[confignet] Change Transport from string to TransportType

.chloggen/confignet-transport-type.yaml

@@ -0,0 +1,25 @@
+# Use this changelog template to create an entry for release notes.
+
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: breaking
+
+# The name of the component, or a single word describing the area of concern, (e.g. otlpreceiver)
+component: confignet
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Change `Transport` field from `string` to `TransportType`
+
+# One or more tracking issues or pull requests related to the change
+issues: [9385]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext:
+
+# Optional: The change log or logs in which this entry should be included.
+# e.g. '[user]' or '[user, api]'
+# Include 'user' if the change is relevant to end users.
+# Include 'api' if there is a change to a library API.
+# Default: '[user]'
+change_logs: [api]

config/configgrpc/configgrpc.go

@@ -285,7 +285,7 @@ func (gss *ServerConfig) ToServerContext(_ context.Context, host component.Host,
 
 func (gss *ServerConfig) toServerOption(host component.Host, settings component.TelemetrySettings) ([]grpc.ServerOption, error) {
 	switch gss.NetAddr.Transport {
-	case "tcp", "tcp4", "tcp6", "udp", "udp4", "udp6":
+	case confignet.TransportTypeTCP, confignet.TransportTypeTCP4, confignet.TransportTypeTCP6, confignet.TransportTypeUDP, confignet.TransportTypeUDP4, confignet.TransportTypeUDP6:
 		internal.WarnOnUnspecifiedHost(settings.Logger, gss.NetAddr.Endpoint)
 	}
 

config/configgrpc/configgrpc_test.go

@@ -194,7 +194,7 @@ func TestAllGrpcServerSettingsExceptAuth(t *testing.T) {
 	gss := &ServerConfig{
 		NetAddr: confignet.AddrConfig{
 			Endpoint:  "localhost:1234",
-			Transport: "tcp",
+			Transport: confignet.TransportTypeTCP,
 		},
 		TLSSetting: &configtls.ServerConfig{
 			TLSSetting:   configtls.Config{},
@@ -411,7 +411,7 @@ func TestGRPCServerWarning(t *testing.T) {
 			settings: ServerConfig{
 				NetAddr: confignet.AddrConfig{
 					Endpoint:  "0.0.0.0:1234",
-					Transport: "tcp",
+					Transport: confignet.TransportTypeTCP,
 				},
 			},
 			len: 1,
@@ -420,7 +420,7 @@ func TestGRPCServerWarning(t *testing.T) {
 			settings: ServerConfig{
 				NetAddr: confignet.AddrConfig{
 					Endpoint:  "127.0.0.1:1234",
-					Transport: "tcp",
+					Transport: confignet.TransportTypeTCP,
 				},
 			},
 			len: 0,
@@ -429,7 +429,7 @@ func TestGRPCServerWarning(t *testing.T) {
 			settings: ServerConfig{
 				NetAddr: confignet.AddrConfig{
 					Endpoint:  "0.0.0.0:1234",
-					Transport: "unix",
+					Transport: confignet.TransportTypeUnix,
 				},
 			},
 			len: 0,
@@ -462,7 +462,7 @@ func TestGRPCServerSettingsError(t *testing.T) {
 			settings: ServerConfig{
 				NetAddr: confignet.AddrConfig{
 					Endpoint:  "127.0.0.1:1234",
-					Transport: "tcp",
+					Transport: confignet.TransportTypeTCP,
 				},
 				TLSSetting: &configtls.ServerConfig{
 					TLSSetting: configtls.Config{
@@ -476,7 +476,7 @@ func TestGRPCServerSettingsError(t *testing.T) {
 			settings: ServerConfig{
 				NetAddr: confignet.AddrConfig{
 					Endpoint:  "127.0.0.1:1234",
-					Transport: "tcp",
+					Transport: confignet.TransportTypeTCP,
 				},
 				TLSSetting: &configtls.ServerConfig{
 					TLSSetting: configtls.Config{
@@ -490,7 +490,7 @@ func TestGRPCServerSettingsError(t *testing.T) {
 			settings: ServerConfig{
 				NetAddr: confignet.AddrConfig{
 					Endpoint:  "127.0.0.1:1234",
-					Transport: "tcp",
+					Transport: confignet.TransportTypeTCP,
 				},
 				TLSSetting: &configtls.ServerConfig{
 					ClientCAFile: "/doesnt/exist",
@@ -510,7 +510,7 @@ func TestGRPCServerSettings_ToListener_Error(t *testing.T) {
 	settings := ServerConfig{
 		NetAddr: confignet.AddrConfig{
 			Endpoint:  "127.0.0.1:1234567",
-			Transport: "tcp",
+			Transport: confignet.TransportTypeTCP,
 		},
 	}
 	_, err := settings.NetAddr.Listen(context.Background())
@@ -631,7 +631,7 @@ func TestHttpReception(t *testing.T) {
 			gss := &ServerConfig{
 				NetAddr: confignet.AddrConfig{
 					Endpoint:  "localhost:0",
-					Transport: "tcp",
+					Transport: confignet.TransportTypeTCP,
 				},
 				TLSSetting: test.tlsServerCreds,
 			}
@@ -679,7 +679,7 @@ func TestReceiveOnUnixDomainSocket(t *testing.T) {
 	gss := &ServerConfig{
 		NetAddr: confignet.AddrConfig{
 			Endpoint:  socketName,
-			Transport: "unix",
+			Transport: confignet.TransportTypeUnix,
 		},
 	}
 	ln, err := gss.NetAddr.Listen(context.Background())
@@ -875,7 +875,7 @@ func TestClientInfoInterceptors(t *testing.T) {
 				gss := &ServerConfig{
 					NetAddr: confignet.AddrConfig{
 						Endpoint:  "localhost:0",
-						Transport: "tcp",
+						Transport: confignet.TransportTypeTCP,
 					},
 				}
 				srv, err := gss.ToServerContext(context.Background(), componenttest.NewNopHost(), componenttest.NewNopTelemetrySettings())

config/confignet/confignet.go

@@ -5,10 +5,56 @@ package confignet // import "go.opentelemetry.io/collector/config/confignet"
 
 import (
 	"context"
+	"fmt"
 	"net"
 	"time"
 )
 
+// TransportType represents a type of network transport protocol
+type TransportType string
+
+const (
+	TransportTypeTCP        TransportType = "tcp"
+	TransportTypeTCP4       TransportType = "tcp4"
+	TransportTypeTCP6       TransportType = "tcp6"
+	TransportTypeUDP        TransportType = "udp"
+	TransportTypeUDP4       TransportType = "udp4"
+	TransportTypeUDP6       TransportType = "udp6"
+	TransportTypeIP         TransportType = "ip"
+	TransportTypeIP4        TransportType = "ip4"
+	TransportTypeIP6        TransportType = "ip6"
+	TransportTypeUnix       TransportType = "unix"
+	TransportTypeUnixgram   TransportType = "unixgram"
+	TransportTypeUnixPacket TransportType = "unixpacket"
+	transportTypeEmpty      TransportType = ""
+)
+
+// UnmarshalText unmarshalls text to a TransportType.
+// Valid values are "tcp", "tcp4", "tcp6", "udp", "udp4",
+// "udp6", "ip", "ip4", "ip6", "unix", "unixgram" and "unixpacket"
+func (tt *TransportType) UnmarshalText(in []byte) error {
+	typ := TransportType(in)
+	switch typ {
+	case TransportTypeTCP,
+		TransportTypeTCP4,
+		TransportTypeTCP6,
+		TransportTypeUDP,
+		TransportTypeUDP4,
+		TransportTypeUDP6,
+		TransportTypeIP,
+		TransportTypeIP4,
+		TransportTypeIP6,
+		TransportTypeUnix,
+		TransportTypeUnixgram,
+		TransportTypeUnixPacket,
+		transportTypeEmpty:
+		*tt = typ
+		return nil
+	default:
+		return fmt.Errorf("unsupported transport type %q", typ)
+	}
+}
+
 // DialerConfig contains options for connecting to an address.
 type DialerConfig struct {
 	// Timeout is the maximum amount of time a dial will wait for
@@ -25,9 +71,9 @@ type AddrConfig struct {
 	// "[fe80::1%zone]:80". The zone specifies the scope of the literal IPv6 address as defined in RFC 4007.
 	Endpoint string `mapstructure:"endpoint"`
 
-	// Transport to use. Known protocols are "tcp", "tcp4" (IPv4-only), "tcp6" (IPv6-only), "udp", "udp4" (IPv4-only),
+	// Transport to use. Allowed protocols are "tcp", "tcp4" (IPv4-only), "tcp6" (IPv6-only), "udp", "udp4" (IPv4-only),
 	// "udp6" (IPv6-only), "ip", "ip4" (IPv4-only), "ip6" (IPv6-only), "unix", "unixgram" and "unixpacket".
-	Transport string `mapstructure:"transport"`
+	Transport TransportType `mapstructure:"transport"`
 
 	// DialerConfig contains options for connecting to an address.
 	DialerConfig DialerConfig `mapstructure:"dialer"`
@@ -36,13 +82,33 @@ type AddrConfig struct {
 // Dial equivalent with net.Dialer's DialContext for this address.
 func (na *AddrConfig) Dial(ctx context.Context) (net.Conn, error) {
 	d := net.Dialer{Timeout: na.DialerConfig.Timeout}
-	return d.DialContext(ctx, na.Transport, na.Endpoint)
+	return d.DialContext(ctx, string(na.Transport), na.Endpoint)
 }
 
 // Listen equivalent with net.ListenConfig's Listen for this address.
 func (na *AddrConfig) Listen(ctx context.Context) (net.Listener, error) {
 	lc := net.ListenConfig{}
-	return lc.Listen(ctx, na.Transport, na.Endpoint)
+	return lc.Listen(ctx, string(na.Transport), na.Endpoint)
+}
+
+func (na *AddrConfig) Validate() error {
+	switch na.Transport {
+	case TransportTypeTCP,
+		TransportTypeTCP4,
+		TransportTypeTCP6,
+		TransportTypeUDP,
+		TransportTypeUDP4,
+		TransportTypeUDP6,
+		TransportTypeIP,
+		TransportTypeIP4,
+		TransportTypeIP6,
+		TransportTypeUnix,
+		TransportTypeUnixgram,
+		TransportTypeUnixPacket:
+		return nil
+	default:
+		return fmt.Errorf("invalid transport type %q", na.Transport)
+	}
 }
 
 // TCPAddrConfig represents a TCP endpoint address.
@@ -61,11 +127,11 @@ type TCPAddrConfig struct {
 // Dial equivalent with net.Dialer's DialContext for this address.
 func (na *TCPAddrConfig) Dial(ctx context.Context) (net.Conn, error) {
 	d := net.Dialer{Timeout: na.DialerConfig.Timeout}
-	return d.DialContext(ctx, "tcp", na.Endpoint)
+	return d.DialContext(ctx, string(TransportTypeTCP), na.Endpoint)
 }
 
 // Listen equivalent with net.ListenConfig's Listen for this address.
 func (na *TCPAddrConfig) Listen(ctx context.Context) (net.Listener, error) {
 	lc := net.ListenConfig{}
-	return lc.Listen(ctx, "tcp", na.Endpoint)
+	return lc.Listen(ctx, string(TransportTypeTCP), na.Endpoint)
 }

config/confignet/confignet_test.go

@@ -11,12 +11,13 @@ import (
 	"time"
 
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 )
 
 func TestAddrConfigTimeout(t *testing.T) {
 	nac := &AddrConfig{
 		Endpoint:  "localhost:0",
-		Transport: "tcp",
+		Transport: TransportTypeTCP,
 		DialerConfig: DialerConfig{
 			Timeout: -1 * time.Second,
 		},
@@ -51,7 +52,7 @@ func TestTCPAddrConfigTimeout(t *testing.T) {
 func TestAddrConfig(t *testing.T) {
 	nas := &AddrConfig{
 		Endpoint:  "localhost:0",
-		Transport: "tcp",
+		Transport: TransportTypeTCP,
 	}
 	ln, err := nas.Listen(context.Background())
 	assert.NoError(t, err)
@@ -71,7 +72,7 @@ func TestAddrConfig(t *testing.T) {
 
 	nac := &AddrConfig{
 		Endpoint:  ln.Addr().String(),
-		Transport: "tcp",
+		Transport: TransportTypeTCP,
 	}
 	var conn net.Conn
 	conn, err = nac.Dial(context.Background())
@@ -83,6 +84,23 @@ func TestAddrConfig(t *testing.T) {
 	assert.NoError(t, ln.Close())
 }
 
+func Test_NetAddr_Validate(t *testing.T) {
+	na := &AddrConfig{
+		Transport: TransportTypeTCP,
+	}
+	assert.NoError(t, na.Validate())
+
+	na = &AddrConfig{
+		Transport: transportTypeEmpty,
+	}
+	assert.Error(t, na.Validate())
+
+	na = &AddrConfig{
+		Transport: "random string",
+	}
+	assert.Error(t, na.Validate())
+}
+
 func TestTCPAddrConfig(t *testing.T) {
 	nas := &TCPAddrConfig{
 		Endpoint: "localhost:0",
@@ -115,3 +133,11 @@ func TestTCPAddrConfig(t *testing.T) {
 	<-done
 	assert.NoError(t, ln.Close())
 }
+
+func Test_TransportType_UnmarshalText(t *testing.T) {
+	var tt TransportType
+	err := tt.UnmarshalText([]byte("tcp"))
+	require.NoError(t, err)
+	err = tt.UnmarshalText([]byte("invalid"))
+	require.Error(t, err)
+}

receiver/otlpreceiver/config_test.go

@@ -89,7 +89,7 @@ func TestUnmarshalConfig(t *testing.T) {
 				GRPC: &configgrpc.ServerConfig{
 					NetAddr: confignet.AddrConfig{
 						Endpoint:  "0.0.0.0:4317",
-						Transport: "tcp",
+						Transport: confignet.TransportTypeTCP,
 					},
 					TLSSetting: &configtls.ServerConfig{
 						TLSSetting: configtls.Config{
@@ -150,7 +150,7 @@ func TestUnmarshalConfigUnix(t *testing.T) {
 				GRPC: &configgrpc.ServerConfig{
 					NetAddr: confignet.AddrConfig{
 						Endpoint:  "/tmp/grpc_otlp.sock",
-						Transport: "unix",
+						Transport: confignet.TransportTypeUnix,
 					},
 					ReadBufferSize: 512 * 1024,
 				},

receiver/otlpreceiver/factory.go

@@ -44,7 +44,7 @@ func createDefaultConfig() component.Config {
 			GRPC: &configgrpc.ServerConfig{
 				NetAddr: confignet.AddrConfig{
 					Endpoint:  localhostgate.EndpointForPort(grpcPort),
-					Transport: "tcp",
+					Transport: confignet.TransportTypeTCP,
 				},
 				// We almost write 0 bytes, so no need to tune WriteBufferSize.
 				ReadBufferSize: 512 * 1024,