Add optional in-VM OTLP telemetry export sink

server/cmd/api/main.go

@@ -125,6 +125,29 @@ func main() {
 		}
 	}
 
+	// Optional OTLP export sink. Independent of S2; both can run together.
+	var otlpWriter *events.OTLPStorageWriter
+	if config.OTLPEndpoint != "" {
+		headers := map[string]string{}
+		if config.OTLPInstanceJWT != "" {
+			headers["Authorization"] = "Bearer " + config.OTLPInstanceJWT
+		}
+		slogger.Info("OTLP export enabled", "endpoint", config.OTLPEndpoint, "path", config.OTLPPath)
+		otlpWriter = events.NewOTLPStorageWriter(eventStream, events.OTLPConfig{
+			Endpoint:     config.OTLPEndpoint,
+			URLPath:      config.OTLPPath,
+			Insecure:     config.OTLPInsecure,
+			Headers:      headers,
+			ServiceName:  config.OTLPServiceName,
+			InstanceName: config.OTLPInstanceName,
+			Metro:        config.OTLPMetro,
+		}, slogger)
+		if err := otlpWriter.Start(ctx); err != nil {
+			slogger.Error("failed to start OTLP storage writer", "err", err)
+			os.Exit(1)
+		}
+	}
+
 	apiService, err := api.New(
 		recorder.NewFFmpegManager(),
 		recorder.NewFFmpegRecorderFactory(config.PathToFFmpeg, defaultParams, stz),
@@ -306,6 +329,14 @@ func main() {
 			slogger.Error("s2 storage writer stop failed", "err", err)
 		}
 	}
+
+	if otlpWriter != nil {
+		stopCtx, stopCancel := context.WithTimeout(context.Background(), 10*time.Second)
+		defer stopCancel()
+		if err := otlpWriter.Stop(stopCtx); err != nil {
+			slogger.Error("otlp storage writer stop failed", "err", err)
+		}
+	}
 }
 
 func mustFFmpeg() {

server/cmd/config/config.go

@@ -47,6 +47,17 @@ type Config struct {
 	S2Basin       string `envconfig:"S2_BASIN"        default:""`
 	S2AccessToken string `envconfig:"S2_ACCESS_TOKEN" default:""`
 	S2Stream      string `envconfig:"S2_STREAM"       default:""`
+
+	// OTLP telemetry export. OTLPEndpoint (host[:port]) must be set to enable
+	// the OTLP sink, which forwards telemetry events to the metro-api relay (or
+	// a collector in development).
+	OTLPEndpoint     string `envconfig:"OTLP_RELAY_ENDPOINT" default:""`
+	OTLPPath         string `envconfig:"OTLP_RELAY_PATH"     default:"/otlp-relay/v1/logs"`
+	OTLPInsecure     bool   `envconfig:"OTLP_RELAY_INSECURE" default:"false"`
+	OTLPInstanceJWT  string `envconfig:"KERNEL_INSTANCE_JWT" default:""`
+	OTLPServiceName  string `envconfig:"OTLP_SERVICE_NAME"   default:"kernel-browser"`
+	OTLPInstanceName string `envconfig:"OTLP_INSTANCE_NAME"  default:""`
+	OTLPMetro        string `envconfig:"OTLP_METRO"          default:""`
 }
 
 // LogValue implements slog.LogValuer, redacting secret fields.
@@ -55,6 +66,10 @@ func (c *Config) LogValue() slog.Value {
 	if c.S2AccessToken != "" {
 		s2AccessToken = "[redacted]"
 	}
+	otlpJWT := ""
+	if c.OTLPInstanceJWT != "" {
+		otlpJWT = "[redacted]"
+	}
 	return slog.GroupValue(
 		slog.Int("port", c.Port),
 		slog.Int("frame_rate", c.FrameRate),
@@ -73,6 +88,13 @@ func (c *Config) LogValue() slog.Value {
 		slog.String("s2_basin", c.S2Basin),
 		slog.String("s2_access_token", s2AccessToken),
 		slog.String("s2_stream", c.S2Stream),
+		slog.String("otlp_endpoint", c.OTLPEndpoint),
+		slog.String("otlp_path", c.OTLPPath),
+		slog.Bool("otlp_insecure", c.OTLPInsecure),
+		slog.String("otlp_instance_jwt", otlpJWT),
+		slog.String("otlp_service_name", c.OTLPServiceName),
+		slog.String("otlp_instance_name", c.OTLPInstanceName),
+		slog.String("otlp_metro", c.OTLPMetro),
 	)
 }
 

server/dev/otelcol/config.yaml

@@ -0,0 +1,24 @@
+# Local OTel Collector for testing the OTLP telemetry sink (Phase 1).
+# Receives OTLP/HTTP on :4318 and prints decoded records to stdout.
+#
+#   docker run --rm -p 4318:4318 \
+#     -v "$PWD/server/dev/otelcol/config.yaml":/etc/otelcol-contrib/config.yaml \
+#     otel/opentelemetry-collector-contrib:latest
+#
+# Then run the server with:
+#   OTLP_RELAY_ENDPOINT=localhost:4318 OTLP_RELAY_PATH=/v1/logs OTLP_RELAY_INSECURE=true
+receivers:
+  otlp:
+    protocols:
+      http:
+        endpoint: 0.0.0.0:4318
+
+exporters:
+  debug:
+    verbosity: detailed
+
+service:
+  pipelines:
+    logs:
+      receivers: [otlp]
+      exporters: [debug]

server/go.mod

@@ -27,9 +27,16 @@ require (
 	github.com/samber/lo v1.52.0
 	github.com/stretchr/testify v1.11.1
 	github.com/testcontainers/testcontainers-go v0.40.0
-	golang.org/x/sync v0.18.0
-	golang.org/x/sys v0.39.0
-	golang.org/x/term v0.37.0
+	go.opentelemetry.io/otel v1.44.0
+	go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploghttp v0.20.0
+	go.opentelemetry.io/otel/log v0.20.0
+	go.opentelemetry.io/otel/sdk v1.44.0
+	go.opentelemetry.io/otel/sdk/log v0.20.0
+	go.opentelemetry.io/proto/otlp v1.10.0
+	golang.org/x/sync v0.20.0
+	golang.org/x/sys v0.45.0
+	golang.org/x/term v0.43.0
+	google.golang.org/protobuf v1.36.11
 	gopkg.in/yaml.v3 v3.0.1
 )
 
@@ -39,6 +46,7 @@ require (
 	github.com/Microsoft/go-winio v0.6.2 // indirect
 	github.com/apapsch/go-jsonmerge/v2 v2.0.0 // indirect
 	github.com/cenkalti/backoff/v4 v4.3.0 // indirect
+	github.com/cenkalti/backoff/v5 v5.0.3 // indirect
 	github.com/cespare/xxhash/v2 v2.3.0 // indirect
 	github.com/containerd/errdefs v1.0.0 // indirect
 	github.com/containerd/errdefs/pkg v0.3.0 // indirect
@@ -58,7 +66,7 @@ require (
 	github.com/go-ole/go-ole v1.2.6 // indirect
 	github.com/go-openapi/jsonpointer v0.21.0 // indirect
 	github.com/go-openapi/swag v0.23.0 // indirect
-	github.com/grpc-ecosystem/grpc-gateway/v2 v2.27.2 // indirect
+	github.com/grpc-ecosystem/grpc-gateway/v2 v2.29.0 // indirect
 	github.com/jinzhu/inflection v1.0.0 // indirect
 	github.com/jinzhu/now v1.1.5 // indirect
 	github.com/josharian/intern v1.0.0 // indirect
@@ -100,21 +108,17 @@ require (
 	github.com/yusufpapurcu/wmi v1.2.4 // indirect
 	go.opentelemetry.io/auto/sdk v1.2.1 // indirect
 	go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.61.0 // indirect
-	go.opentelemetry.io/otel v1.39.0 // indirect
 	go.opentelemetry.io/otel/exporters/otlp/otlptrace v1.39.0 // indirect
-	go.opentelemetry.io/otel/metric v1.39.0 // indirect
-	go.opentelemetry.io/otel/sdk v1.39.0 // indirect
-	go.opentelemetry.io/otel/sdk/metric v1.39.0 // indirect
-	go.opentelemetry.io/otel/trace v1.39.0 // indirect
-	golang.org/x/crypto v0.44.0 // indirect
-	golang.org/x/mod v0.29.0 // indirect
-	golang.org/x/net v0.47.0 // indirect
-	golang.org/x/text v0.31.0 // indirect
-	golang.org/x/tools v0.38.0 // indirect
-	google.golang.org/genproto/googleapis/api v0.0.0-20250825161204-c5933d9347a5 // indirect
-	google.golang.org/genproto/googleapis/rpc v0.0.0-20250825161204-c5933d9347a5 // indirect
-	google.golang.org/grpc v1.75.1 // indirect
-	google.golang.org/protobuf v1.36.10 // indirect
+	go.opentelemetry.io/otel/metric v1.44.0 // indirect
+	go.opentelemetry.io/otel/trace v1.44.0 // indirect
+	golang.org/x/crypto v0.51.0 // indirect
+	golang.org/x/mod v0.35.0 // indirect
+	golang.org/x/net v0.55.0 // indirect
+	golang.org/x/text v0.37.0 // indirect
+	golang.org/x/tools v0.44.0 // indirect
+	google.golang.org/genproto/googleapis/api v0.0.0-20260526163538-3dc84a4a5aaa // indirect
+	google.golang.org/genproto/googleapis/rpc v0.0.0-20260526163538-3dc84a4a5aaa // indirect
+	google.golang.org/grpc v1.81.1 // indirect
 	gopkg.in/yaml.v2 v2.4.0 // indirect
 	gorm.io/gorm v1.25.7 // indirect
 	modernc.org/libc v1.22.5 // indirect