DOL-23: add optional OTLP log export

backend/cmd/server/wire.go

@@ -90,6 +90,7 @@ func provideCleanup(
 	opsCleanup *service.OpsCleanupService,
 	opsScheduledReport *service.OpsScheduledReportService,
 	opsSystemLogSink *service.OpsSystemLogSink,
+	otlpLogSink *service.OTLPLogSink,
 	opsService *service.OpsService,
 	opsIngressReject *service.OpsIngressRejectAggregator,
 	apiKeyService *service.APIKeyService,
@@ -200,6 +201,12 @@ func provideCleanup(
 				}
 				return nil
 			}},
+			{"OTLPLogSink", func() error {
+				if otlpLogSink != nil {
+					return otlpLogSink.Shutdown(ctx)
+				}
+				return nil
+			}},
 			{"AuditLogService", func() error {
 				if auditLog != nil {
 					auditLog.Stop()

backend/cmd/server/wire_gen_test.go

@@ -59,6 +59,7 @@ func TestProvideCleanup_WithMinimalDependencies_NoPanic(t *testing.T) {
 		&service.OpsCleanupService{},
 		&service.OpsScheduledReportService{},
 		opsSystemLogSinkSvc,
+		nil, // otlpLogSink
 		nil, // opsService
 		nil, // opsIngressRejectAggregator
 		nil, // apiKeyService

backend/go.mod

@@ -49,6 +49,12 @@ require (
 	github.com/tiktoken-go/tokenizer v0.8.0
 	github.com/wechatpay-apiv3/wechatpay-go v0.2.21
 	github.com/zeromicro/go-zero v1.9.4
+	go.opentelemetry.io/otel v1.43.0
+	go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploggrpc v0.19.0
+	go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploghttp v0.19.0
+	go.opentelemetry.io/otel/log v0.19.0
+	go.opentelemetry.io/otel/sdk v1.43.0
+	go.opentelemetry.io/otel/sdk/log v0.19.0
 	go.uber.org/zap v1.24.0
 	golang.org/x/crypto v0.53.0
 	golang.org/x/image v0.41.0
@@ -93,6 +99,7 @@ require (
 	github.com/boombuler/barcode v1.0.1-0.20190219062509-6c824513bacc // indirect
 	github.com/bytedance/sonic v1.9.1 // indirect
 	github.com/cenkalti/backoff/v4 v4.3.0 // indirect
+	github.com/cenkalti/backoff/v5 v5.0.3 // indirect
 	github.com/chenzhuoyu/base64x v0.0.0-20221115062448-fe3a3abad311 // indirect
 	github.com/clbanning/mxj/v2 v2.7.0 // indirect
 	github.com/containerd/errdefs v1.0.0 // indirect
@@ -129,7 +136,7 @@ require (
 	github.com/google/go-cmp v0.7.0 // indirect
 	github.com/google/go-querystring v1.1.0 // indirect
 	github.com/google/go-tpm v0.9.8 // indirect
-	github.com/grpc-ecosystem/grpc-gateway/v2 v2.27.3 // indirect
+	github.com/grpc-ecosystem/grpc-gateway/v2 v2.28.0 // indirect
 	github.com/hashicorp/hcl v1.0.0 // indirect
 	github.com/hashicorp/hcl/v2 v2.18.1 // indirect
 	github.com/hashicorp/yamux v0.1.2 // indirect
@@ -194,9 +201,9 @@ require (
 	github.com/zclconf/go-cty-yaml v1.1.0 // indirect
 	go.opentelemetry.io/auto/sdk v1.2.1 // indirect
 	go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.49.0 // indirect
-	go.opentelemetry.io/otel v1.43.0 // indirect
 	go.opentelemetry.io/otel/metric v1.43.0 // indirect
 	go.opentelemetry.io/otel/trace v1.43.0 // indirect
+	go.opentelemetry.io/proto/otlp v1.10.0 // indirect
 	go.uber.org/atomic v1.10.0 // indirect
 	go.uber.org/automaxprocs v1.6.0 // indirect
 	go.uber.org/multierr v1.9.0 // indirect
@@ -206,6 +213,7 @@ require (
 	golang.org/x/text v0.39.0 // indirect
 	golang.org/x/time v0.12.0 // indirect
 	golang.org/x/tools v0.47.0 // indirect
+	google.golang.org/genproto/googleapis/api v0.0.0-20260414002931-afd174a4e478 // indirect
 	google.golang.org/genproto/googleapis/rpc v0.0.0-20260414002931-afd174a4e478 // indirect
 	gopkg.in/ini.v1 v1.67.0 // indirect
 	modernc.org/libc v1.67.6 // indirect

backend/go.sum

@@ -127,6 +127,8 @@ github.com/bytedance/sonic v1.9.1 h1:6iJ6NqdoxCDr6mbY8h18oSO+cShGSMRGCEo7F2h0x8s
 github.com/bytedance/sonic v1.9.1/go.mod h1:i736AoUSYt75HyZLoJW9ERYxcy6eaN6h4BZXU064P/U=
 github.com/cenkalti/backoff/v4 v4.3.0 h1:MyRJ/UdXutAwSAT+s3wNd7MfTIcy71VQueUuFK343L8=
 github.com/cenkalti/backoff/v4 v4.3.0/go.mod h1:Y3VNntkOUPxTVeUxJ/G5vcM//AlwfmyYozVcomhLiZE=
+github.com/cenkalti/backoff/v5 v5.0.3 h1:ZN+IMa753KfX5hd8vVaMixjnqRZ3y8CuJKRKj1xcsSM=
+github.com/cenkalti/backoff/v5 v5.0.3/go.mod h1:rkhZdG3JZukswDf7f0cwqPNk4K0sa+F97BxZthm/crw=
 github.com/census-instrumentation/opencensus-proto v0.2.1/go.mod h1:f6KPmirojxKA12rnyqOA5BBL4O983OfeGPqjHWSTneU=
 github.com/cespare/xxhash/v2 v2.3.0 h1:UL815xU9SqsFlibzuggzjXhog7bL6oX9BbNZnL2UFvs=
 github.com/cespare/xxhash/v2 v2.3.0/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
@@ -263,8 +265,8 @@ github.com/gopherjs/gopherjs v0.0.0-20181017120253-0766667cb4d1/go.mod h1:wJfORR
 github.com/gopherjs/gopherjs v0.0.0-20200217142428-fce0ec30dd00/go.mod h1:wJfORRmW1u3UXTncJ5qlYoELFm8eSnnEO6hX4iZ3EWY=
 github.com/gorilla/websocket v1.5.3 h1:saDtZ6Pbx/0u+bgYQ3q96pZgCzfhKXGPqt7kZ72aNNg=
 github.com/gorilla/websocket v1.5.3/go.mod h1:YR8l580nyteQvAITg2hZ9XVh4b55+EU/adAjf1fMHhE=
-github.com/grpc-ecosystem/grpc-gateway/v2 v2.27.3 h1:NmZ1PKzSTQbuGHw9DGPFomqkkLWMC+vZCkfs+FHv1Vg=
-github.com/grpc-ecosystem/grpc-gateway/v2 v2.27.3/go.mod h1:zQrxl1YP88HQlA6i9c63DSVPFklWpGX4OWAc9bFuaH4=
+github.com/grpc-ecosystem/grpc-gateway/v2 v2.28.0 h1:HWRh5R2+9EifMyIHV7ZV+MIZqgz+PMpZ14Jynv3O2Zs=
+github.com/grpc-ecosystem/grpc-gateway/v2 v2.28.0/go.mod h1:JfhWUomR1baixubs02l85lZYYOm7LV6om4ceouMv45c=
 github.com/hashicorp/go-hclog v1.6.3 h1:Qr2kF+eVWjTiYmU7Y31tYlP1h0q/X3Nl3tPGdaB11/k=
 github.com/hashicorp/go-hclog v1.6.3/go.mod h1:W4Qnvbt70Wk/zYJryRzDRU/4r0kIg0PVHBcfoyhpF5M=
 github.com/hashicorp/go-plugin v1.8.0 h1:ie8S6RRY8RvB2usYZv+AAZ/wBvx2AU5p5QeP5j/FORs=
@@ -519,20 +521,30 @@ go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.49.0 h1:jq9TW8u
 go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.49.0/go.mod h1:p8pYQP+m5XfbZm9fxtSKAbM6oIllS7s2AfxrChvc7iw=
 go.opentelemetry.io/otel v1.43.0 h1:mYIM03dnh5zfN7HautFE4ieIig9amkNANT+xcVxAj9I=
 go.opentelemetry.io/otel v1.43.0/go.mod h1:JuG+u74mvjvcm8vj8pI5XiHy1zDeoCS2LB1spIq7Ay0=
+go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploggrpc v0.19.0 h1:Dn8rkudDzY6KV9dr/D/bTUuWgqDf9xe0rr4G2elrn0Y=
+go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploggrpc v0.19.0/go.mod h1:gMk9F0xDgyN9M/3Ed5Y1wKcx/9mlU91NXY2SNq7RQuU=
+go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploghttp v0.19.0 h1:HIBTQ3VO5aupLKjC90JgMqpezVXwFuq6Ryjn0/izoag=
+go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploghttp v0.19.0/go.mod h1:ji9vId85hMxqfvICA0Jt8JqEdrXaAkcpkI9HPXya0ro=
 go.opentelemetry.io/otel/exporters/otlp/otlptrace v1.24.0 h1:t6wl9SPayj+c7lEIFgm4ooDBZVb01IhLB4InpomhRw8=
 go.opentelemetry.io/otel/exporters/otlp/otlptrace v1.24.0/go.mod h1:iSDOcsnSA5INXzZtwaBPrKp/lWu/V14Dd+llD0oI2EA=
 go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp v1.24.0 h1:Xw8U6u2f8DK2XAkGRFV7BBLENgnTGX9i4rQRxJf+/vs=
 go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp v1.24.0/go.mod h1:6KW1Fm6R/s6Z3PGXwSJN2K4eT6wQB3vXX6CVnYX9NmM=
+go.opentelemetry.io/otel/log v0.19.0 h1:KUZs/GOsw79TBBMfDWsXS+KZ4g2Ckzksd1ymzsIEbo4=
+go.opentelemetry.io/otel/log v0.19.0/go.mod h1:5DQYeGmxVIr4n0/BcJvF4upsraHjg6vudJJpnkL6Ipk=
 go.opentelemetry.io/otel/metric v1.43.0 h1:d7638QeInOnuwOONPp4JAOGfbCEpYb+K6DVWvdxGzgM=
 go.opentelemetry.io/otel/metric v1.43.0/go.mod h1:RDnPtIxvqlgO8GRW18W6Z/4P462ldprJtfxHxyKd2PY=
 go.opentelemetry.io/otel/sdk v1.43.0 h1:pi5mE86i5rTeLXqoF/hhiBtUNcrAGHLKQdhg4h4V9Dg=
 go.opentelemetry.io/otel/sdk v1.43.0/go.mod h1:P+IkVU3iWukmiit/Yf9AWvpyRDlUeBaRg6Y+C58QHzg=
+go.opentelemetry.io/otel/sdk/log v0.19.0 h1:scYVLqT22D2gqXItnWiocLUKGH9yvkkeql5dBDiXyko=
+go.opentelemetry.io/otel/sdk/log v0.19.0/go.mod h1:vFBowwXGLlW9AvpuF7bMgnNI95LiW10szrOdvzBHlAg=
+go.opentelemetry.io/otel/sdk/log/logtest v0.19.0 h1:BEbF7ZBB6qQloV/Ub1+3NQoOUnVtcGkU3XX4Ws3GQfk=
+go.opentelemetry.io/otel/sdk/log/logtest v0.19.0/go.mod h1:Lua81/3yM0wOmoHTokLj9y9ADeA02v1naRrVrkAZuKk=
 go.opentelemetry.io/otel/sdk/metric v1.43.0 h1:S88dyqXjJkuBNLeMcVPRFXpRw2fuwdvfCGLEo89fDkw=
 go.opentelemetry.io/otel/sdk/metric v1.43.0/go.mod h1:C/RJtwSEJ5hzTiUz5pXF1kILHStzb9zFlIEe85bhj6A=
 go.opentelemetry.io/otel/trace v1.43.0 h1:BkNrHpup+4k4w+ZZ86CZoHHEkohws8AY+WTX09nk+3A=
 go.opentelemetry.io/otel/trace v1.43.0/go.mod h1:/QJhyVBUUswCphDVxq+8mld+AvhXZLhe+8WVFxiFff0=
-go.opentelemetry.io/proto/otlp v1.3.1 h1:TrMUixzpM0yuc/znrFTP9MMRh8trP93mkCiDVeXrui0=
-go.opentelemetry.io/proto/otlp v1.3.1/go.mod h1:0X1WI4de4ZsLrrJNLAQbFeLCm3T7yBkR0XqQ7niQU+8=
+go.opentelemetry.io/proto/otlp v1.10.0 h1:IQRWgT5srOCYfiWnpqUYz9CVmbO8bFmKcwYxpuCSL2g=
+go.opentelemetry.io/proto/otlp v1.10.0/go.mod h1:/CV4QoCR/S9yaPj8utp3lvQPoqMtxXdzn7ozvvozVqk=
 go.uber.org/atomic v1.10.0 h1:9qC72Qh0+3MqyJbAn8YU5xVq1frD8bn3JtD2oXtafVQ=
 go.uber.org/atomic v1.10.0/go.mod h1:LUxbIzbOniOlMKjJjyPfpl4v+PKK2cNJn91OQbhoJI0=
 go.uber.org/automaxprocs v1.6.0 h1:O3y2/QNTOdbF+e/dpXNNW7Rx2hZ4sTIPyybbxyNqTUs=
@@ -701,7 +713,6 @@ google.golang.org/appengine v1.1.0/go.mod h1:EbEs0AVv82hx2wNQdGPgUI5lhzA/G0D9Ywl
 google.golang.org/appengine v1.4.0/go.mod h1:xpcJRLb0r/rnEns0DIKYYv+WjYCduHsrkT7/EB5XEv4=
 google.golang.org/genproto v0.0.0-20180817151627-c66870c02cf8/go.mod h1:JiN7NxoALGmiZfu7CAH4rXhgtRTLTxftemlI0sWmxmc=
 google.golang.org/genproto v0.0.0-20190819201941-24fa4b261c55/go.mod h1:DMBHOl98Agz4BDEuKkezgsaosCRResVns1a3J2ZsMNc=
-google.golang.org/genproto v0.0.0-20231106174013-bbf56f31fb17 h1:wpZ8pe2x1Q3f2KyT5f8oP/fa9rHAKgFPr/HZdNuS+PQ=
 google.golang.org/genproto/googleapis/api v0.0.0-20260414002931-afd174a4e478 h1:yQugLulqltosq0B/f8l4w9VryjV+N/5gcW0jQ3N8Qec=
 google.golang.org/genproto/googleapis/api v0.0.0-20260414002931-afd174a4e478/go.mod h1:C6ADNqOxbgdUUeRTU+LCHDPB9ttAMCTff6auwCVa4uc=
 google.golang.org/genproto/googleapis/rpc v0.0.0-20260414002931-afd174a4e478 h1:RmoJA1ujG+/lRGNfUnOMfhCy5EipVMyvUE+KNbPbTlw=

backend/internal/pkg/logger/multi_sink.go

@@ -0,0 +1,51 @@
+package logger
+
+import "reflect"
+
+// multiSink forwards each log event to all configured sinks.
+// Sinks are invoked in registration order.
+type multiSink struct {
+	sinks []Sink
+}
+
+// NewMultiSink combines multiple sinks without changing the single-sink fast
+// path. Nil sinks are ignored; no sinks returns nil.
+func NewMultiSink(sinks ...Sink) Sink {
+	filtered := make([]Sink, 0, len(sinks))
+	for _, sink := range sinks {
+		if !nilSink(sink) {
+			filtered = append(filtered, sink)
+		}
+	}
+
+	switch len(filtered) {
+	case 0:
+		return nil
+	case 1:
+		return filtered[0]
+	default:
+		return &multiSink{sinks: filtered}
+	}
+}
+
+func nilSink(sink Sink) bool {
+	if sink == nil {
+		return true
+	}
+	value := reflect.ValueOf(sink)
+	switch value.Kind() {
+	case reflect.Chan, reflect.Func, reflect.Interface, reflect.Map, reflect.Pointer, reflect.Slice:
+		return value.IsNil()
+	default:
+		return false
+	}
+}
+
+func (s *multiSink) WriteLogEvent(event *LogEvent) {
+	if s == nil || event == nil {
+		return
+	}
+	for _, sink := range s.sinks {
+		sink.WriteLogEvent(event)
+	}
+}

backend/internal/pkg/logger/multi_sink_test.go

@@ -0,0 +1,44 @@
+package logger
+
+import (
+	"testing"
+	"time"
+)
+
+type recordingSink struct {
+	events []*LogEvent
+}
+
+func (s *recordingSink) WriteLogEvent(event *LogEvent) {
+	s.events = append(s.events, event)
+}
+
+func TestNewMultiSink(t *testing.T) {
+	first := &recordingSink{}
+	second := &recordingSink{}
+	event := &LogEvent{Time: time.Now(), Message: "hello"}
+
+	sink := NewMultiSink(nil, first, second)
+	if sink == nil {
+		t.Fatal("expected combined sink")
+	}
+	sink.WriteLogEvent(event)
+
+	for name, recorder := range map[string]*recordingSink{"first": first, "second": second} {
+		if len(recorder.events) != 1 || recorder.events[0] != event {
+			t.Fatalf("%s sink did not receive the event", name)
+		}
+	}
+}
+
+func TestNewMultiSinkFastPaths(t *testing.T) {
+	if sink := NewMultiSink(nil); sink != nil {
+		t.Fatalf("expected nil sink, got %T", sink)
+	}
+
+	only := &recordingSink{}
+	var typedNil *recordingSink
+	if sink := NewMultiSink(nil, only, typedNil); sink != only {
+		t.Fatalf("expected the original single sink, got %T", sink)
+	}
+}