Remote tap extension rework

extension/remotetapextension/README.md

@@ -6,14 +6,12 @@
 | Stability     | [development]  |
 | Distributions | [] |
 | Issues        | [![Open issues](https://img.shields.io/github/issues-search/open-telemetry/opentelemetry-collector-contrib?query=is%3Aissue%20is%3Aopen%20label%3Aextension%2Fremotetap%20&label=open&color=orange&logo=opentelemetry)](https://github.com/open-telemetry/opentelemetry-collector-contrib/issues?q=is%3Aopen+is%3Aissue+label%3Aextension%2Fremotetap) [![Closed issues](https://img.shields.io/github/issues-search/open-telemetry/opentelemetry-collector-contrib?query=is%3Aissue%20is%3Aclosed%20label%3Aextension%2Fremotetap%20&label=closed&color=blue&logo=opentelemetry)](https://github.com/open-telemetry/opentelemetry-collector-contrib/issues?q=is%3Aclosed+is%3Aissue+label%3Aextension%2Fremotetap) |
-| [Code Owners](https://github.com/open-telemetry/opentelemetry-collector-contrib/blob/main/CONTRIBUTING.md#becoming-a-code-owner)    | [@atoulme](https://www.github.com/atoulme) |
+| [Code Owners](https://github.com/open-telemetry/opentelemetry-collector-contrib/blob/main/CONTRIBUTING.md#becoming-a-code-owner)    | [@atoulme](https://www.github.com/atoulme), [@wildum](https://www.github.com/wildum) |
 
 [development]: https://github.com/open-telemetry/opentelemetry-collector#development
 <!-- end autogenerated section -->
 
-This extension runs as a Web server that loads the remote observers that are registered against it.
-
-It allows users of the collectors to visualize data going through pipelines.
+This extension runs as a Web server and allows users to visualize data going through pipelines.
 
 The following settings are required:
 

extension/remotetapextension/config.go

@@ -4,18 +4,21 @@
 package remotetapextension // import "github.com/open-telemetry/opentelemetry-collector-contrib/extension/remotetapextension"
 
 import (
+	"github.com/open-telemetry/opentelemetry-collector-contrib/internal/common/localhostgate"
 	"go.opentelemetry.io/collector/component"
 	"go.opentelemetry.io/collector/config/confighttp"
 )
 
+type CallbackID string
+
 type Config struct {
 	confighttp.ServerConfig `mapstructure:",squash"` // squash ensures fields are correctly decoded in embedded struct
 }
 
 func createDefaultConfig() component.Config {
 	return &Config{
 		ServerConfig: confighttp.ServerConfig{
-			Endpoint: "127.0.0.1:11000",
+			Endpoint: localhostgate.EndpointForPort(11000),
 		},
 	}
 }

extension/remotetapextension/extension.go

@@ -6,47 +6,76 @@ package remotetapextension // import "github.com/open-telemetry/opentelemetry-co
 import (
 	"context"
 	"embed"
-	"errors"
+	"fmt"
 	"io/fs"
 	"net/http"
 
 	"go.opentelemetry.io/collector/component"
-	"go.opentelemetry.io/collector/component/componentstatus"
 	"go.opentelemetry.io/collector/extension"
+	"go.opentelemetry.io/collector/pdata/plog"
+	"go.opentelemetry.io/collector/pdata/pmetric"
+	"go.opentelemetry.io/collector/pdata/ptrace"
 )
 
 //go:embed http/*
 var httpFS embed.FS
 
-type remoteObserverExtension struct {
+type remoteTapExtension struct {
 	config   *Config
 	settings extension.Settings
 	server   *http.Server
 }
 
-func (s *remoteObserverExtension) Start(ctx context.Context, host component.Host) error {
+type ComponentID string
 
+// TODO: the extension should implement this interface when available in core
+// var _ pdata.Publisher = &remoteTapExtension{}
+
+func (s *remoteTapExtension) Start(ctx context.Context, host component.Host) error {
 	htmlContent, err := fs.Sub(httpFS, "html")
 	if err != nil {
 		return err
 	}
 	mux := http.NewServeMux()
 	mux.Handle("/", http.FileServer(http.FS(htmlContent)))
+
+	ln, err := s.config.ServerConfig.ToListener(ctx)
+	if err != nil {
+		return fmt.Errorf("failed to bind to address %s: %w", s.config.Endpoint, err)
+	}
+
 	s.server, err = s.config.ServerConfig.ToServer(ctx, host, s.settings.TelemetrySettings, mux)
 	if err != nil {
 		return err
 	}
 
 	go func() {
-		err := s.server.ListenAndServe()
-		if err != nil && !errors.Is(err, http.ErrServerClosed) {
-			componentstatus.ReportStatus(host, componentstatus.NewFatalErrorEvent(err))
-		}
+		s.server.Serve(ln)
 	}()
 	return nil
 }
 
-func (s *remoteObserverExtension) Shutdown(_ context.Context) error {
+// IsActive returns true when at least one connection is open for the given componentID.
+func (s *remoteTapExtension) IsActive(componentID ComponentID) bool {
+	return false
+}
+
+// PublishMetrics sends metrics for a given componentID.
+func (s *remoteTapExtension) PublishMetrics(componentID ComponentID, md pmetric.Metrics) {
+	// TODO: do something with the metrics
+}
+
+// PublishTraces sends traces for a given componentID.
+func (s *remoteTapExtension) PublishTraces(componentID ComponentID, td ptrace.Traces) {
+	// TODO: do something with the traces
+}
+
+// PublishLogs sends logs for a given componentID.
+func (s *remoteTapExtension) PublishLogs(componentID ComponentID, ld plog.Logs) {
+	// TODO: do something with the logs
+}
+
+func (s *remoteTapExtension) Shutdown(_ context.Context) error {
 	if s.server == nil {
 		return nil
 	}

extension/remotetapextension/factory.go

@@ -22,5 +22,5 @@ func NewFactory() extension.Factory {
 }
 
 func createExtension(_ context.Context, settings extension.Settings, config component.Config) (extension.Extension, error) {
-	return &remoteObserverExtension{config: config.(*Config), settings: settings}, nil
+	return &remoteTapExtension{config: config.(*Config), settings: settings}, nil
 }

extension/remotetapextension/go.mod

@@ -3,12 +3,13 @@ module github.com/open-telemetry/opentelemetry-collector-contrib/extension/remot
 go 1.22.0
 
 require (
+	github.com/open-telemetry/opentelemetry-collector-contrib/internal/common v0.107.0
 	github.com/stretchr/testify v1.9.0
 	go.opentelemetry.io/collector/component v0.107.1-0.20240827012220-5963d446ca4a
-	go.opentelemetry.io/collector/component/componentstatus v0.107.1-0.20240827012220-5963d446ca4a
 	go.opentelemetry.io/collector/config/confighttp v0.107.1-0.20240827012220-5963d446ca4a
 	go.opentelemetry.io/collector/confmap v0.107.1-0.20240827012220-5963d446ca4a
 	go.opentelemetry.io/collector/extension v0.107.1-0.20240827012220-5963d446ca4a
+	go.opentelemetry.io/collector/pdata v1.13.1-0.20240827012220-5963d446ca4a
 	go.uber.org/goleak v1.3.0
 )
 
@@ -25,12 +26,15 @@ require (
 	github.com/golang/snappy v0.0.4 // indirect
 	github.com/google/uuid v1.6.0 // indirect
 	github.com/hashicorp/go-version v1.7.0 // indirect
+	github.com/json-iterator/go v1.1.12 // indirect
 	github.com/klauspost/compress v1.17.9 // indirect
 	github.com/knadh/koanf/maps v0.1.1 // indirect
 	github.com/knadh/koanf/providers/confmap v0.1.0 // indirect
 	github.com/knadh/koanf/v2 v2.1.1 // indirect
 	github.com/mitchellh/copystructure v1.2.0 // indirect
 	github.com/mitchellh/reflectwalk v1.0.2 // indirect
+	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
+	github.com/modern-go/reflect2 v1.0.2 // indirect
 	github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
 	github.com/prometheus/client_golang v1.20.1 // indirect
@@ -40,6 +44,7 @@ require (
 	github.com/rs/cors v1.11.0 // indirect
 	go.opentelemetry.io/collector v0.107.1-0.20240827012220-5963d446ca4a // indirect
 	go.opentelemetry.io/collector/client v1.13.1-0.20240827012220-5963d446ca4a // indirect
+	go.opentelemetry.io/collector/component/componentstatus v0.107.1-0.20240827012220-5963d446ca4a // indirect
 	go.opentelemetry.io/collector/config/configauth v0.107.1-0.20240827012220-5963d446ca4a // indirect
 	go.opentelemetry.io/collector/config/configcompression v1.13.1-0.20240827012220-5963d446ca4a // indirect
 	go.opentelemetry.io/collector/config/configopaque v1.13.1-0.20240827012220-5963d446ca4a // indirect
@@ -48,7 +53,6 @@ require (
 	go.opentelemetry.io/collector/config/internal v0.107.1-0.20240827012220-5963d446ca4a // indirect
 	go.opentelemetry.io/collector/extension/auth v0.107.1-0.20240827012220-5963d446ca4a // indirect
 	go.opentelemetry.io/collector/featuregate v1.13.1-0.20240827012220-5963d446ca4a // indirect
-	go.opentelemetry.io/collector/pdata v1.13.1-0.20240827012220-5963d446ca4a // indirect
 	go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.53.0 // indirect
 	go.opentelemetry.io/otel v1.28.0 // indirect
 	go.opentelemetry.io/otel/exporters/prometheus v0.50.0 // indirect

extension/remotetapextension/metadata.yaml

@@ -6,7 +6,7 @@ status:
     development: [extension]
   distributions: []
   codeowners:
-    active: [atoulme]
+    active: [atoulme, wildum]
 
 tests:
   config: