Code to parse socket addresses

tools/utils/sockets.go

@@ -0,0 +1,46 @@
+package utils
+
+import (
+	"fmt"
+	"github.com/seancfoley/ipaddress-go/ipaddr"
+	"runtime"
+	"strings"
+)
+
+func Cut(s string, sep string) (string, string, bool) {
+	if i := strings.Index(s, sep); i >= 0 {
+		return s[:i], s[i+len(sep):], true
+	}
+	return s, "", false
+}
+
+func ParseSocketAddress(spec string) (network string, addr string, err error) {
+	network, addr, found := Cut(spec, ":")
+	if !found {
+		err = fmt.Errorf("Invalid socket address: %s", spec)
+		return
+	}
+	if network == "unix" {
+		if strings.HasSuffix(addr, "@") && runtime.GOOS != "linux" {
+			err = fmt.Errorf("Abstract UNIX sockets are only supported on Linux. Cannot use: %s", spec)
+		}
+		return
+	}
+
+	if network == "tcp" || network == "tcp6" || network == "tcp4" {
+		host := ipaddr.NewHostName(addr)
+		if host.IsAddress() {
+			network = "ip"
+		}
+		return
+	}
+	if network == "ip" || network == "ip6" || network == "ip4" {
+		host := ipaddr.NewHostName(addr)
+		if !host.IsAddress() {
+			err = fmt.Errorf("Not a valid IP address: %#v. Cannot use: %s", addr, spec)
+		}
+		return
+	}
+	err = fmt.Errorf("Unknown network type: %#v in socket address: %s", network, spec)
+	return
+}

tools/utils/sockets_test.go

@@ -0,0 +1,57 @@
+package utils
+
+import (
+	"fmt"
+	"runtime"
+	"testing"
+)
+
+func TestParseSocketAddress(t *testing.T) {
+	en := "unix"
+	ea := "/tmp/test"
+	var eerr error = nil
+
+	test := func(spec string) {
+		n, a, err := ParseSocketAddress(spec)
+		if err != eerr {
+			if eerr == nil {
+				t.Fatalf("Parsing of %s failed with unexpected error: %s", spec, err)
+			}
+			if err == nil {
+				t.Fatalf("Parsing of %s did not fail, unexpectedly", spec)
+			}
+			return
+		}
+		if a != ea {
+			t.Fatalf("actual != expected, %s != %s, when parsing %s", a, ea, spec)
+		}
+		if n != en {
+			t.Fatalf("actual != expected, %s != %s, when parsing %s", n, en, spec)
+		}
+	}
+
+	testf := func(spec string, netw string, addr string) {
+		eerr = nil
+		en = netw
+		ea = addr
+		test(spec)
+	}
+	teste := func(spec string, e string) {
+		eerr = fmt.Errorf(e)
+		test(spec)
+	}
+
+	test("unix:/tmp/test")
+	if runtime.GOOS == "linux" {
+		ea = "@test"
+	} else {
+		eerr = fmt.Errorf("bad kitty")
+	}
+	test("unix:@test")
+	testf("tcp:localhost:123", "tcp", "localhost:123")
+	testf("tcp:1.1.1.1:123", "ip", "1.1.1.1:123")
+	testf("tcp:fe80::1", "ip", "fe80::1")
+	teste("xxx", "bad kitty")
+	teste("xxx:yyy", "bad kitty")
+	teste(":yyy", "bad kitty")
+}