Merge pull request #108 from wleese/sd_endpoint

allow setting the service discovery endpoint

README.md

@@ -244,6 +244,7 @@ The `interfaces` parameter allows for one or more specifications to be used when
 - `fdc6:238c:c4bc::/48` : Match the first IP that is contained within the IPv6 Network
 - `inet` : Match the first IPv4 Address (excluding `127.0.0.0/8`)
 - `inet6` : Match the first IPv6 Address (excluding `::1/128`)
+- `static: 192.168.1.100` : Use this Address. Useful for all cases where the IP is not visible in the container
 
 Interfaces and their IP addresses are ordered alphabetically by interface name, then by IP address (lexicographically by bytes).
 

utils/ips.go

@@ -88,6 +88,11 @@ func GetIP(specList []string) (string, error) {
 func findIPWithSpecs(specs []interfaceSpec, interfaceIPs []interfaceIP) (string, error) {
 	// Find the interface matching the name given
 	for _, spec := range specs {
+		// Static IP given
+		origSpec, ok := spec.(staticInterfaceSpec)
+		if ok {
+			return origSpec.IP.String(), nil
+		}
 		index := 0
 		iface := ""
 		for _, iip := range interfaceIPs {
@@ -122,6 +127,18 @@ type inetInterfaceSpec struct {
 	IPv6 bool
 }
 
+// -- matches static
+type staticInterfaceSpec struct {
+	Spec string
+	Name string
+	IP net.IP
+}
+
+func (s staticInterfaceSpec) Match(index int, iip interfaceIP) bool {
+	// Never matches
+	return false
+}
+
 func (s inetInterfaceSpec) Match(index int, iip interfaceIP) bool {
 	if s.Name != "*" && s.Name != iip.Name {
 		return false
@@ -187,6 +204,16 @@ func parseInterfaceSpec(spec string) (interfaceSpec, error) {
 	if spec == "inet6" {
 		return inetInterfaceSpec{Spec: spec, Name: "*", IPv6: true}, nil
 	}
+	if strings.HasPrefix(spec, "static:") {
+		ip := strings.SplitAfter(spec, "static:")
+		if _, err := strconv.Atoi(ip[1]); err != nil {
+			nip := net.ParseIP(ip[1])
+			if nip == nil {
+				return nil, fmt.Errorf("Unable to parse static ip %s in %s", ip[0], spec)
+			}
+			return staticInterfaceSpec{Spec: spec, Name: "static", IP: nip}, nil
+		}
+	}
 
 	if match := ifaceSpec.FindStringSubmatch(spec); match != nil {
 		name := match[1]

utils/ips_test.go

@@ -43,6 +43,9 @@ func TestGetIp(t *testing.T) {
 	if ip, err := GetIP([]string{"interface-does-not-exist"}); err == nil {
 		t.Errorf("Expected interface not found, but instead got an IP: %s", ip)
 	}
+	if ip, _ := GetIP([]string{"static:192.168.1.100", "lo"}); ip != "192.168.1.100" {
+		t.Errorf("Expected to find static ip 192.168.1.100, but found: %s", ip)
+	}
 }
 
 func TestInterfaceIpsLoopback(t *testing.T) {
@@ -125,11 +128,12 @@ func TestInterfaceIpsError(t *testing.T) {
 
 func TestInterfaceSpecParse(t *testing.T) {
 	// Test Error Cases
-	testSpecError(t, "")           // Nothing
-	testSpecError(t, "!")          // Nonsense
-	testSpecError(t, "127.0.0.1")  // No Network
-	testSpecError(t, "eth0:inet5") // Invalid IP Version
-	testSpecError(t, "eth0[-1]")   // Invalid Index
+	testSpecError(t, "")              // Nothing
+	testSpecError(t, "!")             // Nonsense
+	testSpecError(t, "127.0.0.1")     // No Network
+	testSpecError(t, "eth0:inet5")    // Invalid IP Version
+	testSpecError(t, "eth0[-1]")      // Invalid Index
+	testSpecError(t, "static:abcdef") // Invalid IP
 
 	// Test Interface Case
 	testSpecInterfaceName(t, "eth0", "eth0", false, -1)
@@ -138,6 +142,7 @@ func TestInterfaceSpecParse(t *testing.T) {
 	testSpecInterfaceName(t, "eth0[2]", "eth0", false, 2)
 	testSpecInterfaceName(t, "inet", "*", false, -1)
 	testSpecInterfaceName(t, "inet6", "*", true, -1)
+	testSpecInterfaceName(t, "static:192.168.1.100", "static", false, 1)
 
 	// Test CIDR Case
 	testSpecCIDR(t, "10.0.0.0/16")
@@ -155,6 +160,17 @@ func testSpecInterfaceName(t *testing.T, specStr string, name string, ipv6 bool,
 	if err != nil {
 		t.Errorf("Expected parse to succeed, but got error: %s", err)
 	}
+	if name == "static" {
+		staticSpec, ok := spec.(staticInterfaceSpec)
+		if !ok {
+			t.Errorf("Expected %s to parse as staticInterfaceSpec", spec)
+			return
+		}
+		if staticSpec.Name != "static" {
+			t.Errorf("Expected to parse interface name static but got %s", staticSpec.Name)
+		}
+		return
+	}
 	if index < 0 {
 		inetSpec, ok := spec.(inetInterfaceSpec)
 		if !ok {
@@ -208,6 +224,9 @@ func TestFindIPWithSpecs(t *testing.T) {
 	testIPSpec(t, iips, "127.0.0.1", "lo")
 	testIPSpec(t, iips, "::1", "lo:inet6")
 
+	// Static
+	testIPSpec(t, iips, "192.168.1.100", "static:192.168.1.100")
+
 	// Interface Name
 	testIPSpec(t, iips, "10.2.0.1", "eth0")
 	testIPSpec(t, iips, "10.2.0.1", "eth0:inet")
@@ -300,6 +319,7 @@ func getTestIPs() []interfaceIP {
 		newInterfaceIP("eth2", "fdc6:238c:c4bc::1"),
 		newInterfaceIP("lo", "::1"),
 		newInterfaceIP("lo", "127.0.0.1"),
+		newInterfaceIP("static:192.168.1.100", "192.168.1.100"),
 	}
 }