expose grpc(default) when using otelarrow as exporter

.chloggen/expose_grpc_otelarrow.yaml

@@ -0,0 +1,17 @@
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: enhancement
+
+# The name of the component, or a single word describing the area of concern, (e.g. collector, target allocator, auto-instrumentation, opamp, github action)
+component: collector
+
+# A brief description of the change. Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: "Expose the default gRPC receiver port (4317) for otelarrow and automatically apply grpc protocol defaults when protocols are omitted or otelarrow is enabled."
+
+
+# One or more tracking issues related to the change
+issues: [4713]
+
+# (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:

apis/v1beta1/config.go

@@ -355,9 +355,71 @@ func (c *Config) GetAllRbacRules(logger logr.Logger) ([]rbacv1.PolicyRule, error
 // ApplyDefaults applies default configuration values to the collector config.
 // Optional DefaultsOption arguments can be provided to customize behavior.
 func (c *Config) ApplyDefaults(logger logr.Logger, opts ...components.DefaultOption) ([]EventInfo, error) {
+	c.ensureOtelarrowGrpcDefaults(opts...)
 	return c.applyDefaultForComponentKinds(logger, opts, KindReceiver, KindExporter, KindExtension)
 }
 
+func (c *Config) ensureOtelarrowGrpcDefaults(opts ...components.DefaultOption) {
+	if c == nil {
+		return
+	}
+
+	defaultCfg := &components.DefaultConfig{}
+	for _, opt := range opts {
+		if opt != nil {
+			opt(defaultCfg)
+		}
+	}
+
+	enabledReceivers := c.GetEnabledComponents()[KindReceiver]
+	if len(enabledReceivers) == 0 {
+		return
+	}
+
+	if c.Receivers.Object == nil {
+		c.Receivers.Object = map[string]any{}
+	}
+
+	for receiverName := range enabledReceivers {
+		if components.ComponentType(receiverName) != "otelarrow" {
+			continue
+		}
+
+		receiverCfg, ok := c.Receivers.Object[receiverName]
+		if !ok || receiverCfg == nil {
+			c.Receivers.Object[receiverName] = map[string]any{
+				"protocols": map[string]any{
+					components.GrpcProtocol: map[string]any{},
+				},
+			}
+			continue
+		}
+
+		receiverCfgMap, ok := receiverCfg.(map[string]any)
+		if !ok {
+			continue
+		}
+
+		protocolsValue, ok := receiverCfgMap["protocols"]
+		if !ok || protocolsValue == nil {
+			receiverCfgMap["protocols"] = map[string]any{
+				components.GrpcProtocol: map[string]any{},
+			}
+			c.Receivers.Object[receiverName] = receiverCfgMap
+			continue
+		}
+
+		protocols, ok := protocolsValue.(map[string]any)
+		if !ok || len(protocols) != 0 {
+			continue
+		}
+
+		protocols[components.GrpcProtocol] = map[string]any{}
+		receiverCfgMap["protocols"] = protocols
+		c.Receivers.Object[receiverName] = receiverCfgMap
+	}
+}
+
 // GetLivenessProbe gets the first enabled liveness probe. There should only ever be one extension enabled
 // that provides the hinting for the liveness probe.
 func (c *Config) GetLivenessProbe(logger logr.Logger) (*corev1.Probe, error) {

apis/v1beta1/config_test.go

@@ -732,10 +732,11 @@ func TestConfig_getEnvironmentVariablesForComponentKinds(t *testing.T) {
 
 func TestConfig_GetReceiverPorts(t *testing.T) {
 	tests := []struct {
-		name    string
-		file    string
-		want    []v1.ServicePort
-		wantErr bool
+		name          string
+		file          string
+		want          []v1.ServicePort
+		wantErr       bool
+		applyDefaults bool
 	}{
 		{
 			name: "k8sevents",
@@ -788,6 +789,33 @@ func TestConfig_GetReceiverPorts(t *testing.T) {
 				},
 			},
 		},
+		{
+			name: "otelarrow",
+			file: "testdata/otelcol-otelarrow.yaml",
+			want: []v1.ServicePort{
+				{
+					Name:        "otelarrow-grpc",
+					Protocol:    "",
+					AppProtocol: ptr.To("grpc"),
+					Port:        4317,
+					TargetPort:  intstr.FromInt32(4317),
+				},
+			},
+		},
+		{
+			name:          "otelarrow missing protocols",
+			file:          "testdata/otelcol-otelarrow-no-protocols.yaml",
+			applyDefaults: true,
+			want: []v1.ServicePort{
+				{
+					Name:        "otelarrow-grpc",
+					Protocol:    "",
+					AppProtocol: ptr.To("grpc"),
+					Port:        4317,
+					TargetPort:  intstr.FromInt32(4317),
+				},
+			},
+		},
 		{
 			name: "filelog",
 			file: "testdata/otelcol-filelog.yaml",
@@ -807,6 +835,10 @@ func TestConfig_GetReceiverPorts(t *testing.T) {
 			c := &Config{}
 			err = go_yaml.Unmarshal(collectorYaml, c)
 			require.NoError(t, err)
+			if tt.applyDefaults {
+				_, err = c.ApplyDefaults(logr.Discard())
+				require.NoError(t, err)
+			}
 			ports, err := c.GetReceiverPorts(logr.Discard())
 			if tt.wantErr {
 				require.Error(t, err)

apis/v1beta1/testdata/otelcol-otelarrow-no-protocols.yaml

@@ -0,0 +1,11 @@
+receivers:
+  otelarrow: {}
+
+exporters:
+  debug:
+
+service:
+  pipelines:
+    traces:
+      receivers: [otelarrow]
+      exporters: [debug]

apis/v1beta1/testdata/otelcol-otelarrow.yaml

@@ -0,0 +1,13 @@
+receivers:
+  otelarrow:
+    protocols:
+      grpc:
+
+exporters:
+  debug:
+
+service:
+  pipelines:
+    traces:
+      receivers: [otelarrow]
+      exporters: [debug]

internal/components/receivers/helpers.go

@@ -32,6 +32,11 @@ func ReceiverFor(name string) components.Parser {
 }
 
 var componentParsers = []components.Parser{
+	components.NewMultiPortReceiverBuilder("otelarrow").
+		AddPortMapping(components.NewProtocolBuilder("grpc", 4317).
+			WithAppProtocol(&components.GrpcProtocol).
+			WithTargetPort(4317)).
+		MustBuild(),
 	components.NewMultiPortReceiverBuilder("otlp").
 		AddPortMapping(components.NewProtocolBuilder("grpc", 4317).
 			WithAppProtocol(&components.GrpcProtocol).