Remove the word middleware (#1067)

* Rename middleware to plugin

first pass; mostly used 'sed', few spots where I manually changed
text.

This still builds a coredns binary.

* fmt error

* Rename AddMiddleware to AddPlugin

* Readd AddMiddleware to remain backwards compat

plugin/autopath/setup_test.go

@@ -0,0 +1,77 @@
+package autopath
+
+import (
+	"os"
+	"reflect"
+	"strings"
+	"testing"
+
+	"github.com/coredns/coredns/plugin/test"
+
+	"github.com/mholt/caddy"
+)
+
+func TestSetupAutoPath(t *testing.T) {
+	resolv, rm, err := test.TempFile(os.TempDir(), resolvConf)
+	if err != nil {
+		t.Fatalf("Could not create resolv.conf test file %s: %s", resolvConf, err)
+	}
+	defer rm()
+
+	tests := []struct {
+		input              string
+		shouldErr          bool
+		expectedZone       string
+		expectedMw         string   // expected plugin.
+		expectedSearch     []string // expected search path
+		expectedErrContent string   // substring from the expected error. Empty for positive cases.
+	}{
+		// positive
+		{`autopath @kubernetes`, false, "", "kubernetes", nil, ""},
+		{`autopath example.org @kubernetes`, false, "example.org.", "kubernetes", nil, ""},
+		{`autopath 10.0.0.0/8 @kubernetes`, false, "10.in-addr.arpa.", "kubernetes", nil, ""},
+		{`autopath ` + resolv, false, "", "", []string{"bar.com.", "baz.com.", ""}, ""},
+		// negative
+		{`autopath kubernetes`, true, "", "", nil, "open kubernetes: no such file or directory"},
+		{`autopath`, true, "", "", nil, "no resolv-conf"},
+	}
+
+	for i, test := range tests {
+		c := caddy.NewTestController("dns", test.input)
+		ap, mw, err := autoPathParse(c)
+
+		if test.shouldErr && err == nil {
+			t.Errorf("Test %d: Expected error but found %s for input %s", i, err, test.input)
+		}
+
+		if err != nil {
+			if !test.shouldErr {
+				t.Errorf("Test %d: Expected no error but found one for input %s. Error was: %v", i, test.input, err)
+			}
+
+			if !strings.Contains(err.Error(), test.expectedErrContent) {
+				t.Errorf("Test %d: Expected error to contain: %v, found error: %v, input: %s", i, test.expectedErrContent, err, test.input)
+			}
+		}
+
+		if !test.shouldErr && mw != test.expectedMw {
+			t.Errorf("Test %d, Middleware not correctly set for input %s. Expected: %s, actual: %s", i, test.input, test.expectedMw, mw)
+		}
+		if !test.shouldErr && ap.search != nil {
+			if !reflect.DeepEqual(test.expectedSearch, ap.search) {
+				t.Errorf("Test %d, wrong searchpath for input %s. Expected: '%v', actual: '%v'", i, test.input, test.expectedSearch, ap.search)
+			}
+		}
+		if !test.shouldErr && test.expectedZone != "" {
+			if test.expectedZone != ap.Zones[0] {
+				t.Errorf("Test %d, expected zone %q for input %s, got: %q", i, test.expectedZone, test.input, ap.Zones[0])
+			}
+		}
+	}
+}
+
+const resolvConf = `nameserver 1.2.3.4
+domain foo.com
+search bar.com baz.com
+options ndots:5
+`