Better naming (#2104)

* Move functions from pkg/transport to pkg/parse

Although "parse" is a fairly generic name I believe this is somewhat
better named. pkg/transport keeps a few constants that are uses
throughout for the rest is is renaming a bunch (and the fallout from
there to make things compile again).

Signed-off-by: Miek Gieben <miek@miek.nl>

* Fix tests

Signed-off-by: Miek Gieben <miek@miek.nl>

plugin/pkg/parse/host.go

@@ -0,0 +1,98 @@
+package parse
+
+import (
+	"fmt"
+	"net"
+	"os"
+
+	"github.com/coredns/coredns/plugin/pkg/transport"
+
+	"github.com/miekg/dns"
+)
+
+// HostPortOrFile parses the strings in s, each string can either be a
+// address, [scheme://]address:port or a filename. The address part is checked
+// and in case of filename a resolv.conf like file is (assumed) and parsed and
+// the nameservers found are returned.
+func HostPortOrFile(s ...string) ([]string, error) {
+	var servers []string
+	for _, h := range s {
+
+		trans, host := Transport(h)
+
+		addr, _, err := net.SplitHostPort(host)
+		if err != nil {
+			// Parse didn't work, it is not a addr:port combo
+			if net.ParseIP(host) == nil {
+				// Not an IP address.
+				ss, err := tryFile(host)
+				if err == nil {
+					servers = append(servers, ss...)
+					continue
+				}
+				return servers, fmt.Errorf("not an IP address or file: %q", host)
+			}
+			var ss string
+			switch trans {
+			case transport.DNS:
+				ss = net.JoinHostPort(host, transport.Port)
+			case transport.TLS:
+				ss = transport.TLS + "://" + net.JoinHostPort(host, transport.TLSPort)
+			case transport.GRPC:
+				ss = transport.GRPC + "://" + net.JoinHostPort(host, transport.GRPCPort)
+			case transport.HTTPS:
+				ss = transport.HTTPS + "://" + net.JoinHostPort(host, transport.HTTPSPort)
+			}
+			servers = append(servers, ss)
+			continue
+		}
+
+		if net.ParseIP(addr) == nil {
+			// Not an IP address.
+			ss, err := tryFile(host)
+			if err == nil {
+				servers = append(servers, ss...)
+				continue
+			}
+			return servers, fmt.Errorf("not an IP address or file: %q", host)
+		}
+		servers = append(servers, h)
+	}
+	return servers, nil
+}
+
+// Try to open this is a file first.
+func tryFile(s string) ([]string, error) {
+	c, err := dns.ClientConfigFromFile(s)
+	if err == os.ErrNotExist {
+		return nil, fmt.Errorf("failed to open file %q: %q", s, err)
+	} else if err != nil {
+		return nil, err
+	}
+
+	servers := []string{}
+	for _, s := range c.Servers {
+		servers = append(servers, net.JoinHostPort(s, c.Port))
+	}
+	return servers, nil
+}
+
+// HostPort will check if the host part is a valid IP address, if the
+// IP address is valid, but no port is found, defaultPort is added.
+func HostPort(s, defaultPort string) (string, error) {
+	addr, port, err := net.SplitHostPort(s)
+	if port == "" {
+		port = defaultPort
+	}
+	if err != nil {
+		if net.ParseIP(s) == nil {
+			return "", fmt.Errorf("must specify an IP address: `%s'", s)
+		}
+		return net.JoinHostPort(s, port), nil
+	}
+
+	if net.ParseIP(addr) == nil {
+		return "", fmt.Errorf("must specify an IP address: `%s'", addr)
+	}
+	return net.JoinHostPort(addr, port), nil
+}

plugin/pkg/parse/host_test.go

@@ -0,0 +1,87 @@
+package parse
+
+import (
+	"io/ioutil"
+	"os"
+	"testing"
+
+	"github.com/coredns/coredns/plugin/pkg/transport"
+)
+
+func TestHostPortOrFile(t *testing.T) {
+	tests := []struct {
+		in        string
+		expected  string
+		shouldErr bool
+	}{
+		{
+			"8.8.8.8",
+			"8.8.8.8:53",
+			false,
+		},
+		{
+			"8.8.8.8:153",
+			"8.8.8.8:153",
+			false,
+		},
+		{
+			"/etc/resolv.conf:53",
+			"",
+			true,
+		},
+		{
+			"resolv.conf",
+			"127.0.0.1:53",
+			false,
+		},
+	}
+
+	err := ioutil.WriteFile("resolv.conf", []byte("nameserver 127.0.0.1\n"), 0600)
+	if err != nil {
+		t.Fatalf("Failed to write test resolv.conf")
+	}
+	defer os.Remove("resolv.conf")
+
+	for i, tc := range tests {
+		got, err := HostPortOrFile(tc.in)
+		if err == nil && tc.shouldErr {
+			t.Errorf("Test %d, expected error, got nil", i)
+			continue
+		}
+		if err != nil && tc.shouldErr {
+			continue
+		}
+		if got[0] != tc.expected {
+			t.Errorf("Test %d, expected %q, got %q", i, tc.expected, got[0])
+		}
+	}
+}
+
+func TestParseHostPort(t *testing.T) {
+	tests := []struct {
+		in        string
+		expected  string
+		shouldErr bool
+	}{
+		{"8.8.8.8:53", "8.8.8.8:53", false},
+		{"a.a.a.a:153", "", true},
+		{"8.8.8.8", "8.8.8.8:53", false},
+		{"8.8.8.8:", "8.8.8.8:53", false},
+		{"8.8.8.8::53", "", true},
+		{"resolv.conf", "", true},
+	}
+
+	for i, tc := range tests {
+		got, err := HostPort(tc.in, transport.Port)
+		if err == nil && tc.shouldErr {
+			t.Errorf("Test %d, expected error, got nil", i)
+			continue
+		}
+		if err != nil && !tc.shouldErr {
+			t.Errorf("Test %d, expected no error, got %q", i, err)
+		}
+		if got != tc.expected {
+			t.Errorf("Test %d, expected %q, got %q", i, tc.expected, got)
+		}
+	}
+}

plugin/pkg/parse/parse.go

@@ -4,7 +4,8 @@ package parse
 import (
 	"fmt"
 
-	"github.com/coredns/coredns/plugin/pkg/dnsutil"
+	"github.com/coredns/coredns/plugin/pkg/transport"
+
 	"github.com/mholt/caddy"
 )
 
@@ -19,7 +20,7 @@ func Transfer(c *caddy.Controller, secondary bool) (tos, froms []string, err err
 		tos = c.RemainingArgs()
 		for i := range tos {
 			if tos[i] != "*" {
-				normalized, err := dnsutil.ParseHostPort(tos[i], "53")
+				normalized, err := HostPort(tos[i], transport.Port)
 				if err != nil {
 					return nil, nil, err
 				}
@@ -34,7 +35,7 @@ func Transfer(c *caddy.Controller, secondary bool) (tos, froms []string, err err
 		froms = c.RemainingArgs()
 		for i := range froms {
 			if froms[i] != "*" {
-				normalized, err := dnsutil.ParseHostPort(froms[i], "53")
+				normalized, err := HostPort(froms[i], transport.Port)
 				if err != nil {
 					return nil, nil, err
 				}

plugin/pkg/parse/transport.go

@@ -0,0 +1,33 @@
+package parse
+
+import (
+	"strings"
+
+	"github.com/coredns/coredns/plugin/pkg/transport"
+)
+
+// Transport returns the transport defined in s and a string where the
+// transport prefix is removed (if there was any). If no transport is defined
+// we default to TransportDNS
+func Transport(s string) (trans string, addr string) {
+	switch {
+	case strings.HasPrefix(s, transport.TLS+"://"):
+		s = s[len(transport.TLS+"://"):]
+		return transport.TLS, s
+
+	case strings.HasPrefix(s, transport.DNS+"://"):
+		s = s[len(transport.DNS+"://"):]
+		return transport.DNS, s
+
+	case strings.HasPrefix(s, transport.GRPC+"://"):
+		s = s[len(transport.GRPC+"://"):]
+		return transport.GRPC, s
+
+	case strings.HasPrefix(s, transport.HTTPS+"://"):
+		s = s[len(transport.HTTPS+"://"):]
+
+		return transport.HTTPS, s
+	}
+
+	return transport.DNS, s
+}

plugin/pkg/parse/transport_test.go

@@ -0,0 +1,25 @@
+package parse
+
+import (
+	"testing"
+
+	"github.com/coredns/coredns/plugin/pkg/transport"
+)
+
+func TestTransport(t *testing.T) {
+	for i, test := range []struct {
+		input    string
+		expected string
+	}{
+		{"dns://.:53", transport.DNS},
+		{"2003::1/64.:53", transport.DNS},
+		{"grpc://example.org:1443 ", transport.GRPC},
+		{"tls://example.org ", transport.TLS},
+		{"https://example.org ", transport.HTTPS},
+	} {
+		actual, _ := Transport(test.input)
+		if actual != test.expected {
+			t.Errorf("Test %d: Expected %s but got %s", i, test.expected, actual)
+		}
+	}
+}