.Errorf(testPrefix+"Expected error [%s] but found nil. Input file was: %s", test.expectedErrorContent, inputFilename)
+		}
+
+		if content != test.expectedContent {
+			t.Errorf(testPrefix+"Expected content [%s] but found [%s]. Input file was: %s", test.expectedContent, content, inputFilename)
+		}
+	}
+}
+
+func TestIncludeNotExisting(t *testing.T) {
+	context := getContextOrFail(t)
+
+	_, err := context.Include("not_existing")
+	if err == nil {
+		t.Errorf("Expected error but found nil!")
+	}
+}
+
+func TestMarkdown(t *testing.T) {
+	context := getContextOrFail(t)
+
+	inputFilename := "test_file"
+	absInFilePath := filepath.Join(fmt.Sprintf("%s", context.Root), inputFilename)
+	defer func() {
+		err := os.Remove(absInFilePath)
+		if err != nil && !os.IsNotExist(err) {
+			t.Fatalf("Failed to clean test file!")
+		}
+	}()
+
+	tests := []struct {
+		fileContent     string
+		expectedContent string
+	}{
+		// Test 0 - test parsing of markdown
+		{
+			fileContent:     "* str1\n* str2\n",
+			expectedContent: "<ul>\n<li>str1</li>\n<li>str2</li>\n</ul>\n",
+		},
+	}
+
+	for i, test := range tests {
+		testPrefix := getTestPrefix(i)
+
+		// WriteFile truncates the contentt
+		err := ioutil.WriteFile(absInFilePath, []byte(test.fileContent), os.ModePerm)
+		if err != nil {
+			t.Fatal(testPrefix+"Failed to create test file. Error was: %v", err)
+		}
+
+		content, _ := context.Markdown(inputFilename)
+		if content != test.expectedContent {
+			t.Errorf(testPrefix+"Expected content [%s] but found [%s]. Input file was: %s", test.expectedContent, content, inputFilename)
+		}
+	}
+}
+
+func TestCookie(t *testing.T) {
+
+	tests := []struct {
+		cookie        *http.Cookie
+		cookieName    string
+		expectedValue string
+	}{
+		// Test 0 - happy path
+		{
+			cookie:        &http.Cookie{Name: "cookieName", Value: "cookieValue"},
+			cookieName:    "cookieName",
+			expectedValue: "cookieValue",
+		},
+		// Test 1 - try to get a non-existing cookie
+		{
+			cookie:        &http.Cookie{Name: "cookieName", Value: "cookieValue"},
+			cookieName:    "notExisting",
+			expectedValue: "",
+		},
+		// Test 2 - partial name match
+		{
+			cookie:        &http.Cookie{Name: "cookie", Value: "cookieValue"},
+			cookieName:    "cook",
+			expectedValue: "",
+		},
+		// Test 3 - cookie with optional fields
+		{
+			cookie:        &http.Cookie{Name: "cookie", Value: "cookieValue", Path: "/path", Domain: "https://localhost", Expires: (time.Now().Add(10 * time.Minute)), MaxAge: 120},
+			cookieName:    "cookie",
+			expectedValue: "cookieValue",
+		},
+	}
+
+	for i, test := range tests {
+		testPrefix := getTestPrefix(i)
+
+		// reinitialize the context for each test
+		context := getContextOrFail(t)
+
+		context.Req.AddCookie(test.cookie)
+
+		actualCookieVal := context.Cookie(test.cookieName)
+
+		if actualCookieVal != test.expectedValue {
+			t.Errorf(testPrefix+"Expected cookie value [%s] but found [%s] for cookie with name %s", test.expectedValue, actualCookieVal, test.cookieName)
+		}
+	}
+}
+
+func TestCookieMultipleCookies(t *testing.T) {
+	context := getContextOrFail(t)
+
+	cookieNameBase, cookieValueBase := "cookieName", "cookieValue"
+
+	// make sure that there's no state and multiple requests for different cookies return the correct result
+	for i := 0; i < 10; i++ {
+		context.Req.AddCookie(&http.Cookie{Name: fmt.Sprintf("%s%d", cookieNameBase, i), Value: fmt.Sprintf("%s%d", cookieValueBase, i)})
+	}
+
+	for i := 0; i < 10; i++ {
+		expectedCookieVal := fmt.Sprintf("%s%d", cookieValueBase, i)
+		actualCookieVal := context.Cookie(fmt.Sprintf("%s%d", cookieNameBase, i))
+		if actualCookieVal != expectedCookieVal {
+			t.Fatalf("Expected cookie value %s, found %s", expectedCookieVal, actualCookieVal)
+		}
+	}
+}
+
+func TestHeader(t *testing.T) {
+	context := getContextOrFail(t)
+
+	headerKey, headerVal := "Header1", "HeaderVal1"
+	context.Req.Header.Add(headerKey, headerVal)
+
+	actualHeaderVal := context.Header(headerKey)
+	if actualHeaderVal != headerVal {
+		t.Errorf("Expected header %s, found %s", headerVal, actualHeaderVal)
+	}
+
+	missingHeaderVal := context.Header("not-existing")
+	if missingHeaderVal != "" {
+		t.Errorf("Expected empty header value, found %s", missingHeaderVal)
+	}
+}
+
+func TestIP(t *testing.T) {
+	context := getContextOrFail(t)
+
+	tests := []struct {
+		inputRemoteAddr string
+		expectedIP      string
+	}{
+		// Test 0 - ipv4 with port
+		{"1.1.1.1:1111", "1.1.1.1"},
+		// Test 1 - ipv4 without port
+		{"1.1.1.1", "1.1.1.1"},
+		// Test 2 - ipv6 with port
+		{"[::1]:11", "::1"},
+		// Test 3 - ipv6 without port and brackets
+		{"[2001:db8:a0b:12f0::1]", "[2001:db8:a0b:12f0::1]"},
+		// Test 4 - ipv6 with zone and port
+		{`[fe80:1::3%eth0]:44`, `fe80:1::3%eth0`},
+	}
+
+	for i, test := range tests {
+		testPrefix := getTestPrefix(i)
+
+		context.Req.RemoteAddr = test.inputRemoteAddr
+		actualIP := context.IP()
+
+		if actualIP != test.expectedIP {
+			t.Errorf(testPrefix+"Expected IP %s, found %s", test.expectedIP, actualIP)
+		}
+	}
+}
+
+func TestURL(t *testing.T) {
+	context := getContextOrFail(t)
+
+	inputURL := "http://localhost"
+	context.Req.RequestURI = inputURL
+
+	if inputURL != context.URI() {
+		t.Errorf("Expected url %s, found %s", inputURL, context.URI())
+	}
+}
+
+func TestHost(t *testing.T) {
+	tests := []struct {
+		input        string
+		expectedHost string
+		shouldErr    bool
+	}{
+		{
+			input:        "localhost:123",
+			expectedHost: "localhost",
+			shouldErr:    false,
+		},
+		{
+			input:        "localhost",
+			expectedHost: "localhost",
+			shouldErr:    false,
+		},
+		{
+			input:        "[::]",
+			expectedHost: "",
+			shouldErr:    true,
+		},
+	}
+
+	for _, test := range tests {
+		testHostOrPort(t, true, test.input, test.expectedHost, test.shouldErr)
+	}
+}
+
+func TestPort(t *testing.T) {
+	tests := []struct {
+		input        string
+		expectedPort string
+		shouldErr    bool
+	}{
+		{
+			input:        "localhost:123",
+			expectedPort: "123",
+			shouldErr:    false,
+		},
+		{
+			input:        "localhost",
+			expectedPort: "80", // assuming 80 is the default port
+			shouldErr:    false,
+		},
+		{
+			input:        ":8080",
+			expectedPort: "8080",
+			shouldErr:    false,
+		},
+		{
+			input:        "[::]",
+			expectedPort: "",
+			shouldErr:    true,
+		},
+	}
+
+	for _, test := range tests {
+		testHostOrPort(t, false, test.input, test.expectedPort, test.shouldErr)
+	}
+}
+
+func testHostOrPort(t *testing.T, isTestingHost bool, input, expectedResult string, shouldErr bool) {
+	context := getContextOrFail(t)
+
+	context.Req.Host = input
+	var actualResult, testedObject string
+	var err error
+
+	if isTestingHost {
+		actualResult, err = context.Host()
+		testedObject = "host"
+	} else {
+		actualResult, err = context.Port()
+		testedObject = "port"
+	}
+
+	if shouldErr && err == nil {
+		t.Errorf("Expected error, found nil!")
+		return
+	}
+
+	if !shouldErr && err != nil {
+		t.Errorf("Expected no error, found %s", err)
+		return
+	}
+
+	if actualResult != expectedResult {
+		t.Errorf("Expected %s %s, found %s", testedObject, expectedResult, actualResult)
+	}
+}
+
+func TestMethod(t *testing.T) {
+	context := getContextOrFail(t)
+
+	method := "POST"
+	context.Req.Method = method
+
+	if method != context.Method() {
+		t.Errorf("Expected method %s, found %s", method, context.Method())
+	}
+
+}
+
+func TestPathMatches(t *testing.T) {
+	context := getContextOrFail(t)
+
+	tests := []struct {
+		urlStr      string
+		pattern     string
+		shouldMatch bool
+	}{
+		// Test 0
+		{
+			urlStr:      "http://localhost/",
+			pattern:     "",
+			shouldMatch: true,
+		},
+		// Test 1
+		{
+			urlStr:      "http://localhost",
+			pattern:     "",
+			shouldMatch: true,
+		},
+		// Test 1
+		{
+			urlStr:      "http://localhost/",
+			pattern:     "/",
+			shouldMatch: true,
+		},
+		// Test 3
+		{
+			urlStr:      "http://localhost/?param=val",
+			pattern:     "/",
+			shouldMatch: true,
+		},
+		// Test 4
+		{
+			urlStr:      "http://localhost/dir1/dir2",
+			pattern:     "/dir2",
+			shouldMatch: false,
+		},
+		// Test 5
+		{
+			urlStr:      "http://localhost/dir1/dir2",
+			pattern:     "/dir1",
+			shouldMatch: true,
+		},
+		// Test 6
+		{
+			urlStr:      "http://localhost:444/dir1/dir2",
+			pattern:     "/dir1",
+			shouldMatch: true,
+		},
+		// Test 7
+		{
+			urlStr:      "http://localhost/dir1/dir2",
+			pattern:     "*/dir2",
+			shouldMatch: false,
+		},
+	}
+
+	for i, test := range tests {
+		testPrefix := getTestPrefix(i)
+		var err error
+		context.Req.URL, err = url.Parse(test.urlStr)
+		if err != nil {
+			t.Fatalf("Failed to prepare test URL from string %s! Error was: %s", test.urlStr, err)
+		}
+
+		matches := context.PathMatches(test.pattern)
+		if matches != test.shouldMatch {
+			t.Errorf(testPrefix+"Expected and actual result differ: expected to match [%t], actual matches [%t]", test.shouldMatch, matches)
+		}
+	}
+}
+
+func TestTruncate(t *testing.T) {
+	context := getContextOrFail(t)
+	tests := []struct {
+		inputString string
+		inputLength int
+		expected    string
+	}{
+		// Test 0 - small length
+		{
+			inputString: "string",
+			inputLength: 1,
+			expected:    "s",
+		},
+		// Test 1 - exact length
+		{
+			inputString: "string",
+			inputLength: 6,
+			expected:    "string",
+		},
+		// Test 2 - bigger length
+		{
+			inputString: "string",
+			inputLength: 10,
+			expected:    "string",
+		},
+		// Test 3 - zero length
+		{
+			inputString: "string",
+			inputLength: 0,
+			expected:    "",
+		},
+		// Test 4 - negative, smaller length
+		{
+			inputString: "string",
+			inputLength: -5,
+			expected:    "tring",
+		},
+		// Test 5 - negative, exact length
+		{
+			inputString: "string",
+			inputLength: -6,
+			expected:    "string",
+		},
+		// Test 6 - negative, bigger length
+		{
+			inputString: "string",
+			inputLength: -7,
+			expected:    "string",
+		},
+	}
+
+	for i, test := range tests {
+		actual := context.Truncate(test.inputString, test.inputLength)
+		if actual != test.expected {
+			t.Errorf(getTestPrefix(i)+"Expected '%s', found '%s'. Input was Truncate(%q, %d)", test.expected, actual, test.inputString, test.inputLength)
+		}
+	}
+}
+
+func TestStripHTML(t *testing.T) {
+	context := getContextOrFail(t)
+	tests := []struct {
+		input    string
+		expected string
+	}{
+		// Test 0 - no tags
+		{
+			input:    `h1`,
+			expected: `h1`,
+		},
+		// Test 1 - happy path
+		{
+			input:    `<h1>h1</h1>`,
+			expected: `h1`,
+		},
+		// Test 2 - tag in quotes
+		{
+			input:    `<h1">">h1</h1>`,
+			expected: `h1`,
+		},
+		// Test 3 - multiple tags
+		{
+			input:    `<h1><b>h1</b></h1>`,
+			expected: `h1`,
+		},
+		// Test 4 - tags not closed
+		{
+			input:    `<h1`,
+			expected: `<h1`,
+		},
+		// Test 5 - false start
+		{
+			input:    `<h1<b>hi`,
+			expected: `<h1hi`,
+		},
+	}
+
+	for i, test := range tests {
+		actual := context.StripHTML(test.input)
+		if actual != test.expected {
+			t.Errorf(getTestPrefix(i)+"Expected %s, found %s. Input was StripHTML(%s)", test.expected, actual, test.input)
+		}
+	}
+}
+
+func TestStripExt(t *testing.T) {
+	context := getContextOrFail(t)
+	tests := []struct {
+		input    string
+		expected string
+	}{
+		// Test 0 - empty input
+		{
+			input:    "",
+			expected: "",
+		},
+		// Test 1 - relative file with ext
+		{
+			input:    "file.ext",
+			expected: "file",
+		},
+		// Test 2 - relative file without ext
+		{
+			input:    "file",
+			expected: "file",
+		},
+		// Test 3 - absolute file without ext
+		{
+			input:    "/file",
+			expected: "/file",
+		},
+		// Test 4 - absolute file with ext
+		{
+			input:    "/file.ext",
+			expected: "/file",
+		},
+		// Test 5 - with ext but ends with /
+		{
+			input:    "/dir.ext/",
+			expected: "/dir.ext/",
+		},
+		// Test 6 - file with ext under dir with ext
+		{
+			input:    "/dir.ext/file.ext",
+			expected: "/dir.ext/file",
+		},
+	}
+
+	for i, test := range tests {
+		actual := context.StripExt(test.input)
+		if actual != test.expected {
+			t.Errorf(getTestPrefix(i)+"Expected %s, found %s. Input was StripExt(%q)", test.expected, actual, test.input)
+		}
+	}
+}
+
+func initTestContext() (Context, error) {
+	body := bytes.NewBufferString("request body")
+	request, err := http.NewRequest("GET", "https://localhost", body)
+	if err != nil {
+		return Context{}, err
+	}
+
+	return Context{Root: http.Dir(os.TempDir()), Req: request}, nil
+}
+
+func getContextOrFail(t *testing.T) Context {
+	context, err := initTestContext()
+	if err != nil {
+		t.Fatalf("Failed to prepare test context")
+	}
+	return context
+}
+
+func getTestPrefix(testN int) string {
+	return fmt.Sprintf("Test [%d]: ", testN)
+}

middleware/errors/errors.go

@@ -0,0 +1,100 @@
+// Package errors implements an HTTP error handling middleware.
+package errors
+
+import (
+	"fmt"
+	"log"
+	"runtime"
+	"strings"
+	"time"
+
+	"github.com/miekg/coredns/middleware"
+	"github.com/miekg/dns"
+)
+
+// ErrorHandler handles DNS errors (and errors from other middleware).
+type ErrorHandler struct {
+	Next      middleware.Handler
+	LogFile   string
+	Log       *log.Logger
+	LogRoller *middleware.LogRoller
+	Debug     bool // if true, errors are written out to client rather than to a log
+}
+
+func (h ErrorHandler) ServeDNS(w dns.ResponseWriter, r *dns.Msg) (int, error) {
+	defer h.recovery(w, r)
+
+	rcode, err := h.Next.ServeDNS(w, r)
+
+	if err != nil {
+		errMsg := fmt.Sprintf("%s [ERROR %d %s %s] %v", time.Now().Format(timeFormat), rcode, r.Question[0].Name, dns.Type(r.Question[0].Qclass), err)
+
+		if h.Debug {
+			// Write error to response as a txt message instead of to log
+			answer := debugMsg(rcode, r)
+			txt, _ := dns.NewRR(". IN 0 TXT " + errMsg)
+			answer.Answer = append(answer.Answer, txt)
+			w.WriteMsg(answer)
+			return 0, err
+		}
+		h.Log.Println(errMsg)
+	}
+
+	return rcode, err
+}
+
+func (h ErrorHandler) recovery(w dns.ResponseWriter, r *dns.Msg) {
+	rec := recover()
+	if rec == nil {
+		return
+	}
+
+	// Obtain source of panic
+	// From: https://gist.github.com/swdunlop/9629168
+	var name, file string // function name, file name
+	var line int
+	var pc [16]uintptr
+	n := runtime.Callers(3, pc[:])
+	for _, pc := range pc[:n] {
+		fn := runtime.FuncForPC(pc)
+		if fn == nil {
+			continue
+		}
+		file, line = fn.FileLine(pc)
+		name = fn.Name()
+		if !strings.HasPrefix(name, "runtime.") {
+			break
+		}
+	}
+
+	// Trim file path
+	delim := "/coredns/"
+	pkgPathPos := strings.Index(file, delim)
+	if pkgPathPos > -1 && len(file) > pkgPathPos+len(delim) {
+		file = file[pkgPathPos+len(delim):]
+	}
+
+	panicMsg := fmt.Sprintf("%s [PANIC %s %s] %s:%d - %v", time.Now().Format(timeFormat), r.Question[0].Name, dns.Type(r.Question[0].Qtype), file, line, rec)
+	if h.Debug {
+		// Write error and stack trace to the response rather than to a log
+		var stackBuf [4096]byte
+		stack := stackBuf[:runtime.Stack(stackBuf[:], false)]
+		answer := debugMsg(dns.RcodeServerFailure, r)
+		// add stack buf in TXT, limited to 255 chars for now.
+		txt, _ := dns.NewRR(". IN 0 TXT " + string(stack[:255]))
+		answer.Answer = append(answer.Answer, txt)
+		w.WriteMsg(answer)
+	} else {
+		// Currently we don't use the function name, since file:line is more conventional
+		h.Log.Printf(panicMsg)
+	}
+}
+
+// debugMsg creates a debug message that gets send back to the client.
+func debugMsg(rcode int, r *dns.Msg) *dns.Msg {
+	answer := new(dns.Msg)
+	answer.SetRcode(r, rcode)
+	return answer
+}
+
+const timeFormat = "02/Jan/2006:15:04:05 -0700"

middleware/errors/errors_test.go

@@ -0,0 +1,168 @@
+package errors
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"log"
+	"net/http"
+	"net/http/httptest"
+	"os"
+	"path/filepath"
+	"strconv"
+	"strings"
+	"testing"
+
+	"github.com/miekg/coredns/middleware"
+)
+
+func TestErrors(t *testing.T) {
+	// create a temporary page
+	path := filepath.Join(os.TempDir(), "errors_test.html")
+	f, err := os.Create(path)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.Remove(path)
+
+	const content = "This is a error page"
+	_, err = f.WriteString(content)
+	if err != nil {
+		t.Fatal(err)
+	}
+	f.Close()
+
+	buf := bytes.Buffer{}
+	em := ErrorHandler{
+		ErrorPages: map[int]string{
+			http.StatusNotFound:  path,
+			http.StatusForbidden: "not_exist_file",
+		},
+		Log: log.New(&buf, "", 0),
+	}
+	_, notExistErr := os.Open("not_exist_file")
+
+	testErr := errors.New("test error")
+	tests := []struct {
+		next         middleware.Handler
+		expectedCode int
+		expectedBody string
+		expectedLog  string
+		expectedErr  error
+	}{
+		{
+			next:         genErrorHandler(http.StatusOK, nil, "normal"),
+			expectedCode: http.StatusOK,
+			expectedBody: "normal",
+			expectedLog:  "",
+			expectedErr:  nil,
+		},
+		{
+			next:         genErrorHandler(http.StatusMovedPermanently, testErr, ""),
+			expectedCode: http.StatusMovedPermanently,
+			expectedBody: "",
+			expectedLog:  fmt.Sprintf("[ERROR %d %s] %v\n", http.StatusMovedPermanently, "/", testErr),
+			expectedErr:  testErr,
+		},
+		{
+			next:         genErrorHandler(http.StatusBadRequest, nil, ""),
+			expectedCode: 0,
+			expectedBody: fmt.Sprintf("%d %s\n", http.StatusBadRequest,
+				http.StatusText(http.StatusBadRequest)),
+			expectedLog: "",
+			expectedErr: nil,
+		},
+		{
+			next:         genErrorHandler(http.StatusNotFound, nil, ""),
+			expectedCode: 0,
+			expectedBody: content,
+			expectedLog:  "",
+			expectedErr:  nil,
+		},
+		{
+			next:         genErrorHandler(http.StatusForbidden, nil, ""),
+			expectedCode: 0,
+			expectedBody: fmt.Sprintf("%d %s\n", http.StatusForbidden,
+				http.StatusText(http.StatusForbidden)),
+			expectedLog: fmt.Sprintf("[NOTICE %d /] could not load error page: %v\n",
+				http.StatusForbidden, notExistErr),
+			expectedErr: nil,
+		},
+	}
+
+	req, err := http.NewRequest("GET", "/", nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+	for i, test := range tests {
+		em.Next = test.next
+		buf.Reset()
+		rec := httptest.NewRecorder()
+		code, err := em.ServeHTTP(rec, req)
+
+		if err != test.expectedErr {
+			t.Errorf("Test %d: Expected error %v, but got %v",
+				i, test.expectedErr, err)
+		}
+		if code != test.expectedCode {
+			t.Errorf("Test %d: Expected status code %d, but got %d",
+				i, test.expectedCode, code)
+		}
+		if body := rec.Body.String(); body != test.expectedBody {
+			t.Errorf("Test %d: Expected body %q, but got %q",
+				i, test.expectedBody, body)
+		}
+		if log := buf.String(); !strings.Contains(log, test.expectedLog) {
+			t.Errorf("Test %d: Expected log %q, but got %q",
+				i, test.expectedLog, log)
+		}
+	}
+}
+
+func TestVisibleErrorWithPanic(t *testing.T) {
+	const panicMsg = "I'm a panic"
+	eh := ErrorHandler{
+		ErrorPages: make(map[int]string),
+		Debug:      true,
+		Next: middleware.HandlerFunc(func(w http.ResponseWriter, r *http.Request) (int, error) {
+			panic(panicMsg)
+		}),
+	}
+
+	req, err := http.NewRequest("GET", "/", nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+	rec := httptest.NewRecorder()
+
+	code, err := eh.ServeHTTP(rec, req)
+
+	if code != 0 {
+		t.Errorf("Expected error handler to return 0 (it should write to response), got status %d", code)
+	}
+	if err != nil {
+		t.Errorf("Expected error handler to return nil error (it should panic!), but got '%v'", err)
+	}
+
+	body := rec.Body.String()
+
+	if !strings.Contains(body, "[PANIC /] middleware/errors/errors_test.go") {
+		t.Errorf("Expected response body to contain error log line, but it didn't:\n%s", body)
+	}
+	if !strings.Contains(body, panicMsg) {
+		t.Errorf("Expected response body to contain panic message, but it didn't:\n%s", body)
+	}
+	if len(body) < 500 {
+		t.Errorf("Expected response body to contain stack trace, but it was too short: len=%d", len(body))
+	}
+}
+
+func genErrorHandler(status int, err error, body string) middleware.Handler {
+	return middleware.HandlerFunc(func(w http.ResponseWriter, r *http.Request) (int, error) {
+		if len(body) > 0 {
+			w.Header().Set("Content-Length", strconv.Itoa(len(body)))
+			fmt.Fprint(w, body)
+		}
+		return status, err
+	})
+}

middleware/exchange.go

@@ -0,0 +1,10 @@
+package middleware
+
+import "github.com/miekg/dns"
+
+// Exchang sends message m to the server.
+// TODO(miek): optionally it can do retries of other silly stuff.
+func Exchange(c *dns.Client, m *dns.Msg, server string) (*dns.Msg, error) {
+	r, _, err := c.Exchange(m, server)
+	return r, err
+}

middleware/file/file.go

@@ -0,0 +1,89 @@
+package file
+
+// TODO(miek): the zone's implementation is basically non-existent
+// we return a list and when searching for an answer we iterate
+// over the list. This must be moved to a tree-like structure and
+// have some fluff for DNSSEC (and be memory efficient).
+
+import (
+	"strings"
+
+	"github.com/miekg/coredns/middleware"
+	"github.com/miekg/dns"
+)
+
+type (
+	File struct {
+		Next  middleware.Handler
+		Zones Zones
+		// Maybe a list of all zones as well, as a []string?
+	}
+
+	Zone  []dns.RR
+	Zones struct {
+		Z     map[string]Zone // utterly braindead impl. TODO(miek): fix
+		Names []string
+	}
+)
+
+func (f File) ServeDNS(w dns.ResponseWriter, r *dns.Msg) (int, error) {
+	context := middleware.Context{W: w, Req: r}
+	qname := context.Name()
+	zone := middleware.Zones(f.Zones.Names).Matches(qname)
+	if zone == "" {
+		return f.Next.ServeDNS(w, r)
+	}
+
+	names, nodata := f.Zones.Z[zone].lookup(qname, context.QType())
+	var answer *dns.Msg
+	switch {
+	case nodata:
+		answer = context.AnswerMessage()
+		answer.Ns = names
+	case len(names) == 0:
+		answer = context.AnswerMessage()
+		answer.Ns = names
+		answer.Rcode = dns.RcodeNameError
+	case len(names) > 0:
+		answer = context.AnswerMessage()
+		answer.Answer = names
+	default:
+		answer = context.ErrorMessage(dns.RcodeServerFailure)
+	}
+	// Check return size, etc. TODO(miek)
+	w.WriteMsg(answer)
+	return 0, nil
+}
+
+// Lookup will try to find qname and qtype in z. It returns the
+// records found *or* a boolean saying NODATA. If the answer
+// is NODATA then the RR returned is the SOA record.
+//
+// TODO(miek): EXTREMELY STUPID IMPLEMENTATION.
+// Doesn't do much, no delegation, no cname, nothing really, etc.
+// TODO(miek): even NODATA looks broken
+func (z Zone) lookup(qname string, qtype uint16) ([]dns.RR, bool) {
+	var (
+		nodata bool
+		rep    []dns.RR
+		soa    dns.RR
+	)
+
+	for _, rr := range z {
+		if rr.Header().Rrtype == dns.TypeSOA {
+			soa = rr
+		}
+		// Match function in Go DNS?
+		if strings.ToLower(rr.Header().Name) == qname {
+			if rr.Header().Rrtype == qtype {
+				rep = append(rep, rr)
+				nodata = false
+			}
+
+		}
+	}
+	if nodata {
+		return []dns.RR{soa}, true
+	}
+	return rep, false
+}

middleware/file/file_test.go

@@ -0,0 +1,325 @@
+package file
+
+import (
+	"errors"
+	"net/http"
+	"net/http/httptest"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+)
+
+var testDir = filepath.Join(os.TempDir(), "caddy_testdir")
+var ErrCustom = errors.New("Custom Error")
+
+// testFiles is a map with relative paths to test files as keys and file content as values.
+// The map represents the following structure:
+// - $TEMP/caddy_testdir/
+// '-- file1.html
+// '-- dirwithindex/
+// '---- index.html
+// '-- dir/
+// '---- file2.html
+// '---- hidden.html
+var testFiles = map[string]string{
+	"file1.html":                                "<h1>file1.html</h1>",
+	filepath.Join("dirwithindex", "index.html"): "<h1>dirwithindex/index.html</h1>",
+	filepath.Join("dir", "file2.html"):          "<h1>dir/file2.html</h1>",
+	filepath.Join("dir", "hidden.html"):         "<h1>dir/hidden.html</h1>",
+}
+
+// TestServeHTTP covers positive scenarios when serving files.
+func TestServeHTTP(t *testing.T) {
+
+	beforeServeHTTPTest(t)
+	defer afterServeHTTPTest(t)
+
+	fileserver := FileServer(http.Dir(testDir), []string{"hidden.html"})
+
+	movedPermanently := "Moved Permanently"
+
+	tests := []struct {
+		url string
+
+		expectedStatus      int
+		expectedBodyContent string
+	}{
+		// Test 0 - access without any path
+		{
+			url:            "https://foo",
+			expectedStatus: http.StatusNotFound,
+		},
+		// Test 1 - access root (without index.html)
+		{
+			url:            "https://foo/",
+			expectedStatus: http.StatusNotFound,
+		},
+		// Test 2 - access existing file
+		{
+			url:                 "https://foo/file1.html",
+			expectedStatus:      http.StatusOK,
+			expectedBodyContent: testFiles["file1.html"],
+		},
+		// Test 3 - access folder with index file with trailing slash
+		{
+			url:                 "https://foo/dirwithindex/",
+			expectedStatus:      http.StatusOK,
+			expectedBodyContent: testFiles[filepath.Join("dirwithindex", "index.html")],
+		},
+		// Test 4 - access folder with index file without trailing slash
+		{
+			url:                 "https://foo/dirwithindex",
+			expectedStatus:      http.StatusMovedPermanently,
+			expectedBodyContent: movedPermanently,
+		},
+		// Test 5 - access folder without index file
+		{
+			url:            "https://foo/dir/",
+			expectedStatus: http.StatusNotFound,
+		},
+		// Test 6 - access folder without trailing slash
+		{
+			url:                 "https://foo/dir",
+			expectedStatus:      http.StatusMovedPermanently,
+			expectedBodyContent: movedPermanently,
+		},
+		// Test 6 - access file with trailing slash
+		{
+			url:                 "https://foo/file1.html/",
+			expectedStatus:      http.StatusMovedPermanently,
+			expectedBodyContent: movedPermanently,
+		},
+		// Test 7 - access not existing path
+		{
+			url:            "https://foo/not_existing",
+			expectedStatus: http.StatusNotFound,
+		},
+		// Test 8 - access a file, marked as hidden
+		{
+			url:            "https://foo/dir/hidden.html",
+			expectedStatus: http.StatusNotFound,
+		},
+		// Test 9 - access a index file directly
+		{
+			url:                 "https://foo/dirwithindex/index.html",
+			expectedStatus:      http.StatusOK,
+			expectedBodyContent: testFiles[filepath.Join("dirwithindex", "index.html")],
+		},
+		// Test 10 - send a request with query params
+		{
+			url:                 "https://foo/dir?param1=val",
+			expectedStatus:      http.StatusMovedPermanently,
+			expectedBodyContent: movedPermanently,
+		},
+	}
+
+	for i, test := range tests {
+		responseRecorder := httptest.NewRecorder()
+		request, err := http.NewRequest("GET", test.url, strings.NewReader(""))
+		status, err := fileserver.ServeHTTP(responseRecorder, request)
+
+		// check if error matches expectations
+		if err != nil {
+			t.Errorf(getTestPrefix(i)+"Serving file at %s failed. Error was: %v", test.url, err)
+		}
+
+		// check status code
+		if test.expectedStatus != status {
+			t.Errorf(getTestPrefix(i)+"Expected status %d, found %d", test.expectedStatus, status)
+		}
+
+		// check body content
+		if !strings.Contains(responseRecorder.Body.String(), test.expectedBodyContent) {
+			t.Errorf(getTestPrefix(i)+"Expected body to contain %q, found %q", test.expectedBodyContent, responseRecorder.Body.String())
+		}
+	}
+
+}
+
+// beforeServeHTTPTest creates a test directory with the structure, defined in the variable testFiles
+func beforeServeHTTPTest(t *testing.T) {
+	// make the root test dir
+	err := os.Mkdir(testDir, os.ModePerm)
+	if err != nil {
+		if !os.IsExist(err) {
+			t.Fatalf("Failed to create test dir. Error was: %v", err)
+			return
+		}
+	}
+
+	for relFile, fileContent := range testFiles {
+		absFile := filepath.Join(testDir, relFile)
+
+		// make sure the parent directories exist
+		parentDir := filepath.Dir(absFile)
+		_, err = os.Stat(parentDir)
+		if err != nil {
+			os.MkdirAll(parentDir, os.ModePerm)
+		}
+
+		// now create the test files
+		f, err := os.Create(absFile)
+		if err != nil {
+			t.Fatalf("Failed to create test file %s. Error was: %v", absFile, err)
+			return
+		}
+
+		// and fill them with content
+		_, err = f.WriteString(fileContent)
+		if err != nil {
+			t.Fatalf("Failed to write to %s. Error was: %v", absFile, err)
+			return
+		}
+		f.Close()
+	}
+
+}
+
+// afterServeHTTPTest removes the test dir and all its content
+func afterServeHTTPTest(t *testing.T) {
+	// cleans up everything under the test dir. No need to clean the individual files.
+	err := os.RemoveAll(testDir)
+	if err != nil {
+		t.Fatalf("Failed to clean up test dir %s. Error was: %v", testDir, err)
+	}
+}
+
+// failingFS implements the http.FileSystem interface. The Open method always returns the error, assigned to err
+type failingFS struct {
+	err      error     // the error to return when Open is called
+	fileImpl http.File // inject the file implementation
+}
+
+// Open returns the assigned failingFile and error
+func (f failingFS) Open(path string) (http.File, error) {
+	return f.fileImpl, f.err
+}
+
+// failingFile implements http.File but returns a predefined error on every Stat() method call.
+type failingFile struct {
+	http.File
+	err error
+}
+
+// Stat returns nil FileInfo and the provided error on every call
+func (ff failingFile) Stat() (os.FileInfo, error) {
+	return nil, ff.err
+}
+
+// Close is noop and returns no error
+func (ff failingFile) Close() error {
+	return nil
+}
+
+// TestServeHTTPFailingFS tests error cases where the Open function fails with various errors.
+func TestServeHTTPFailingFS(t *testing.T) {
+
+	tests := []struct {
+		fsErr           error
+		expectedStatus  int
+		expectedErr     error
+		expectedHeaders map[string]string
+	}{
+		{
+			fsErr:          os.ErrNotExist,
+			expectedStatus: http.StatusNotFound,
+			expectedErr:    nil,
+		},
+		{
+			fsErr:          os.ErrPermission,
+			expectedStatus: http.StatusForbidden,
+			expectedErr:    os.ErrPermission,
+		},
+		{
+			fsErr:           ErrCustom,
+			expectedStatus:  http.StatusServiceUnavailable,
+			expectedErr:     ErrCustom,
+			expectedHeaders: map[string]string{"Retry-After": "5"},
+		},
+	}
+
+	for i, test := range tests {
+		// initialize a file server with the failing FileSystem
+		fileserver := FileServer(failingFS{err: test.fsErr}, nil)
+
+		// prepare the request and response
+		request, err := http.NewRequest("GET", "https://foo/", nil)
+		if err != nil {
+			t.Fatalf("Failed to build request. Error was: %v", err)
+		}
+		responseRecorder := httptest.NewRecorder()
+
+		status, actualErr := fileserver.ServeHTTP(responseRecorder, request)
+
+		// check the status
+		if status != test.expectedStatus {
+			t.Errorf(getTestPrefix(i)+"Expected status %d, found %d", test.expectedStatus, status)
+		}
+
+		// check the error
+		if actualErr != test.expectedErr {
+			t.Errorf(getTestPrefix(i)+"Expected err %v, found %v", test.expectedErr, actualErr)
+		}
+
+		// check the headers - a special case for server under load
+		if test.expectedHeaders != nil && len(test.expectedHeaders) > 0 {
+			for expectedKey, expectedVal := range test.expectedHeaders {
+				actualVal := responseRecorder.Header().Get(expectedKey)
+				if expectedVal != actualVal {
+					t.Errorf(getTestPrefix(i)+"Expected header %s: %s, found %s", expectedKey, expectedVal, actualVal)
+				}
+			}
+		}
+	}
+}
+
+// TestServeHTTPFailingStat tests error cases where the initial Open function succeeds, but the Stat method on the opened file fails.
+func TestServeHTTPFailingStat(t *testing.T) {
+
+	tests := []struct {
+		statErr        error
+		expectedStatus int
+		expectedErr    error
+	}{
+		{
+			statErr:        os.ErrNotExist,
+			expectedStatus: http.StatusNotFound,
+			expectedErr:    nil,
+		},
+		{
+			statErr:        os.ErrPermission,
+			expectedStatus: http.StatusForbidden,
+			expectedErr:    os.ErrPermission,
+		},
+		{
+			statErr:        ErrCustom,
+			expectedStatus: http.StatusInternalServerError,
+			expectedErr:    ErrCustom,
+		},
+	}
+
+	for i, test := range tests {
+		// initialize a file server. The FileSystem will not fail, but calls to the Stat method of the returned File object will
+		fileserver := FileServer(failingFS{err: nil, fileImpl: failingFile{err: test.statErr}}, nil)
+
+		// prepare the request and response
+		request, err := http.NewRequest("GET", "https://foo/", nil)
+		if err != nil {
+			t.Fatalf("Failed to build request. Error was: %v", err)
+		}
+		responseRecorder := httptest.NewRecorder()
+
+		status, actualErr := fileserver.ServeHTTP(responseRecorder, request)
+
+		// check the status
+		if status != test.expectedStatus {
+			t.Errorf(getTestPrefix(i)+"Expected status %d, found %d", test.expectedStatus, status)
+		}
+
+		// check the error
+		if actualErr != test.expectedErr {
+			t.Errorf(getTestPrefix(i)+"Expected err %v, found %v", test.expectedErr, actualErr)
+		}
+	}
+}

middleware/host.go

@@ -0,0 +1,22 @@
+package middleware
+
+import (
+	"net"
+	"strings"
+
+	"github.com/miekg/dns"
+)
+
+// Host represents a host from the Caddyfile, may contain port.
+type Host string
+
+// Standard host will return the host portion of host, stripping
+// of any port. The host will also be fully qualified and lowercased.
+func (h Host) StandardHost() string {
+	// separate host and port
+	host, _, err := net.SplitHostPort(string(h))
+	if err != nil {
+		host, _, _ = net.SplitHostPort(string(h) + ":")
+	}
+	return strings.ToLower(dns.Fqdn(host))
+}

middleware/log/log.go

@@ -0,0 +1,66 @@
+// Package log implements basic but useful request (access) logging middleware.
+package log
+
+import (
+	"log"
+
+	"github.com/miekg/coredns/middleware"
+	"github.com/miekg/dns"
+)
+
+// Logger is a basic request logging middleware.
+type Logger struct {
+	Next      middleware.Handler
+	Rules     []Rule
+	ErrorFunc func(dns.ResponseWriter, *dns.Msg, int) // failover error handler
+}
+
+func (l Logger) ServeDNS(w dns.ResponseWriter, r *dns.Msg) (int, error) {
+	for _, rule := range l.Rules {
+		/*
+			if middleware.Path(r.URL.Path).Matches(rule.PathScope) {
+				responseRecorder := middleware.NewResponseRecorder(w)
+				status, err := l.Next.ServeHTTP(responseRecorder, r)
+				if status >= 400 {
+					// There was an error up the chain, but no response has been written yet.
+					// The error must be handled here so the log entry will record the response size.
+					if l.ErrorFunc != nil {
+						l.ErrorFunc(responseRecorder, r, status)
+					} else {
+						// Default failover error handler
+						responseRecorder.WriteHeader(status)
+						fmt.Fprintf(responseRecorder, "%d %s", status, http.StatusText(status))
+					}
+					status = 0
+				}
+				rep := middleware.NewReplacer(r, responseRecorder, CommonLogEmptyValue)
+				rule.Log.Println(rep.Replace(rule.Format))
+				return status, err
+			}
+		*/
+		rule = rule
+	}
+	return l.Next.ServeDNS(w, r)
+}
+
+// Rule configures the logging middleware.
+type Rule struct {
+	PathScope  string
+	OutputFile string
+	Format     string
+	Log        *log.Logger
+	Roller     *middleware.LogRoller
+}
+
+const (
+	// DefaultLogFilename is the default log filename.
+	DefaultLogFilename = "access.log"
+	// CommonLogFormat is the common log format.
+	CommonLogFormat = `{remote} ` + CommonLogEmptyValue + ` [{when}] "{type} {name} {proto}" {rcode} {size}`
+	// CommonLogEmptyValue is the common empty log value.
+	CommonLogEmptyValue = "-"
+	// CombinedLogFormat is the combined log format.
+	CombinedLogFormat = CommonLogFormat + ` "{>Referer}" "{>User-Agent}"` // Something here as well
+	// DefaultLogFormat is the default log format.
+	DefaultLogFormat = CommonLogFormat
+)

middleware/log/log_test.go

@@ -0,0 +1,48 @@
+package log
+
+import (
+	"bytes"
+	"log"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+)
+
+type erroringMiddleware struct{}
+
+func (erroringMiddleware) ServeHTTP(w http.ResponseWriter, r *http.Request) (int, error) {
+	return http.StatusNotFound, nil
+}
+
+func TestLoggedStatus(t *testing.T) {
+	var f bytes.Buffer
+	var next erroringMiddleware
+	rule := Rule{
+		PathScope: "/",
+		Format:    DefaultLogFormat,
+		Log:       log.New(&f, "", 0),
+	}
+
+	logger := Logger{
+		Rules: []Rule{rule},
+		Next:  next,
+	}
+
+	r, err := http.NewRequest("GET", "/", nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	rec := httptest.NewRecorder()
+
+	status, err := logger.ServeHTTP(rec, r)
+	if status != 0 {
+		t.Error("Expected status to be 0 - was", status)
+	}
+
+	logged := f.String()
+	if !strings.Contains(logged, "404 13") {
+		t.Error("Expected 404 to be logged. Logged string -", logged)
+	}
+}

middleware/middleware.go

@@ -0,0 +1,105 @@
+// Package middleware provides some types and functions common among middleware.
+package middleware
+
+import (
+	"time"
+
+	"github.com/miekg/dns"
+)
+
+type (
+	// Middleware is the middle layer which represents the traditional
+	// idea of middleware: it chains one Handler to the next by being
+	// passed the next Handler in the chain.
+	Middleware func(Handler) Handler
+
+	// Handler is like dns.Handler except ServeDNS may return an rcode
+	// and/or error.
+	//
+	// If ServeDNS writes to the response body, it should return a status
+	// code of 0. This signals to other handlers above it that the response
+	// body is already written, and that they should not write to it also.
+	//
+	// If ServeDNS encounters an error, it should return the error value
+	// so it can be logged by designated error-handling middleware.
+	//
+	// If writing a response after calling another ServeDNS method, the
+	// returned rcode SHOULD be used when writing the response.
+	//
+	// If handling errors after calling another ServeDNS method, the
+	// returned error value SHOULD be logged or handled accordingly.
+	//
+	// Otherwise, return values should be propagated down the middleware
+	// chain by returning them unchanged.
+	Handler interface {
+		ServeDNS(dns.ResponseWriter, *dns.Msg) (int, error)
+	}
+
+	// HandlerFunc is a convenience type like dns.HandlerFunc, except
+	// ServeDNS returns an rcode and an error. See Handler
+	// documentation for more information.
+	HandlerFunc func(dns.ResponseWriter, *dns.Msg) (int, error)
+)
+
+// ServeDNS implements the Handler interface.
+func (f HandlerFunc) ServeDNS(w dns.ResponseWriter, r *dns.Msg) (int, error) {
+	return f(w, r)
+}
+
+// IndexFile looks for a file in /root/fpath/indexFile for each string
+// in indexFiles. If an index file is found, it returns the root-relative
+// path to the file and true. If no index file is found, empty string
+// and false is returned. fpath must end in a forward slash '/'
+// otherwise no index files will be tried (directory paths must end
+// in a forward slash according to HTTP).
+//
+// All paths passed into and returned from this function use '/' as the
+// path separator, just like URLs.  IndexFle handles path manipulation
+// internally for systems that use different path separators.
+/*
+func IndexFile(root http.FileSystem, fpath string, indexFiles []string) (string, bool) {
+	if fpath[len(fpath)-1] != '/' || root == nil {
+		return "", false
+	}
+	for _, indexFile := range indexFiles {
+		// func (http.FileSystem).Open wants all paths separated by "/",
+		// regardless of operating system convention, so use
+		// path.Join instead of filepath.Join
+		fp := path.Join(fpath, indexFile)
+		f, err := root.Open(fp)
+		if err == nil {
+			f.Close()
+			return fp, true
+		}
+	}
+	return "", false
+}
+
+// SetLastModifiedHeader checks if the provided modTime is valid and if it is sets it
+// as a Last-Modified header to the ResponseWriter. If the modTime is in the future
+// the current time is used instead.
+func SetLastModifiedHeader(w http.ResponseWriter, modTime time.Time) {
+	if modTime.IsZero() || modTime.Equal(time.Unix(0, 0)) {
+		// the time does not appear to be valid. Don't put it in the response
+		return
+	}
+
+	// RFC 2616 - Section 14.29 - Last-Modified:
+	// An origin server MUST NOT send a Last-Modified date which is later than the
+	// server's time of message origination. In such cases, where the resource's last
+	// modification would indicate some time in the future, the server MUST replace
+	// that date with the message origination date.
+	now := currentTime()
+	if modTime.After(now) {
+		modTime = now
+	}
+
+	w.Header().Set("Last-Modified", modTime.UTC().Format(http.TimeFormat))
+}
+*/
+
+// currentTime, as it is defined here, returns time.Now().
+// It's defined as a variable for mocking time in tests.
+var currentTime = func() time.Time {
+	return time.Now()
+}

middleware/middleware_test.go

@@ -0,0 +1,108 @@
+package middleware
+
+import (
+	"fmt"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+	"time"
+)
+
+func TestIndexfile(t *testing.T) {
+	tests := []struct {
+		rootDir           http.FileSystem
+		fpath             string
+		indexFiles        []string
+		shouldErr         bool
+		expectedFilePath  string //retun value
+		expectedBoolValue bool   //return value
+	}{
+		{
+			http.Dir("./templates/testdata"),
+			"/images/",
+			[]string{"img.htm"},
+			false,
+			"/images/img.htm",
+			true,
+		},
+	}
+	for i, test := range tests {
+		actualFilePath, actualBoolValue := IndexFile(test.rootDir, test.fpath, test.indexFiles)
+		if actualBoolValue == true && test.shouldErr {
+			t.Errorf("Test %d didn't error, but it should have", i)
+		} else if actualBoolValue != true && !test.shouldErr {
+			t.Errorf("Test %d errored, but it shouldn't have; got %s", i, "Please Add a / at the end of fpath or the indexFiles doesnt exist")
+		}
+		if actualFilePath != test.expectedFilePath {
+			t.Fatalf("Test %d expected returned filepath to be %s, but got %s ",
+				i, test.expectedFilePath, actualFilePath)
+
+		}
+		if actualBoolValue != test.expectedBoolValue {
+			t.Fatalf("Test %d expected returned bool value to be %v, but got %v ",
+				i, test.expectedBoolValue, actualBoolValue)
+
+		}
+	}
+}
+
+func TestSetLastModified(t *testing.T) {
+	nowTime := time.Now()
+
+	// ovewrite the function to return reliable time
+	originalGetCurrentTimeFunc := currentTime
+	currentTime = func() time.Time {
+		return nowTime
+	}
+	defer func() {
+		currentTime = originalGetCurrentTimeFunc
+	}()
+
+	pastTime := nowTime.Truncate(1 * time.Hour)
+	futureTime := nowTime.Add(1 * time.Hour)
+
+	tests := []struct {
+		inputModTime         time.Time
+		expectedIsHeaderSet  bool
+		expectedLastModified string
+	}{
+		{
+			inputModTime:         pastTime,
+			expectedIsHeaderSet:  true,
+			expectedLastModified: pastTime.UTC().Format(http.TimeFormat),
+		},
+		{
+			inputModTime:         nowTime,
+			expectedIsHeaderSet:  true,
+			expectedLastModified: nowTime.UTC().Format(http.TimeFormat),
+		},
+		{
+			inputModTime:         futureTime,
+			expectedIsHeaderSet:  true,
+			expectedLastModified: nowTime.UTC().Format(http.TimeFormat),
+		},
+		{
+			inputModTime:        time.Time{},
+			expectedIsHeaderSet: false,
+		},
+	}
+
+	for i, test := range tests {
+		responseRecorder := httptest.NewRecorder()
+		errorPrefix := fmt.Sprintf("Test [%d]: ", i)
+		SetLastModifiedHeader(responseRecorder, test.inputModTime)
+		actualLastModifiedHeader := responseRecorder.Header().Get("Last-Modified")
+
+		if test.expectedIsHeaderSet && actualLastModifiedHeader == "" {
+			t.Fatalf(errorPrefix + "Expected to find Last-Modified header, but found nothing")
+		}
+
+		if !test.expectedIsHeaderSet && actualLastModifiedHeader != "" {
+			t.Fatalf(errorPrefix+"Did not expect to find Last-Modified header, but found one [%s].", actualLastModifiedHeader)
+		}
+
+		if test.expectedLastModified != actualLastModifiedHeader {
+			t.Errorf(errorPrefix+"Expected Last-Modified content [%s], found [%s}", test.expectedLastModified, actualLastModifiedHeader)
+		}
+	}
+}

middleware/path.go

@@ -0,0 +1,18 @@
+package middleware
+
+import "strings"
+
+
+// TODO(miek): matches for names.
+
+// Path represents a URI path, maybe with pattern characters.
+type Path string
+
+// Matches checks to see if other matches p.
+//
+// Path matching will probably not always be a direct
+// comparison; this method assures that paths can be
+// easily and consistently matched.
+func (p Path) Matches(other string) bool {
+	return strings.HasPrefix(string(p), other)
+}

middleware/prometheus/handler.go

@@ -0,0 +1,31 @@
+package metrics
+
+import (
+	"strconv"
+	"time"
+
+	"github.com/miekg/coredns/middleware"
+	"github.com/miekg/dns"
+)
+
+func (m *Metrics) ServeDNS(w dns.ResponseWriter, r *dns.Msg) (int, error) {
+	context := middleware.Context{W: w, Req: r}
+
+	qname := context.Name()
+	qtype := context.Type()
+	zone := middleware.Zones(m.ZoneNames).Matches(qname)
+	if zone == "" {
+		zone = "."
+	}
+
+	// Record response to get status code and size of the reply.
+	rw := middleware.NewResponseRecorder(w)
+	status, err := m.Next.ServeDNS(rw, r)
+
+	requestCount.WithLabelValues(zone, qtype).Inc()
+	requestDuration.WithLabelValues(zone).Observe(float64(time.Since(rw.Start()) / time.Second))
+	responseSize.WithLabelValues(zone).Observe(float64(rw.Size()))
+	responseRcode.WithLabelValues(zone, strconv.Itoa(rw.Rcode())).Inc()
+
+	return status, err
+}

middleware/prometheus/metrics.go

@@ -0,0 +1,80 @@
+package metrics
+
+import (
+	"fmt"
+	"net/http"
+	"sync"
+
+	"github.com/miekg/coredns/middleware"
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+const namespace = "daddy"
+
+var (
+	requestCount    *prometheus.CounterVec
+	requestDuration *prometheus.HistogramVec
+	responseSize    *prometheus.HistogramVec
+	responseRcode   *prometheus.CounterVec
+)
+
+const path = "/metrics"
+
+// Metrics holds the prometheus configuration. The metrics' path is fixed to be /metrics
+type Metrics struct {
+	Next      middleware.Handler
+	Addr      string // where to we listen
+	Once      sync.Once
+	ZoneNames []string
+}
+
+func (m *Metrics) Start() error {
+	m.Once.Do(func() {
+		define("")
+
+		prometheus.MustRegister(requestCount)
+		prometheus.MustRegister(requestDuration)
+		prometheus.MustRegister(responseSize)
+		prometheus.MustRegister(responseRcode)
+
+		http.Handle(path, prometheus.Handler())
+		go func() {
+			fmt.Errorf("%s", http.ListenAndServe(m.Addr, nil))
+		}()
+	})
+	return nil
+}
+
+func define(subsystem string) {
+	if subsystem == "" {
+		subsystem = "dns"
+	}
+	requestCount = prometheus.NewCounterVec(prometheus.CounterOpts{
+		Namespace: namespace,
+		Subsystem: subsystem,
+		Name:      "request_count_total",
+		Help:      "Counter of DNS requests made per zone and type.",
+	}, []string{"zone", "qtype"})
+
+	requestDuration = prometheus.NewHistogramVec(prometheus.HistogramOpts{
+		Namespace: namespace,
+		Subsystem: subsystem,
+		Name:      "request_duration_seconds",
+		Help:      "Histogram of the time (in seconds) each request took.",
+	}, []string{"zone"})
+
+	responseSize = prometheus.NewHistogramVec(prometheus.HistogramOpts{
+		Namespace: namespace,
+		Subsystem: subsystem,
+		Name:      "response_size_bytes",
+		Help:      "Size of the returns response in bytes.",
+		Buckets:   []float64{0, 100, 200, 300, 400, 511, 1023, 2047, 4095, 8291, 16e3, 32e3, 48e3, 64e3},
+	}, []string{"zone"})
+
+	responseRcode = prometheus.NewCounterVec(prometheus.CounterOpts{
+		Namespace: namespace,
+		Subsystem: subsystem,
+		Name:      "rcode_code_count_total",
+		Help:      "Counter of response status codes.",
+	}, []string{"zone", "rcode"})
+}

middleware/proxy/policy.go

@@ -0,0 +1,101 @@
+package proxy
+
+import (
+	"math/rand"
+	"sync/atomic"
+)
+
+// HostPool is a collection of UpstreamHosts.
+type HostPool []*UpstreamHost
+
+// Policy decides how a host will be selected from a pool.
+type Policy interface {
+	Select(pool HostPool) *UpstreamHost
+}
+
+func init() {
+	RegisterPolicy("random", func() Policy { return &Random{} })
+	RegisterPolicy("least_conn", func() Policy { return &LeastConn{} })
+	RegisterPolicy("round_robin", func() Policy { return &RoundRobin{} })
+}
+
+// Random is a policy that selects up hosts from a pool at random.
+type Random struct{}
+
+// Select selects an up host at random from the specified pool.
+func (r *Random) Select(pool HostPool) *UpstreamHost {
+	// instead of just generating a random index
+	// this is done to prevent selecting a down host
+	var randHost *UpstreamHost
+	count := 0
+	for _, host := range pool {
+		if host.Down() {
+			continue
+		}
+		count++
+		if count == 1 {
+			randHost = host
+		} else {
+			r := rand.Int() % count
+			if r == (count - 1) {
+				randHost = host
+			}
+		}
+	}
+	return randHost
+}
+
+// LeastConn is a policy that selects the host with the least connections.
+type LeastConn struct{}
+
+// Select selects the up host with the least number of connections in the
+// pool.  If more than one host has the same least number of connections,
+// one of the hosts is chosen at random.
+func (r *LeastConn) Select(pool HostPool) *UpstreamHost {
+	var bestHost *UpstreamHost
+	count := 0
+	leastConn := int64(1<<63 - 1)
+	for _, host := range pool {
+		if host.Down() {
+			continue
+		}
+		hostConns := host.Conns
+		if hostConns < leastConn {
+			bestHost = host
+			leastConn = hostConns
+			count = 1
+		} else if hostConns == leastConn {
+			// randomly select host among hosts with least connections
+			count++
+			if count == 1 {
+				bestHost = host
+			} else {
+				r := rand.Int() % count
+				if r == (count - 1) {
+					bestHost = host
+				}
+			}
+		}
+	}
+	return bestHost
+}
+
+// RoundRobin is a policy that selects hosts based on round robin ordering.
+type RoundRobin struct {
+	Robin uint32
+}
+
+// Select selects an up host from the pool using a round robin ordering scheme.
+func (r *RoundRobin) Select(pool HostPool) *UpstreamHost {
+	poolLen := uint32(len(pool))
+	selection := atomic.AddUint32(&r.Robin, 1) % poolLen
+	host := pool[selection]
+	// if the currently selected host is down, just ffwd to up host
+	for i := uint32(1); host.Down() && i < poolLen; i++ {
+		host = pool[(selection+i)%poolLen]
+	}
+	if host.Down() {
+		return nil
+	}
+	return host
+}

middleware/proxy/policy_test.go

@@ -0,0 +1,87 @@
+package proxy
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"os"
+	"testing"
+)
+
+var workableServer *httptest.Server
+
+func TestMain(m *testing.M) {
+	workableServer = httptest.NewServer(http.HandlerFunc(
+		func(w http.ResponseWriter, r *http.Request) {
+			// do nothing
+		}))
+	r := m.Run()
+	workableServer.Close()
+	os.Exit(r)
+}
+
+type customPolicy struct{}
+
+func (r *customPolicy) Select(pool HostPool) *UpstreamHost {
+	return pool[0]
+}
+
+func testPool() HostPool {
+	pool := []*UpstreamHost{
+		{
+			Name: workableServer.URL, // this should resolve (healthcheck test)
+		},
+		{
+			Name: "http://shouldnot.resolve", // this shouldn't
+		},
+		{
+			Name: "http://C",
+		},
+	}
+	return HostPool(pool)
+}
+
+func TestRoundRobinPolicy(t *testing.T) {
+	pool := testPool()
+	rrPolicy := &RoundRobin{}
+	h := rrPolicy.Select(pool)
+	// First selected host is 1, because counter starts at 0
+	// and increments before host is selected
+	if h != pool[1] {
+		t.Error("Expected first round robin host to be second host in the pool.")
+	}
+	h = rrPolicy.Select(pool)
+	if h != pool[2] {
+		t.Error("Expected second round robin host to be third host in the pool.")
+	}
+	// mark host as down
+	pool[0].Unhealthy = true
+	h = rrPolicy.Select(pool)
+	if h != pool[1] {
+		t.Error("Expected third round robin host to be first host in the pool.")
+	}
+}
+
+func TestLeastConnPolicy(t *testing.T) {
+	pool := testPool()
+	lcPolicy := &LeastConn{}
+	pool[0].Conns = 10
+	pool[1].Conns = 10
+	h := lcPolicy.Select(pool)
+	if h != pool[2] {
+		t.Error("Expected least connection host to be third host.")
+	}
+	pool[2].Conns = 100
+	h = lcPolicy.Select(pool)
+	if h != pool[0] && h != pool[1] {
+		t.Error("Expected least connection host to be first or second host.")
+	}
+}
+
+func TestCustomPolicy(t *testing.T) {
+	pool := testPool()
+	customPolicy := &customPolicy{}
+	h := customPolicy.Select(pool)
+	if h != pool[0] {
+		t.Error("Expected custom policy host to be the first host.")
+	}
+}

middleware/proxy/proxy.go

@@ -0,0 +1,120 @@
+// Package proxy is middleware that proxies requests.
+package proxy
+
+import (
+	"errors"
+	"net/http"
+	"sync/atomic"
+	"time"
+
+	"github.com/miekg/coredns/middleware"
+	"github.com/miekg/dns"
+)
+
+var errUnreachable = errors.New("unreachable backend")
+
+// Proxy represents a middleware instance that can proxy requests.
+type Proxy struct {
+	Next      middleware.Handler
+	Client    Client
+	Upstreams []Upstream
+}
+
+type Client struct {
+	UDP *dns.Client
+	TCP *dns.Client
+}
+
+// Upstream manages a pool of proxy upstream hosts. Select should return a
+// suitable upstream host, or nil if no such hosts are available.
+type Upstream interface {
+	// The domain name this upstream host should be routed on.
+	From() string
+	// Selects an upstream host to be routed to.
+	Select() *UpstreamHost
+	// Checks if subpdomain is not an ignored.
+	IsAllowedPath(string) bool
+}
+
+// UpstreamHostDownFunc can be used to customize how Down behaves.
+type UpstreamHostDownFunc func(*UpstreamHost) bool
+
+// UpstreamHost represents a single proxy upstream
+type UpstreamHost struct {
+	Conns             int64  // must be first field to be 64-bit aligned on 32-bit systems
+	Name              string // IP address (and port) of this upstream host
+	Fails             int32
+	FailTimeout       time.Duration
+	Unhealthy         bool
+	ExtraHeaders      http.Header
+	CheckDown         UpstreamHostDownFunc
+	WithoutPathPrefix string
+}
+
+// Down checks whether the upstream host is down or not.
+// Down will try to use uh.CheckDown first, and will fall
+// back to some default criteria if necessary.
+func (uh *UpstreamHost) Down() bool {
+	if uh.CheckDown == nil {
+		// Default settings
+		return uh.Unhealthy || uh.Fails > 0
+	}
+	return uh.CheckDown(uh)
+}
+
+// tryDuration is how long to try upstream hosts; failures result in
+// immediate retries until this duration ends or we get a nil host.
+var tryDuration = 60 * time.Second
+
+// ServeDNS satisfies the middleware.Handler interface.
+func (p Proxy) ServeDNS(w dns.ResponseWriter, r *dns.Msg) (int, error) {
+	for _, upstream := range p.Upstreams {
+		// allowed bla bla bla TODO(miek): fix full proxy spec from caddy
+		start := time.Now()
+
+		// Since Select() should give us "up" hosts, keep retrying
+		// hosts until timeout (or until we get a nil host).
+		for time.Now().Sub(start) < tryDuration {
+			host := upstream.Select()
+			if host == nil {
+				return dns.RcodeServerFailure, errUnreachable
+			}
+			// TODO(miek): PORT!
+			reverseproxy := ReverseProxy{Host: host.Name, Client: p.Client}
+
+			atomic.AddInt64(&host.Conns, 1)
+			backendErr := reverseproxy.ServeDNS(w, r, nil)
+			atomic.AddInt64(&host.Conns, -1)
+			if backendErr == nil {
+				return 0, nil
+			}
+			timeout := host.FailTimeout
+			if timeout == 0 {
+				timeout = 10 * time.Second
+			}
+			atomic.AddInt32(&host.Fails, 1)
+			go func(host *UpstreamHost, timeout time.Duration) {
+				time.Sleep(timeout)
+				atomic.AddInt32(&host.Fails, -1)
+			}(host, timeout)
+		}
+		return dns.RcodeServerFailure, errUnreachable
+	}
+	return p.Next.ServeDNS(w, r)
+}
+
+func Clients() Client {
+	udp := newClient("udp", defaultTimeout)
+	tcp := newClient("tcp", defaultTimeout)
+	return Client{UDP: udp, TCP: tcp}
+}
+
+// newClient returns a new client for proxy requests.
+func newClient(net string, timeout time.Duration) *dns.Client {
+	if timeout == 0 {
+		timeout = defaultTimeout
+	}
+	return &dns.Client{Net: net, ReadTimeout: timeout, WriteTimeout: timeout, SingleInflight: true}
+}
+
+const defaultTimeout = 5 * time.Second

middleware/proxy/proxy_test.go

@@ -0,0 +1,317 @@
+package proxy
+
+import (
+	"bufio"
+	"bytes"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"log"
+	"net"
+	"net/http"
+	"net/http/httptest"
+	"net/url"
+	"os"
+	"path/filepath"
+	"runtime"
+	"strings"
+	"testing"
+	"time"
+
+	"golang.org/x/net/websocket"
+)
+
+func init() {
+	tryDuration = 50 * time.Millisecond // prevent tests from hanging
+}
+
+func TestReverseProxy(t *testing.T) {
+	log.SetOutput(ioutil.Discard)
+	defer log.SetOutput(os.Stderr)
+
+	var requestReceived bool
+	backend := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		requestReceived = true
+		w.Write([]byte("Hello, client"))
+	}))
+	defer backend.Close()
+
+	// set up proxy
+	p := &Proxy{
+		Upstreams: []Upstream{newFakeUpstream(backend.URL, false)},
+	}
+
+	// create request and response recorder
+	r, err := http.NewRequest("GET", "/", nil)
+	if err != nil {
+		t.Fatalf("Failed to create request: %v", err)
+	}
+	w := httptest.NewRecorder()
+
+	p.ServeHTTP(w, r)
+
+	if !requestReceived {
+		t.Error("Expected backend to receive request, but it didn't")
+	}
+}
+
+func TestReverseProxyInsecureSkipVerify(t *testing.T) {
+	log.SetOutput(ioutil.Discard)
+	defer log.SetOutput(os.Stderr)
+
+	var requestReceived bool
+	backend := httptest.NewTLSServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		requestReceived = true
+		w.Write([]byte("Hello, client"))
+	}))
+	defer backend.Close()
+
+	// set up proxy
+	p := &Proxy{
+		Upstreams: []Upstream{newFakeUpstream(backend.URL, true)},
+	}
+
+	// create request and response recorder
+	r, err := http.NewRequest("GET", "/", nil)
+	if err != nil {
+		t.Fatalf("Failed to create request: %v", err)
+	}
+	w := httptest.NewRecorder()
+
+	p.ServeHTTP(w, r)
+
+	if !requestReceived {
+		t.Error("Even with insecure HTTPS, expected backend to receive request, but it didn't")
+	}
+}
+
+func TestWebSocketReverseProxyServeHTTPHandler(t *testing.T) {
+	// No-op websocket backend simply allows the WS connection to be
+	// accepted then it will be immediately closed. Perfect for testing.
+	wsNop := httptest.NewServer(websocket.Handler(func(ws *websocket.Conn) {}))
+	defer wsNop.Close()
+
+	// Get proxy to use for the test
+	p := newWebSocketTestProxy(wsNop.URL)
+
+	// Create client request
+	r, err := http.NewRequest("GET", "/", nil)
+	if err != nil {
+		t.Fatalf("Failed to create request: %v", err)
+	}
+	r.Header = http.Header{
+		"Connection":            {"Upgrade"},
+		"Upgrade":               {"websocket"},
+		"Origin":                {wsNop.URL},
+		"Sec-WebSocket-Key":     {"x3JJHMbDL1EzLkh9GBhXDw=="},
+		"Sec-WebSocket-Version": {"13"},
+	}
+
+	// Capture the request
+	w := &recorderHijacker{httptest.NewRecorder(), new(fakeConn)}
+
+	// Booya! Do the test.
+	p.ServeHTTP(w, r)
+
+	// Make sure the backend accepted the WS connection.
+	// Mostly interested in the Upgrade and Connection response headers
+	// and the 101 status code.
+	expected := []byte("HTTP/1.1 101 Switching Protocols\r\nUpgrade: websocket\r\nConnection: Upgrade\r\nSec-WebSocket-Accept: HSmrc0sMlYUkAGmm5OPpG2HaGWk=\r\n\r\n")
+	actual := w.fakeConn.writeBuf.Bytes()
+	if !bytes.Equal(actual, expected) {
+		t.Errorf("Expected backend to accept response:\n'%s'\nActually got:\n'%s'", expected, actual)
+	}
+}
+
+func TestWebSocketReverseProxyFromWSClient(t *testing.T) {
+	// Echo server allows us to test that socket bytes are properly
+	// being proxied.
+	wsEcho := httptest.NewServer(websocket.Handler(func(ws *websocket.Conn) {
+		io.Copy(ws, ws)
+	}))
+	defer wsEcho.Close()
+
+	// Get proxy to use for the test
+	p := newWebSocketTestProxy(wsEcho.URL)
+
+	// This is a full end-end test, so the proxy handler
+	// has to be part of a server listening on a port. Our
+	// WS client will connect to this test server, not
+	// the echo client directly.
+	echoProxy := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		p.ServeHTTP(w, r)
+	}))
+	defer echoProxy.Close()
+
+	// Set up WebSocket client
+	url := strings.Replace(echoProxy.URL, "http://", "ws://", 1)
+	ws, err := websocket.Dial(url, "", echoProxy.URL)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer ws.Close()
+
+	// Send test message
+	trialMsg := "Is it working?"
+	websocket.Message.Send(ws, trialMsg)
+
+	// It should be echoed back to us
+	var actualMsg string
+	websocket.Message.Receive(ws, &actualMsg)
+	if actualMsg != trialMsg {
+		t.Errorf("Expected '%s' but got '%s' instead", trialMsg, actualMsg)
+	}
+}
+
+func TestUnixSocketProxy(t *testing.T) {
+	if runtime.GOOS == "windows" {
+		return
+	}
+
+	trialMsg := "Is it working?"
+
+	var proxySuccess bool
+
+	// This is our fake "application" we want to proxy to
+	ts := httptest.NewUnstartedServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		// Request was proxied when this is called
+		proxySuccess = true
+
+		fmt.Fprint(w, trialMsg)
+	}))
+
+	// Get absolute path for unix: socket
+	socketPath, err := filepath.Abs("./test_socket")
+	if err != nil {
+		t.Fatalf("Unable to get absolute path: %v", err)
+	}
+
+	// Change httptest.Server listener to listen to unix: socket
+	ln, err := net.Listen("unix", socketPath)
+	if err != nil {
+		t.Fatalf("Unable to listen: %v", err)
+	}
+	ts.Listener = ln
+
+	ts.Start()
+	defer ts.Close()
+
+	url := strings.Replace(ts.URL, "http://", "unix:", 1)
+	p := newWebSocketTestProxy(url)
+
+	echoProxy := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		p.ServeHTTP(w, r)
+	}))
+	defer echoProxy.Close()
+
+	res, err := http.Get(echoProxy.URL)
+	if err != nil {
+		t.Fatalf("Unable to GET: %v", err)
+	}
+
+	greeting, err := ioutil.ReadAll(res.Body)
+	res.Body.Close()
+	if err != nil {
+		t.Fatalf("Unable to GET: %v", err)
+	}
+
+	actualMsg := fmt.Sprintf("%s", greeting)
+
+	if !proxySuccess {
+		t.Errorf("Expected request to be proxied, but it wasn't")
+	}
+
+	if actualMsg != trialMsg {
+		t.Errorf("Expected '%s' but got '%s' instead", trialMsg, actualMsg)
+	}
+}
+
+func newFakeUpstream(name string, insecure bool) *fakeUpstream {
+	uri, _ := url.Parse(name)
+	u := &fakeUpstream{
+		name: name,
+		host: &UpstreamHost{
+			Name:         name,
+			ReverseProxy: NewSingleHostReverseProxy(uri, ""),
+		},
+	}
+	if insecure {
+		u.host.ReverseProxy.Transport = InsecureTransport
+	}
+	return u
+}
+
+type fakeUpstream struct {
+	name string
+	host *UpstreamHost
+}
+
+func (u *fakeUpstream) From() string {
+	return "/"
+}
+
+func (u *fakeUpstream) Select() *UpstreamHost {
+	return u.host
+}
+
+func (u *fakeUpstream) IsAllowedPath(requestPath string) bool {
+	return true
+}
+
+// newWebSocketTestProxy returns a test proxy that will
+// redirect to the specified backendAddr. The function
+// also sets up the rules/environment for testing WebSocket
+// proxy.
+func newWebSocketTestProxy(backendAddr string) *Proxy {
+	return &Proxy{
+		Upstreams: []Upstream{&fakeWsUpstream{name: backendAddr}},
+	}
+}
+
+type fakeWsUpstream struct {
+	name string
+}
+
+func (u *fakeWsUpstream) From() string {
+	return "/"
+}
+
+func (u *fakeWsUpstream) Select() *UpstreamHost {
+	uri, _ := url.Parse(u.name)
+	return &UpstreamHost{
+		Name:         u.name,
+		ReverseProxy: NewSingleHostReverseProxy(uri, ""),
+		ExtraHeaders: http.Header{
+			"Connection": {"{>Connection}"},
+			"Upgrade":    {"{>Upgrade}"}},
+	}
+}
+
+func (u *fakeWsUpstream) IsAllowedPath(requestPath string) bool {
+	return true
+}
+
+// recorderHijacker is a ResponseRecorder that can
+// be hijacked.
+type recorderHijacker struct {
+	*httptest.ResponseRecorder
+	fakeConn *fakeConn
+}
+
+func (rh *recorderHijacker) Hijack() (net.Conn, *bufio.ReadWriter, error) {
+	return rh.fakeConn, nil, nil
+}
+
+type fakeConn struct {
+	readBuf  bytes.Buffer
+	writeBuf bytes.Buffer
+}
+
+func (c *fakeConn) LocalAddr() net.Addr                { return nil }
+func (c *fakeConn) RemoteAddr() net.Addr               { return nil }
+func (c *fakeConn) SetDeadline(t time.Time) error      { return nil }
+func (c *fakeConn) SetReadDeadline(t time.Time) error  { return nil }
+func (c *fakeConn) SetWriteDeadline(t time.Time) error { return nil }
+func (c *fakeConn) Close() error                       { return nil }
+func (c *fakeConn) Read(b []byte) (int, error)         { return c.readBuf.Read(b) }
+func (c *fakeConn) Write(b []byte) (int, error)        { return c.writeBuf.Write(b) }

middleware/proxy/reverseproxy.go

@@ -0,0 +1,36 @@
+// Package proxy is middleware that proxies requests.
+package proxy
+
+import (
+	"github.com/miekg/coredns/middleware"
+	"github.com/miekg/dns"
+)
+
+type ReverseProxy struct {
+	Host   string
+	Client Client
+}
+
+func (p ReverseProxy) ServeDNS(w dns.ResponseWriter, r *dns.Msg, extra []dns.RR) error {
+	// TODO(miek): use extra!
+	var (
+		reply *dns.Msg
+		err   error
+	)
+	context := middleware.Context{W: w, Req: r}
+
+	// tls+tcp ?
+	if context.Proto() == "tcp" {
+		reply, err = middleware.Exchange(p.Client.TCP, r, p.Host)
+	} else {
+		reply, err = middleware.Exchange(p.Client.UDP, r, p.Host)
+	}
+
+	if err != nil {
+		return err
+	}
+	reply.Compress = true
+	reply.Id = r.Id
+	w.WriteMsg(reply)
+	return nil
+}

middleware/proxy/upstream.go

@@ -0,0 +1,235 @@
+package proxy
+
+import (
+	"io"
+	"io/ioutil"
+	"net/http"
+	"path"
+	"strconv"
+	"time"
+
+	"github.com/miekg/coredns/core/parse"
+	"github.com/miekg/coredns/middleware"
+)
+
+var (
+	supportedPolicies = make(map[string]func() Policy)
+)
+
+type staticUpstream struct {
+	from string
+	// TODO(miek): allows use to added headers
+	proxyHeaders http.Header // TODO(miek): kill
+	Hosts        HostPool
+	Policy       Policy
+
+	FailTimeout time.Duration
+	MaxFails    int32
+	HealthCheck struct {
+		Path     string
+		Interval time.Duration
+	}
+	WithoutPathPrefix string
+	IgnoredSubPaths   []string
+}
+
+// NewStaticUpstreams parses the configuration input and sets up
+// static upstreams for the proxy middleware.
+func NewStaticUpstreams(c parse.Dispenser) ([]Upstream, error) {
+	var upstreams []Upstream
+	for c.Next() {
+		upstream := &staticUpstream{
+			from:         "",
+			proxyHeaders: make(http.Header),
+			Hosts:        nil,
+			Policy:       &Random{},
+			FailTimeout:  10 * time.Second,
+			MaxFails:     1,
+		}
+
+		if !c.Args(&upstream.from) {
+			return upstreams, c.ArgErr()
+		}
+		to := c.RemainingArgs()
+		if len(to) == 0 {
+			return upstreams, c.ArgErr()
+		}
+
+		for c.NextBlock() {
+			if err := parseBlock(&c, upstream); err != nil {
+				return upstreams, err
+			}
+		}
+
+		upstream.Hosts = make([]*UpstreamHost, len(to))
+		for i, host := range to {
+			uh := &UpstreamHost{
+				Name:         host,
+				Conns:        0,
+				Fails:        0,
+				FailTimeout:  upstream.FailTimeout,
+				Unhealthy:    false,
+				ExtraHeaders: upstream.proxyHeaders,
+				CheckDown: func(upstream *staticUpstream) UpstreamHostDownFunc {
+					return func(uh *UpstreamHost) bool {
+						if uh.Unhealthy {
+							return true
+						}
+						if uh.Fails >= upstream.MaxFails &&
+							upstream.MaxFails != 0 {
+							return true
+						}
+						return false
+					}
+				}(upstream),
+				WithoutPathPrefix: upstream.WithoutPathPrefix,
+			}
+			upstream.Hosts[i] = uh
+		}
+
+		if upstream.HealthCheck.Path != "" {
+			go upstream.HealthCheckWorker(nil)
+		}
+		upstreams = append(upstreams, upstream)
+	}
+	return upstreams, nil
+}
+
+// RegisterPolicy adds a custom policy to the proxy.
+func RegisterPolicy(name string, policy func() Policy) {
+	supportedPolicies[name] = policy
+}
+
+func (u *staticUpstream) From() string {
+	return u.from
+}
+
+func parseBlock(c *parse.Dispenser, u *staticUpstream) error {
+	switch c.Val() {
+	case "policy":
+		if !c.NextArg() {
+			return c.ArgErr()
+		}
+		policyCreateFunc, ok := supportedPolicies[c.Val()]
+		if !ok {
+			return c.ArgErr()
+		}
+		u.Policy = policyCreateFunc()
+	case "fail_timeout":
+		if !c.NextArg() {
+			return c.ArgErr()
+		}
+		dur, err := time.ParseDuration(c.Val())
+		if err != nil {
+			return err
+		}
+		u.FailTimeout = dur
+	case "max_fails":
+		if !c.NextArg() {
+			return c.ArgErr()
+		}
+		n, err := strconv.Atoi(c.Val())
+		if err != nil {
+			return err
+		}
+		u.MaxFails = int32(n)
+	case "health_check":
+		if !c.NextArg() {
+			return c.ArgErr()
+		}
+		u.HealthCheck.Path = c.Val()
+		u.HealthCheck.Interval = 30 * time.Second
+		if c.NextArg() {
+			dur, err := time.ParseDuration(c.Val())
+			if err != nil {
+				return err
+			}
+			u.HealthCheck.Interval = dur
+		}
+	case "proxy_header":
+		var header, value string
+		if !c.Args(&header, &value) {
+			return c.ArgErr()
+		}
+		u.proxyHeaders.Add(header, value)
+	case "websocket":
+		u.proxyHeaders.Add("Connection", "{>Connection}")
+		u.proxyHeaders.Add("Upgrade", "{>Upgrade}")
+	case "without":
+		if !c.NextArg() {
+			return c.ArgErr()
+		}
+		u.WithoutPathPrefix = c.Val()
+	case "except":
+		ignoredPaths := c.RemainingArgs()
+		if len(ignoredPaths) == 0 {
+			return c.ArgErr()
+		}
+		u.IgnoredSubPaths = ignoredPaths
+	default:
+		return c.Errf("unknown property '%s'", c.Val())
+	}
+	return nil
+}
+
+func (u *staticUpstream) healthCheck() {
+	for _, host := range u.Hosts {
+		hostURL := host.Name + u.HealthCheck.Path
+		if r, err := http.Get(hostURL); err == nil {
+			io.Copy(ioutil.Discard, r.Body)
+			r.Body.Close()
+			host.Unhealthy = r.StatusCode < 200 || r.StatusCode >= 400
+		} else {
+			host.Unhealthy = true
+		}
+	}
+}
+
+func (u *staticUpstream) HealthCheckWorker(stop chan struct{}) {
+	ticker := time.NewTicker(u.HealthCheck.Interval)
+	u.healthCheck()
+	for {
+		select {
+		case <-ticker.C:
+			u.healthCheck()
+		case <-stop:
+			// TODO: the library should provide a stop channel and global
+			// waitgroup to allow goroutines started by plugins a chance
+			// to clean themselves up.
+		}
+	}
+}
+
+func (u *staticUpstream) Select() *UpstreamHost {
+	pool := u.Hosts
+	if len(pool) == 1 {
+		if pool[0].Down() {
+			return nil
+		}
+		return pool[0]
+	}
+	allDown := true
+	for _, host := range pool {
+		if !host.Down() {
+			allDown = false
+			break
+		}
+	}
+	if allDown {
+		return nil
+	}
+
+	if u.Policy == nil {
+		return (&Random{}).Select(pool)
+	}
+	return u.Policy.Select(pool)
+}
+
+func (u *staticUpstream) IsAllowedPath(requestPath string) bool {
+	for _, ignoredSubPath := range u.IgnoredSubPaths {
+		if middleware.Path(path.Clean(requestPath)).Matches(path.Join(u.From(), ignoredSubPath)) {
+			return false
+		}
+	}
+	return true
+}

middleware/proxy/upstream_test.go

@@ -0,0 +1,83 @@
+package proxy
+
+import (
+	"testing"
+	"time"
+)
+
+func TestHealthCheck(t *testing.T) {
+	upstream := &staticUpstream{
+		from:        "",
+		Hosts:       testPool(),
+		Policy:      &Random{},
+		FailTimeout: 10 * time.Second,
+		MaxFails:    1,
+	}
+	upstream.healthCheck()
+	if upstream.Hosts[0].Down() {
+		t.Error("Expected first host in testpool to not fail healthcheck.")
+	}
+	if !upstream.Hosts[1].Down() {
+		t.Error("Expected second host in testpool to fail healthcheck.")
+	}
+}
+
+func TestSelect(t *testing.T) {
+	upstream := &staticUpstream{
+		from:        "",
+		Hosts:       testPool()[:3],
+		Policy:      &Random{},
+		FailTimeout: 10 * time.Second,
+		MaxFails:    1,
+	}
+	upstream.Hosts[0].Unhealthy = true
+	upstream.Hosts[1].Unhealthy = true
+	upstream.Hosts[2].Unhealthy = true
+	if h := upstream.Select(); h != nil {
+		t.Error("Expected select to return nil as all host are down")
+	}
+	upstream.Hosts[2].Unhealthy = false
+	if h := upstream.Select(); h == nil {
+		t.Error("Expected select to not return nil")
+	}
+}
+
+func TestRegisterPolicy(t *testing.T) {
+	name := "custom"
+	customPolicy := &customPolicy{}
+	RegisterPolicy(name, func() Policy { return customPolicy })
+	if _, ok := supportedPolicies[name]; !ok {
+		t.Error("Expected supportedPolicies to have a custom policy.")
+	}
+
+}
+
+func TestAllowedPaths(t *testing.T) {
+	upstream := &staticUpstream{
+		from:            "/proxy",
+		IgnoredSubPaths: []string{"/download", "/static"},
+	}
+	tests := []struct {
+		url      string
+		expected bool
+	}{
+		{"/proxy", true},
+		{"/proxy/dl", true},
+		{"/proxy/download", false},
+		{"/proxy/download/static", false},
+		{"/proxy/static", false},
+		{"/proxy/static/download", false},
+		{"/proxy/something/download", true},
+		{"/proxy/something/static", true},
+		{"/proxy//static", false},
+		{"/proxy//static//download", false},
+		{"/proxy//download", false},
+	}
+
+	for i, test := range tests {
+		isAllowed := upstream.IsAllowedPath(test.url)
+		if test.expected != isAllowed {
+			t.Errorf("Test %d: expected %v found %v", i+1, test.expected, isAllowed)
+		}
+	}
+}

middleware/recorder.go

@@ -0,0 +1,70 @@
+package middleware
+
+import (
+	"time"
+
+	"github.com/miekg/dns"
+)
+
+// ResponseRecorder is a type of ResponseWriter that captures
+// the rcode code written to it and also the size of the message
+// written in the response. A rcode code does not have
+// to be written, however, in which case 0 must be assumed.
+// It is best to have the constructor initialize this type
+// with that default status code.
+type ResponseRecorder struct {
+	dns.ResponseWriter
+	rcode int
+	size  int
+	start time.Time
+}
+
+// NewResponseRecorder makes and returns a new responseRecorder,
+// which captures the DNS rcode from the ResponseWriter
+// and also the length of the response message written through it.
+func NewResponseRecorder(w dns.ResponseWriter) *ResponseRecorder {
+	return &ResponseRecorder{
+		ResponseWriter: w,
+		rcode:          0,
+		start:          time.Now(),
+	}
+}
+
+// WriteMsg records the status code and calls the
+// underlying ResponseWriter's WriteMsg method.
+func (r *ResponseRecorder) WriteMsg(res *dns.Msg) error {
+	r.rcode = res.Rcode
+	r.size = res.Len()
+	return r.ResponseWriter.WriteMsg(res)
+}
+
+// Write is a wrapper that records the size of the message that gets written.
+func (r *ResponseRecorder) Write(buf []byte) (int, error) {
+	n, err := r.ResponseWriter.Write(buf)
+	if err == nil {
+		r.size += n
+	}
+	return n, err
+}
+
+// Size returns the size.
+func (r *ResponseRecorder) Size() int {
+	return r.size
+}
+
+// Rcode returns the rcode.
+func (r *ResponseRecorder) Rcode() int {
+	return r.rcode
+}
+
+// Start returns the start time of the ResponseRecorder.
+func (r *ResponseRecorder) Start() time.Time {
+	return r.start
+}
+
+// Hijack implements dns.Hijacker. It simply wraps the underlying
+// ResponseWriter's Hijack method if there is one, or returns an error.
+func (r *ResponseRecorder) Hijack() {
+	r.ResponseWriter.Hijack()
+	return
+}

middleware/recorder_test.go

@@ -0,0 +1,32 @@
+package middleware
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+)
+
+func TestNewResponseRecorder(t *testing.T) {
+	w := httptest.NewRecorder()
+	recordRequest := NewResponseRecorder(w)
+	if !(recordRequest.ResponseWriter == w) {
+		t.Fatalf("Expected Response writer in the Recording to be same as the one sent\n")
+	}
+	if recordRequest.status != http.StatusOK {
+		t.Fatalf("Expected recorded status  to be http.StatusOK (%d) , but found %d\n ", http.StatusOK, recordRequest.status)
+	}
+}
+
+func TestWrite(t *testing.T) {
+	w := httptest.NewRecorder()
+	responseTestString := "test"
+	recordRequest := NewResponseRecorder(w)
+	buf := []byte(responseTestString)
+	recordRequest.Write(buf)
+	if recordRequest.size != len(buf) {
+		t.Fatalf("Expected the bytes written counter to be %d, but instead found %d\n", len(buf), recordRequest.size)
+	}
+	if w.Body.String() != responseTestString {
+		t.Fatalf("Expected Response Body to be %s , but found %s\n", responseTestString, w.Body.String())
+	}
+}

middleware/reflect/reflect.go

@@ -0,0 +1,84 @@
+// Reflect provides middleware that reflects back some client properties.
+// This is the default middleware when Caddy is run without configuration.
+//
+// The left-most label must be `who`.
+// When queried for type A (resp. AAAA), it sends back the IPv4 (resp. v6) address.
+// In the additional section the port number and transport are shown.
+// Basic use pattern:
+//
+//	dig @localhost -p 1053 who.miek.nl A
+//
+//	;; ANSWER SECTION:
+//	who.miek.nl.		0	IN	A	127.0.0.1
+//
+//	;; ADDITIONAL SECTION:
+//	who.miek.nl.		0	IN	TXT	"Port: 56195 (udp)"
+package reflect
+
+import (
+	"errors"
+	"net"
+	"strings"
+
+	"github.com/miekg/coredns/middleware"
+	"github.com/miekg/dns"
+)
+
+type Reflect struct {
+	Next middleware.Handler
+}
+
+func (rl Reflect) ServeDNS(w dns.ResponseWriter, r *dns.Msg) (int, error) {
+	context := middleware.Context{Req: r, W: w}
+
+	class := r.Question[0].Qclass
+	qname := r.Question[0].Name
+	i, ok := dns.NextLabel(qname, 0)
+
+	if strings.ToLower(qname[:i]) != who || ok {
+		err := context.ErrorMessage(dns.RcodeFormatError)
+		w.WriteMsg(err)
+		return dns.RcodeFormatError, errors.New(dns.RcodeToString[dns.RcodeFormatError])
+	}
+
+	answer := new(dns.Msg)
+	answer.SetReply(r)
+	answer.Compress = true
+	answer.Authoritative = true
+
+	ip := context.IP()
+	proto := context.Proto()
+	port, _ := context.Port()
+	family := context.Family()
+	var rr dns.RR
+
+	switch family {
+	case 1:
+		rr = new(dns.A)
+		rr.(*dns.A).Hdr = dns.RR_Header{Name: qname, Rrtype: dns.TypeA, Class: class, Ttl: 0}
+		rr.(*dns.A).A = net.ParseIP(ip).To4()
+	case 2:
+		rr = new(dns.AAAA)
+		rr.(*dns.AAAA).Hdr = dns.RR_Header{Name: qname, Rrtype: dns.TypeAAAA, Class: class, Ttl: 0}
+		rr.(*dns.AAAA).AAAA = net.ParseIP(ip)
+	}
+
+	t := new(dns.TXT)
+	t.Hdr = dns.RR_Header{Name: qname, Rrtype: dns.TypeTXT, Class: class, Ttl: 0}
+	t.Txt = []string{"Port: " + port + " (" + proto + ")"}
+
+	switch context.Type() {
+	case "TXT":
+		answer.Answer = append(answer.Answer, t)
+		answer.Extra = append(answer.Extra, rr)
+	default:
+		fallthrough
+	case "AAAA", "A":
+		answer.Answer = append(answer.Answer, rr)
+		answer.Extra = append(answer.Extra, t)
+	}
+	w.WriteMsg(answer)
+	return 0, nil
+}
+
+const who = "who."

middleware/reflect/reflect_test.go

@@ -0,0 +1 @@
+package reflect

middleware/replacer.go

@@ -0,0 +1,98 @@
+package middleware
+
+import (
+	"strconv"
+	"strings"
+	"time"
+
+	"github.com/miekg/dns"
+)
+
+// Replacer is a type which can replace placeholder
+// substrings in a string with actual values from a
+// http.Request and responseRecorder. Always use
+// NewReplacer to get one of these.
+type Replacer interface {
+	Replace(string) string
+	Set(key, value string)
+}
+
+type replacer struct {
+	replacements map[string]string
+	emptyValue   string
+}
+
+// NewReplacer makes a new replacer based on r and rr.
+// Do not create a new replacer until r and rr have all
+// the needed values, because this function copies those
+// values into the replacer. rr may be nil if it is not
+// available. emptyValue should be the string that is used
+// in place of empty string (can still be empty string).
+func NewReplacer(r *dns.Msg, rr *ResponseRecorder, emptyValue string) Replacer {
+	context := Context{W: rr, Req: r}
+	rep := replacer{
+		replacements: map[string]string{
+			"{type}":  context.Type(),
+			"{name}":  context.Name(),
+			"{class}": context.Class(),
+			"{proto}": context.Proto(),
+			"{when}": func() string {
+				return time.Now().Format(timeFormat)
+			}(),
+			"{remote}": context.IP(),
+			"{port}": func() string {
+				p, _ := context.Port()
+				return p
+			}(),
+		},
+		emptyValue: emptyValue,
+	}
+	if rr != nil {
+		rep.replacements["{rcode}"] = strconv.Itoa(rr.rcode)
+		rep.replacements["{size}"] = strconv.Itoa(rr.size)
+		rep.replacements["{latency}"] = time.Since(rr.start).String()
+	}
+
+	return rep
+}
+
+// Replace performs a replacement of values on s and returns
+// the string with the replaced values.
+func (r replacer) Replace(s string) string {
+	// Header replacements - these are case-insensitive, so we can't just use strings.Replace()
+	for strings.Contains(s, headerReplacer) {
+		idxStart := strings.Index(s, headerReplacer)
+		endOffset := idxStart + len(headerReplacer)
+		idxEnd := strings.Index(s[endOffset:], "}")
+		if idxEnd > -1 {
+			placeholder := strings.ToLower(s[idxStart : endOffset+idxEnd+1])
+			replacement := r.replacements[placeholder]
+			if replacement == "" {
+				replacement = r.emptyValue
+			}
+			s = s[:idxStart] + replacement + s[endOffset+idxEnd+1:]
+		} else {
+			break
+		}
+	}
+
+	// Regular replacements - these are easier because they're case-sensitive
+	for placeholder, replacement := range r.replacements {
+		if replacement == "" {
+			replacement = r.emptyValue
+		}
+		s = strings.Replace(s, placeholder, replacement, -1)
+	}
+
+	return s
+}
+
+// Set sets key to value in the replacements map.
+func (r replacer) Set(key, value string) {
+	r.replacements["{"+key+"}"] = value
+}
+
+const (
+	timeFormat     = "02/Jan/2006:15:04:05 -0700"
+	headerReplacer = "{>"
+)

middleware/replacer_test.go

@@ -0,0 +1,124 @@
+package middleware
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+)
+
+func TestNewReplacer(t *testing.T) {
+	w := httptest.NewRecorder()
+	recordRequest := NewResponseRecorder(w)
+	reader := strings.NewReader(`{"username": "dennis"}`)
+
+	request, err := http.NewRequest("POST", "http://localhost", reader)
+	if err != nil {
+		t.Fatal("Request Formation Failed\n")
+	}
+	replaceValues := NewReplacer(request, recordRequest, "")
+
+	switch v := replaceValues.(type) {
+	case replacer:
+
+		if v.replacements["{host}"] != "localhost" {
+			t.Error("Expected host to be localhost")
+		}
+		if v.replacements["{method}"] != "POST" {
+			t.Error("Expected request method  to be POST")
+		}
+		if v.replacements["{status}"] != "200" {
+			t.Error("Expected status to be 200")
+		}
+
+	default:
+		t.Fatal("Return Value from New Replacer expected pass type assertion into a replacer type\n")
+	}
+}
+
+func TestReplace(t *testing.T) {
+	w := httptest.NewRecorder()
+	recordRequest := NewResponseRecorder(w)
+	reader := strings.NewReader(`{"username": "dennis"}`)
+
+	request, err := http.NewRequest("POST", "http://localhost", reader)
+	if err != nil {
+		t.Fatal("Request Formation Failed\n")
+	}
+	request.Header.Set("Custom", "foobarbaz")
+	request.Header.Set("ShorterVal", "1")
+	repl := NewReplacer(request, recordRequest, "-")
+
+	if expected, actual := "This host is localhost.", repl.Replace("This host is {host}."); expected != actual {
+		t.Errorf("{host} replacement: expected '%s', got '%s'", expected, actual)
+	}
+	if expected, actual := "This request method is POST.", repl.Replace("This request method is {method}."); expected != actual {
+		t.Errorf("{method} replacement: expected '%s', got '%s'", expected, actual)
+	}
+	if expected, actual := "The response status is 200.", repl.Replace("The response status is {status}."); expected != actual {
+		t.Errorf("{status} replacement: expected '%s', got '%s'", expected, actual)
+	}
+	if expected, actual := "The Custom header is foobarbaz.", repl.Replace("The Custom header is {>Custom}."); expected != actual {
+		t.Errorf("{>Custom} replacement: expected '%s', got '%s'", expected, actual)
+	}
+
+	// Test header case-insensitivity
+	if expected, actual := "The cUsToM header is foobarbaz...", repl.Replace("The cUsToM header is {>cUsToM}..."); expected != actual {
+		t.Errorf("{>cUsToM} replacement: expected '%s', got '%s'", expected, actual)
+	}
+
+	// Test non-existent header/value
+	if expected, actual := "The Non-Existent header is -.", repl.Replace("The Non-Existent header is {>Non-Existent}."); expected != actual {
+		t.Errorf("{>Non-Existent} replacement: expected '%s', got '%s'", expected, actual)
+	}
+
+	// Test bad placeholder
+	if expected, actual := "Bad {host placeholder...", repl.Replace("Bad {host placeholder..."); expected != actual {
+		t.Errorf("bad placeholder: expected '%s', got '%s'", expected, actual)
+	}
+
+	// Test bad header placeholder
+	if expected, actual := "Bad {>Custom placeholder", repl.Replace("Bad {>Custom placeholder"); expected != actual {
+		t.Errorf("bad header placeholder: expected '%s', got '%s'", expected, actual)
+	}
+
+	// Test bad header placeholder with valid one later
+	if expected, actual := "Bad -", repl.Replace("Bad {>Custom placeholder {>ShorterVal}"); expected != actual {
+		t.Errorf("bad header placeholders: expected '%s', got '%s'", expected, actual)
+	}
+
+	// Test shorter header value with multiple placeholders
+	if expected, actual := "Short value 1 then foobarbaz.", repl.Replace("Short value {>ShorterVal} then {>Custom}."); expected != actual {
+		t.Errorf("short value: expected '%s', got '%s'", expected, actual)
+	}
+}
+
+func TestSet(t *testing.T) {
+	w := httptest.NewRecorder()
+	recordRequest := NewResponseRecorder(w)
+	reader := strings.NewReader(`{"username": "dennis"}`)
+
+	request, err := http.NewRequest("POST", "http://localhost", reader)
+	if err != nil {
+		t.Fatalf("Request Formation Failed \n")
+	}
+	repl := NewReplacer(request, recordRequest, "")
+
+	repl.Set("host", "getcaddy.com")
+	repl.Set("method", "GET")
+	repl.Set("status", "201")
+	repl.Set("variable", "value")
+
+	if repl.Replace("This host is {host}") != "This host is getcaddy.com" {
+		t.Error("Expected host replacement failed")
+	}
+	if repl.Replace("This request method is {method}") != "This request method is GET" {
+		t.Error("Expected method replacement failed")
+	}
+	if repl.Replace("The response status is {status}") != "The response status is 201" {
+		t.Error("Expected status replacement failed")
+	}
+	if repl.Replace("The value of variable is {variable}") != "The value of variable is value" {
+		t.Error("Expected variable replacement failed")
+	}
+}

middleware/rewrite/condition.go

@@ -0,0 +1,130 @@
+package rewrite
+
+import (
+	"fmt"
+	"regexp"
+	"strings"
+
+	"github.com/miekg/coredns/middleware"
+	"github.com/miekg/dns"
+)
+
+// Operators
+const (
+	Is         = "is"
+	Not        = "not"
+	Has        = "has"
+	NotHas     = "not_has"
+	StartsWith = "starts_with"
+	EndsWith   = "ends_with"
+	Match      = "match"
+	NotMatch   = "not_match"
+)
+
+func operatorError(operator string) error {
+	return fmt.Errorf("Invalid operator %v", operator)
+}
+
+func newReplacer(r *dns.Msg) middleware.Replacer {
+	return middleware.NewReplacer(r, nil, "")
+}
+
+// condition is a rewrite condition.
+type condition func(string, string) bool
+
+var conditions = map[string]condition{
+	Is:         isFunc,
+	Not:        notFunc,
+	Has:        hasFunc,
+	NotHas:     notHasFunc,
+	StartsWith: startsWithFunc,
+	EndsWith:   endsWithFunc,
+	Match:      matchFunc,
+	NotMatch:   notMatchFunc,
+}
+
+// isFunc is condition for Is operator.
+// It checks for equality.
+func isFunc(a, b string) bool {
+	return a == b
+}
+
+// notFunc is condition for Not operator.
+// It checks for inequality.
+func notFunc(a, b string) bool {
+	return a != b
+}
+
+// hasFunc is condition for Has operator.
+// It checks if b is a substring of a.
+func hasFunc(a, b string) bool {
+	return strings.Contains(a, b)
+}
+
+// notHasFunc is condition for NotHas operator.
+// It checks if b is not a substring of a.
+func notHasFunc(a, b string) bool {
+	return !strings.Contains(a, b)
+}
+
+// startsWithFunc is condition for StartsWith operator.
+// It checks if b is a prefix of a.
+func startsWithFunc(a, b string) bool {
+	return strings.HasPrefix(a, b)
+}
+
+// endsWithFunc is condition for EndsWith operator.
+// It checks if b is a suffix of a.
+func endsWithFunc(a, b string) bool {
+	return strings.HasSuffix(a, b)
+}
+
+// matchFunc is condition for Match operator.
+// It does regexp matching of a against pattern in b
+// and returns if they match.
+func matchFunc(a, b string) bool {
+	matched, _ := regexp.MatchString(b, a)
+	return matched
+}
+
+// notMatchFunc is condition for NotMatch operator.
+// It does regexp matching of a against pattern in b
+// and returns if they do not match.
+func notMatchFunc(a, b string) bool {
+	matched, _ := regexp.MatchString(b, a)
+	return !matched
+}
+
+// If is statement for a rewrite condition.
+type If struct {
+	A        string
+	Operator string
+	B        string
+}
+
+// True returns true if the condition is true and false otherwise.
+// If r is not nil, it replaces placeholders before comparison.
+func (i If) True(r *dns.Msg) bool {
+	if c, ok := conditions[i.Operator]; ok {
+		a, b := i.A, i.B
+		if r != nil {
+			replacer := newReplacer(r)
+			a = replacer.Replace(i.A)
+			b = replacer.Replace(i.B)
+		}
+		return c(a, b)
+	}
+	return false
+}
+
+// NewIf creates a new If condition.
+func NewIf(a, operator, b string) (If, error) {
+	if _, ok := conditions[operator]; !ok {
+		return If{}, operatorError(operator)
+	}
+	return If{
+		A:        a,
+		Operator: operator,
+		B:        b,
+	}, nil
+}

middleware/rewrite/condition_test.go

@@ -0,0 +1,106 @@
+package rewrite
+
+import (
+	"net/http"
+	"strings"
+	"testing"
+)
+
+func TestConditions(t *testing.T) {
+	tests := []struct {
+		condition string
+		isTrue    bool
+	}{
+		{"a is b", false},
+		{"a is a", true},
+		{"a not b", true},
+		{"a not a", false},
+		{"a has a", true},
+		{"a has b", false},
+		{"ba has b", true},
+		{"bab has b", true},
+		{"bab has bb", false},
+		{"a not_has a", false},
+		{"a not_has b", true},
+		{"ba not_has b", false},
+		{"bab not_has b", false},
+		{"bab not_has bb", true},
+		{"bab starts_with bb", false},
+		{"bab starts_with ba", true},
+		{"bab starts_with bab", true},
+		{"bab ends_with bb", false},
+		{"bab ends_with bab", true},
+		{"bab ends_with ab", true},
+		{"a match *", false},
+		{"a match a", true},
+		{"a match .*", true},
+		{"a match a.*", true},
+		{"a match b.*", false},
+		{"ba match b.*", true},
+		{"ba match b[a-z]", true},
+		{"b0 match b[a-z]", false},
+		{"b0a match b[a-z]", false},
+		{"b0a match b[a-z]+", false},
+		{"b0a match b[a-z0-9]+", true},
+		{"a not_match *", true},
+		{"a not_match a", false},
+		{"a not_match .*", false},
+		{"a not_match a.*", false},
+		{"a not_match b.*", true},
+		{"ba not_match b.*", false},
+		{"ba not_match b[a-z]", false},
+		{"b0 not_match b[a-z]", true},
+		{"b0a not_match b[a-z]", true},
+		{"b0a not_match b[a-z]+", true},
+		{"b0a not_match b[a-z0-9]+", false},
+	}
+
+	for i, test := range tests {
+		str := strings.Fields(test.condition)
+		ifCond, err := NewIf(str[0], str[1], str[2])
+		if err != nil {
+			t.Error(err)
+		}
+		isTrue := ifCond.True(nil)
+		if isTrue != test.isTrue {
+			t.Errorf("Test %v: expected %v found %v", i, test.isTrue, isTrue)
+		}
+	}
+
+	invalidOperators := []string{"ss", "and", "if"}
+	for _, op := range invalidOperators {
+		_, err := NewIf("a", op, "b")
+		if err == nil {
+			t.Errorf("Invalid operator %v used, expected error.", op)
+		}
+	}
+
+	replaceTests := []struct {
+		url       string
+		condition string
+		isTrue    bool
+	}{
+		{"/home", "{uri} match /home", true},
+		{"/hom", "{uri} match /home", false},
+		{"/hom", "{uri} starts_with /home", false},
+		{"/hom", "{uri} starts_with /h", true},
+		{"/home/.hiddenfile", `{uri} match \/\.(.*)`, true},
+		{"/home/.hiddendir/afile", `{uri} match \/\.(.*)`, true},
+	}
+
+	for i, test := range replaceTests {
+		r, err := http.NewRequest("GET", test.url, nil)
+		if err != nil {
+			t.Error(err)
+		}
+		str := strings.Fields(test.condition)
+		ifCond, err := NewIf(str[0], str[1], str[2])
+		if err != nil {
+			t.Error(err)
+		}
+		isTrue := ifCond.True(r)
+		if isTrue != test.isTrue {
+			t.Errorf("Test %v: expected %v found %v", i, test.isTrue, isTrue)
+		}
+	}
+}

middleware/rewrite/reverter.go

@@ -0,0 +1,38 @@
+package rewrite
+
+import "github.com/miekg/dns"
+
+// ResponseRevert reverses the operations done on the question section of a packet.
+// This is need because the client will otherwise disregards the response, i.e.
+// dig will complain with ';; Question section mismatch: got miek.nl/HINFO/IN'
+type ResponseReverter struct {
+	dns.ResponseWriter
+	original dns.Question
+}
+
+func NewResponseReverter(w dns.ResponseWriter, r *dns.Msg) *ResponseReverter {
+	return &ResponseReverter{
+		ResponseWriter: w,
+		original:       r.Question[0],
+	}
+}
+
+// WriteMsg records the status code and calls the
+// underlying ResponseWriter's WriteMsg method.
+func (r *ResponseReverter) WriteMsg(res *dns.Msg) error {
+	res.Question[0] = r.original
+	return r.ResponseWriter.WriteMsg(res)
+}
+
+// Write is a wrapper that records the size of the message that gets written.
+func (r *ResponseReverter) Write(buf []byte) (int, error) {
+	n, err := r.ResponseWriter.Write(buf)
+	return n, err
+}
+
+// Hijack implements dns.Hijacker. It simply wraps the underlying
+// ResponseWriter's Hijack method if there is one, or returns an error.
+func (r *ResponseReverter) Hijack() {
+	r.ResponseWriter.Hijack()
+	return
+}

middleware/rewrite/rewrite.go

@@ -0,0 +1,223 @@
+// Package rewrite is middleware for rewriting requests internally to
+// something different.
+package rewrite
+
+import (
+	"github.com/miekg/coredns/middleware"
+	"github.com/miekg/dns"
+)
+
+// Result is the result of a rewrite
+type Result int
+
+const (
+	// RewriteIgnored is returned when rewrite is not done on request.
+	RewriteIgnored Result = iota
+	// RewriteDone is returned when rewrite is done on request.
+	RewriteDone
+	// RewriteStatus is returned when rewrite is not needed and status code should be set
+	// for the request.
+	RewriteStatus
+)
+
+// Rewrite is middleware to rewrite requests internally before being handled.
+type Rewrite struct {
+	Next  middleware.Handler
+	Rules []Rule
+}
+
+// ServeHTTP implements the middleware.Handler interface.
+func (rw Rewrite) ServeDNS(w dns.ResponseWriter, r *dns.Msg) (int, error) {
+	wr := NewResponseReverter(w, r)
+	for _, rule := range rw.Rules {
+		switch result := rule.Rewrite(r); result {
+		case RewriteDone:
+			return rw.Next.ServeDNS(wr, r)
+		case RewriteIgnored:
+			break
+		case RewriteStatus:
+			// only valid for complex rules.
+			// if cRule, ok := rule.(*ComplexRule); ok && cRule.Status != 0 {
+			// return cRule.Status, nil
+			// }
+		}
+	}
+	return rw.Next.ServeDNS(w, r)
+}
+
+// Rule describes an internal location rewrite rule.
+type Rule interface {
+	// Rewrite rewrites the internal location of the current request.
+	Rewrite(*dns.Msg) Result
+}
+
+// SimpleRule is a simple rewrite rule. If the From and To look like a type
+// the type of the request is rewritten, otherwise the name is.
+// Note: TSIG signed requests will be invalid.
+type SimpleRule struct {
+	From, To         string
+	fromType, toType uint16
+}
+
+// NewSimpleRule creates a new Simple Rule
+func NewSimpleRule(from, to string) SimpleRule {
+	tpf := dns.StringToType[from]
+	tpt := dns.StringToType[to]
+
+	return SimpleRule{From: from, To: to, fromType: tpf, toType: tpt}
+}
+
+// Rewrite rewrites the the current request.
+func (s SimpleRule) Rewrite(r *dns.Msg) Result {
+	if s.fromType > 0 && s.toType > 0 {
+		if r.Question[0].Qtype == s.fromType {
+			r.Question[0].Qtype = s.toType
+			return RewriteDone
+		}
+
+	}
+
+	// if the question name matches the full name, or subset rewrite that
+	// s.Question[0].Name
+	return RewriteIgnored
+}
+
+/*
+// ComplexRule is a rewrite rule based on a regular expression
+type ComplexRule struct {
+	// Path base. Request to this path and subpaths will be rewritten
+	Base string
+
+	// Path to rewrite to
+	To string
+
+	// If set, neither performs rewrite nor proceeds
+	// with request. Only returns code.
+	Status int
+
+	// Extensions to filter by
+	Exts []string
+
+	// Rewrite conditions
+	Ifs []If
+
+	*regexp.Regexp
+}
+
+// NewComplexRule creates a new RegexpRule. It returns an error if regexp
+// pattern (pattern) or extensions (ext) are invalid.
+func NewComplexRule(base, pattern, to string, status int, ext []string, ifs []If) (*ComplexRule, error) {
+	// validate regexp if present
+	var r *regexp.Regexp
+	if pattern != "" {
+		var err error
+		r, err = regexp.Compile(pattern)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	// validate extensions if present
+	for _, v := range ext {
+		if len(v) < 2 || (len(v) < 3 && v[0] == '!') {
+			// check if no extension is specified
+			if v != "/" && v != "!/" {
+				return nil, fmt.Errorf("invalid extension %v", v)
+			}
+		}
+	}
+
+	return &ComplexRule{
+		Base:   base,
+		To:     to,
+		Status: status,
+		Exts:   ext,
+		Ifs:    ifs,
+		Regexp: r,
+	}, nil
+}
+
+// Rewrite rewrites the internal location of the current request.
+func (r *ComplexRule) Rewrite(req *dns.Msg) (re Result) {
+	rPath := req.URL.Path
+	replacer := newReplacer(req)
+
+	// validate base
+	if !middleware.Path(rPath).Matches(r.Base) {
+		return
+	}
+
+	// validate extensions
+	if !r.matchExt(rPath) {
+		return
+	}
+
+	// validate regexp if present
+	if r.Regexp != nil {
+		// include trailing slash in regexp if present
+		start := len(r.Base)
+		if strings.HasSuffix(r.Base, "/") {
+			start--
+		}
+
+		matches := r.FindStringSubmatch(rPath[start:])
+		switch len(matches) {
+		case 0:
+			// no match
+			return
+		default:
+			// set regexp match variables {1}, {2} ...
+			for i := 1; i < len(matches); i++ {
+				replacer.Set(fmt.Sprint(i), matches[i])
+			}
+		}
+	}
+
+	// validate rewrite conditions
+	for _, i := range r.Ifs {
+		if !i.True(req) {
+			return
+		}
+	}
+
+	// if status is present, stop rewrite and return it.
+	if r.Status != 0 {
+		return RewriteStatus
+	}
+
+	// attempt rewrite
+	return To(fs, req, r.To, replacer)
+}
+
+// matchExt matches rPath against registered file extensions.
+// Returns true if a match is found and false otherwise.
+func (r *ComplexRule) matchExt(rPath string) bool {
+	f := filepath.Base(rPath)
+	ext := path.Ext(f)
+	if ext == "" {
+		ext = "/"
+	}
+
+	mustUse := false
+	for _, v := range r.Exts {
+		use := true
+		if v[0] == '!' {
+			use = false
+			v = v[1:]
+		}
+
+		if use {
+			mustUse = true
+		}
+
+		if ext == v {
+			return use
+		}
+	}
+
+	if mustUse {
+		return false
+	}
+	return true
+}
+*/

middleware/rewrite/rewrite_test.go

@@ -0,0 +1,159 @@
+package rewrite
+
+import (
+	"fmt"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+
+	"github.com/miekg/coredns/middleware"
+)
+
+func TestRewrite(t *testing.T) {
+	rw := Rewrite{
+		Next: middleware.HandlerFunc(urlPrinter),
+		Rules: []Rule{
+			NewSimpleRule("/from", "/to"),
+			NewSimpleRule("/a", "/b"),
+			NewSimpleRule("/b", "/b{uri}"),
+		},
+		FileSys: http.Dir("."),
+	}
+
+	regexps := [][]string{
+		{"/reg/", ".*", "/to", ""},
+		{"/r/", "[a-z]+", "/toaz", "!.html|"},
+		{"/url/", "a([a-z0-9]*)s([A-Z]{2})", "/to/{path}", ""},
+		{"/ab/", "ab", "/ab?{query}", ".txt|"},
+		{"/ab/", "ab", "/ab?type=html&{query}", ".html|"},
+		{"/abc/", "ab", "/abc/{file}", ".html|"},
+		{"/abcd/", "ab", "/a/{dir}/{file}", ".html|"},
+		{"/abcde/", "ab", "/a#{fragment}", ".html|"},
+		{"/ab/", `.*\.jpg`, "/ajpg", ""},
+		{"/reggrp", `/ad/([0-9]+)([a-z]*)`, "/a{1}/{2}", ""},
+		{"/reg2grp", `(.*)`, "/{1}", ""},
+		{"/reg3grp", `(.*)/(.*)/(.*)`, "/{1}{2}{3}", ""},
+	}
+
+	for _, regexpRule := range regexps {
+		var ext []string
+		if s := strings.Split(regexpRule[3], "|"); len(s) > 1 {
+			ext = s[:len(s)-1]
+		}
+		rule, err := NewComplexRule(regexpRule[0], regexpRule[1], regexpRule[2], 0, ext, nil)
+		if err != nil {
+			t.Fatal(err)
+		}
+		rw.Rules = append(rw.Rules, rule)
+	}
+
+	tests := []struct {
+		from       string
+		expectedTo string
+	}{
+		{"/from", "/to"},
+		{"/a", "/b"},
+		{"/b", "/b/b"},
+		{"/aa", "/aa"},
+		{"/", "/"},
+		{"/a?foo=bar", "/b?foo=bar"},
+		{"/asdf?foo=bar", "/asdf?foo=bar"},
+		{"/foo#bar", "/foo#bar"},
+		{"/a#foo", "/b#foo"},
+		{"/reg/foo", "/to"},
+		{"/re", "/re"},
+		{"/r/", "/r/"},
+		{"/r/123", "/r/123"},
+		{"/r/a123", "/toaz"},
+		{"/r/abcz", "/toaz"},
+		{"/r/z", "/toaz"},
+		{"/r/z.html", "/r/z.html"},
+		{"/r/z.js", "/toaz"},
+		{"/url/asAB", "/to/url/asAB"},
+		{"/url/aBsAB", "/url/aBsAB"},
+		{"/url/a00sAB", "/to/url/a00sAB"},
+		{"/url/a0z0sAB", "/to/url/a0z0sAB"},
+		{"/ab/aa", "/ab/aa"},
+		{"/ab/ab", "/ab/ab"},
+		{"/ab/ab.txt", "/ab"},
+		{"/ab/ab.txt?name=name", "/ab?name=name"},
+		{"/ab/ab.html?name=name", "/ab?type=html&name=name"},
+		{"/abc/ab.html", "/abc/ab.html"},
+		{"/abcd/abcd.html", "/a/abcd/abcd.html"},
+		{"/abcde/abcde.html", "/a"},
+		{"/abcde/abcde.html#1234", "/a#1234"},
+		{"/ab/ab.jpg", "/ajpg"},
+		{"/reggrp/ad/12", "/a12"},
+		{"/reggrp/ad/124a", "/a124/a"},
+		{"/reggrp/ad/124abc", "/a124/abc"},
+		{"/reg2grp/ad/124abc", "/ad/124abc"},
+		{"/reg3grp/ad/aa/66", "/adaa66"},
+		{"/reg3grp/ad612/n1n/ab", "/ad612n1nab"},
+	}
+
+	for i, test := range tests {
+		req, err := http.NewRequest("GET", test.from, nil)
+		if err != nil {
+			t.Fatalf("Test %d: Could not create HTTP request: %v", i, err)
+		}
+
+		rec := httptest.NewRecorder()
+		rw.ServeHTTP(rec, req)
+
+		if rec.Body.String() != test.expectedTo {
+			t.Errorf("Test %d: Expected URL to be '%s' but was '%s'",
+				i, test.expectedTo, rec.Body.String())
+		}
+	}
+
+	statusTests := []struct {
+		status         int
+		base           string
+		to             string
+		regexp         string
+		statusExpected bool
+	}{
+		{400, "/status", "", "", true},
+		{400, "/ignore", "", "", false},
+		{400, "/", "", "^/ignore", false},
+		{400, "/", "", "(.*)", true},
+		{400, "/status", "", "", true},
+	}
+
+	for i, s := range statusTests {
+		urlPath := fmt.Sprintf("/status%d", i)
+		rule, err := NewComplexRule(s.base, s.regexp, s.to, s.status, nil, nil)
+		if err != nil {
+			t.Fatalf("Test %d: No error expected for rule but found %v", i, err)
+		}
+		rw.Rules = []Rule{rule}
+		req, err := http.NewRequest("GET", urlPath, nil)
+		if err != nil {
+			t.Fatalf("Test %d: Could not create HTTP request: %v", i, err)
+		}
+
+		rec := httptest.NewRecorder()
+		code, err := rw.ServeHTTP(rec, req)
+		if err != nil {
+			t.Fatalf("Test %d: No error expected for handler but found %v", i, err)
+		}
+		if s.statusExpected {
+			if rec.Body.String() != "" {
+				t.Errorf("Test %d: Expected empty body but found %s", i, rec.Body.String())
+			}
+			if code != s.status {
+				t.Errorf("Test %d: Expected status code %d found %d", i, s.status, code)
+			}
+		} else {
+			if code != 0 {
+				t.Errorf("Test %d: Expected no status code found %d", i, code)
+			}
+		}
+	}
+}
+
+func urlPrinter(w http.ResponseWriter, r *http.Request) (int, error) {
+	fmt.Fprintf(w, r.URL.String())
+	return 0, nil
+}

middleware/rewrite/testdata/testfile

@@ -0,0 +1 @@
+empty

middleware/roller.go

@@ -0,0 +1,27 @@
+package middleware
+
+import (
+	"io"
+
+	"gopkg.in/natefinch/lumberjack.v2"
+)
+
+// LogRoller implements a middleware that provides a rolling logger.
+type LogRoller struct {
+	Filename   string
+	MaxSize    int
+	MaxAge     int
+	MaxBackups int
+	LocalTime  bool
+}
+
+// GetLogWriter returns an io.Writer that writes to a rolling logger.
+func (l LogRoller) GetLogWriter() io.Writer {
+	return &lumberjack.Logger{
+		Filename:   l.Filename,
+		MaxSize:    l.MaxSize,
+		MaxAge:     l.MaxAge,
+		MaxBackups: l.MaxBackups,
+		LocalTime:  l.LocalTime,
+	}
+}

middleware/zone.go

@@ -0,0 +1,21 @@
+package middleware
+
+import "strings"
+
+type Zones []string
+
+// Matches checks to see if other matches p.
+// The match will return the most specific zones
+// that matches other. The empty string signals a not found
+// condition.
+func (z Zones) Matches(qname string) string {
+	zone := ""
+	for _, zname := range z {
+		if strings.HasSuffix(qname, zname) {
+			if len(zname) > len(zone) {
+				zone = zname
+			}
+		}
+	}
+	return zone
+}