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/file/secondary_test.go

@@ -0,0 +1,168 @@
+package file
+
+import (
+	"fmt"
+	"io/ioutil"
+	"log"
+	"testing"
+
+	"github.com/coredns/coredns/plugin/test"
+	"github.com/coredns/coredns/request"
+
+	"github.com/miekg/dns"
+)
+
+// TODO(miek): should test notifies as well, ie start test server (a real coredns one)...
+// setup other test server that sends notify, see if CoreDNS comes calling for a zone
+// tranfer
+
+func TestLess(t *testing.T) {
+	const (
+		min  = 0
+		max  = 4294967295
+		low  = 12345
+		high = 4000000000
+	)
+
+	if less(min, max) {
+		t.Fatalf("less: should be false")
+	}
+	if !less(max, min) {
+		t.Fatalf("less: should be true")
+	}
+	if !less(high, low) {
+		t.Fatalf("less: should be true")
+	}
+	if !less(7, 9) {
+		t.Fatalf("less; should be true")
+	}
+}
+
+type soa struct {
+	serial uint32
+}
+
+func (s *soa) Handler(w dns.ResponseWriter, req *dns.Msg) {
+	m := new(dns.Msg)
+	m.SetReply(req)
+	switch req.Question[0].Qtype {
+	case dns.TypeSOA:
+		m.Answer = make([]dns.RR, 1)
+		m.Answer[0] = test.SOA(fmt.Sprintf("%s IN SOA bla. bla. %d 0 0 0 0 ", testZone, s.serial))
+		w.WriteMsg(m)
+	case dns.TypeAXFR:
+		m.Answer = make([]dns.RR, 4)
+		m.Answer[0] = test.SOA(fmt.Sprintf("%s IN SOA bla. bla. %d 0 0 0 0 ", testZone, s.serial))
+		m.Answer[1] = test.A(fmt.Sprintf("%s IN A 127.0.0.1", testZone))
+		m.Answer[2] = test.A(fmt.Sprintf("%s IN A 127.0.0.1", testZone))
+		m.Answer[3] = test.SOA(fmt.Sprintf("%s IN SOA bla. bla. %d 0 0 0 0 ", testZone, s.serial))
+		w.WriteMsg(m)
+	}
+}
+
+func (s *soa) TransferHandler(w dns.ResponseWriter, req *dns.Msg) {
+	m := new(dns.Msg)
+	m.SetReply(req)
+	m.Answer = make([]dns.RR, 1)
+	m.Answer[0] = test.SOA(fmt.Sprintf("%s IN SOA bla. bla. %d 0 0 0 0 ", testZone, s.serial))
+	w.WriteMsg(m)
+}
+
+const testZone = "secondary.miek.nl."
+
+func TestShouldTransfer(t *testing.T) {
+	soa := soa{250}
+	log.SetOutput(ioutil.Discard)
+
+	dns.HandleFunc(testZone, soa.Handler)
+	defer dns.HandleRemove(testZone)
+
+	s, addrstr, err := test.TCPServer("127.0.0.1:0")
+	if err != nil {
+		t.Fatalf("unable to run test server: %v", err)
+	}
+	defer s.Shutdown()
+
+	z := new(Zone)
+	z.origin = testZone
+	z.TransferFrom = []string{addrstr}
+
+	// when we have a nil SOA (initial state)
+	should, err := z.shouldTransfer()
+	if err != nil {
+		t.Fatalf("unable to run shouldTransfer: %v", err)
+	}
+	if !should {
+		t.Fatalf("shouldTransfer should return true for serial: %d", soa.serial)
+	}
+	// Serial smaller
+	z.Apex.SOA = test.SOA(fmt.Sprintf("%s IN SOA bla. bla. %d 0 0 0 0 ", testZone, soa.serial-1))
+	should, err = z.shouldTransfer()
+	if err != nil {
+		t.Fatalf("unable to run shouldTransfer: %v", err)
+	}
+	if !should {
+		t.Fatalf("shouldTransfer should return true for serial: %q", soa.serial-1)
+	}
+	// Serial equal
+	z.Apex.SOA = test.SOA(fmt.Sprintf("%s IN SOA bla. bla. %d 0 0 0 0 ", testZone, soa.serial))
+	should, err = z.shouldTransfer()
+	if err != nil {
+		t.Fatalf("unable to run shouldTransfer: %v", err)
+	}
+	if should {
+		t.Fatalf("shouldTransfer should return false for serial: %d", soa.serial)
+	}
+}
+
+func TestTransferIn(t *testing.T) {
+	soa := soa{250}
+	log.SetOutput(ioutil.Discard)
+
+	dns.HandleFunc(testZone, soa.Handler)
+	defer dns.HandleRemove(testZone)
+
+	s, addrstr, err := test.TCPServer("127.0.0.1:0")
+	if err != nil {
+		t.Fatalf("unable to run test server: %v", err)
+	}
+	defer s.Shutdown()
+
+	z := new(Zone)
+	z.Expired = new(bool)
+	z.origin = testZone
+	z.TransferFrom = []string{addrstr}
+
+	err = z.TransferIn()
+	if err != nil {
+		t.Fatalf("unable to run TransferIn: %v", err)
+	}
+	if z.Apex.SOA.String() != fmt.Sprintf("%s	3600	IN	SOA	bla. bla. 250 0 0 0 0", testZone) {
+		t.Fatalf("unknown SOA transferred")
+	}
+}
+
+func TestIsNotify(t *testing.T) {
+	z := new(Zone)
+	z.Expired = new(bool)
+	z.origin = testZone
+	state := newRequest(testZone, dns.TypeSOA)
+	// need to set opcode
+	state.Req.Opcode = dns.OpcodeNotify
+
+	z.TransferFrom = []string{"10.240.0.1:53"} // IP from from testing/responseWriter
+	if !z.isNotify(state) {
+		t.Fatal("should have been valid notify")
+	}
+	z.TransferFrom = []string{"10.240.0.2:53"}
+	if z.isNotify(state) {
+		t.Fatal("should have been invalid notify")
+	}
+}
+
+func newRequest(zone string, qtype uint16) request.Request {
+	m := new(dns.Msg)
+	m.SetQuestion("example.com.", dns.TypeA)
+	m.SetEdns0(4097, true)
+	return request.Request{W: &test.ResponseWriter{}, Req: m}
+}