feat: add log support for autoexport (#5733)

Resolve #5730

---------

Co-authored-by: Tyler Yahn <[email protected]>

Author: sysulq

CHANGELOG.md

@@ -12,6 +12,7 @@ This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.htm
 
 - The `go.opentelemetry.io/contrib/config` add support to configure periodic reader interval and timeout. (#5661)
 - Add support to configure views when creating MeterProvider using the config package. (#5654)
+- Add log support for the autoexport package. (#5733)
 
 ### Fixed
 

exporters/autoexport/go.mod

@@ -8,15 +8,18 @@ require (
 	go.opentelemetry.io/collector/pdata v1.8.0
 	go.opentelemetry.io/contrib/bridges/prometheus v0.52.0
 	go.opentelemetry.io/otel v1.27.0
+	go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploghttp v0.3.0
 	go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetricgrpc v1.27.0
 	go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp v1.27.0
 	go.opentelemetry.io/otel/exporters/otlp/otlptrace v1.27.0
 	go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc v1.27.0
 	go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp v1.27.0
 	go.opentelemetry.io/otel/exporters/prometheus v0.49.0
+	go.opentelemetry.io/otel/exporters/stdout/stdoutlog v0.3.0
 	go.opentelemetry.io/otel/exporters/stdout/stdoutmetric v1.27.0
 	go.opentelemetry.io/otel/exporters/stdout/stdouttrace v1.27.0
 	go.opentelemetry.io/otel/sdk v1.27.0
+	go.opentelemetry.io/otel/sdk/log v0.3.0
 	go.opentelemetry.io/otel/sdk/metric v1.27.0
 	go.uber.org/goleak v1.3.0
 )
@@ -37,6 +40,7 @@ require (
 	github.com/prometheus/client_model v0.6.1 // indirect
 	github.com/prometheus/common v0.54.0 // indirect
 	github.com/prometheus/procfs v0.15.1 // indirect
+	go.opentelemetry.io/otel/log v0.3.0 // indirect
 	go.opentelemetry.io/otel/metric v1.27.0 // indirect
 	go.opentelemetry.io/otel/trace v1.27.0 // indirect
 	go.opentelemetry.io/proto/otlp v1.2.0 // indirect

exporters/autoexport/go.sum

@@ -54,6 +54,8 @@ go.opentelemetry.io/collector/pdata v1.8.0 h1:d/QQgZxB4Y+d3mqLVh2ozvzujUhloD3P/f
 go.opentelemetry.io/collector/pdata v1.8.0/go.mod h1:/W7clu0wFC4WSRp94Ucn6Vm36Wkrt+tmtlDb1aiNZCY=
 go.opentelemetry.io/otel v1.27.0 h1:9BZoF3yMK/O1AafMiQTVu0YDj5Ea4hPhxCs7sGva+cg=
 go.opentelemetry.io/otel v1.27.0/go.mod h1:DMpAK8fzYRzs+bi3rS5REupisuqTheUlSZJ1WnZaPAQ=
+go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploghttp v0.3.0 h1:ccBrA8nCY5mM0y5uO7FT0ze4S0TuFcWdDB2FxGMTjkI=
+go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploghttp v0.3.0/go.mod h1:/9pb6634zi2Lk8LYg9Q0X8Ar6jka4dkFOylBLbVQPCE=
 go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetricgrpc v1.27.0 h1:bFgvUr3/O4PHj3VQcFEuYKvRZJX1SJDQ+11JXuSB3/w=
 go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetricgrpc v1.27.0/go.mod h1:xJntEd2KL6Qdg5lwp97HMLQDVeAhrYxmzFseAMDPQ8I=
 go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp v1.27.0 h1:CIHWikMsN3wO+wq1Tp5VGdVRTcON+DmOJSfDjXypKOc=
@@ -66,14 +68,20 @@ go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp v1.27.0 h1:QY7/0
 go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp v1.27.0/go.mod h1:HVkSiDhTM9BoUJU8qE6j2eSWLLXvi1USXjyd2BXT8PY=
 go.opentelemetry.io/otel/exporters/prometheus v0.49.0 h1:Er5I1g/YhfYv9Affk9nJLfH/+qCCVVg1f2R9AbJfqDQ=
 go.opentelemetry.io/otel/exporters/prometheus v0.49.0/go.mod h1:KfQ1wpjf3zsHjzP149P4LyAwWRupc6c7t1ZJ9eXpKQM=
+go.opentelemetry.io/otel/exporters/stdout/stdoutlog v0.3.0 h1:6aGq6rMOdOx9B385JpF1OpeL18+6Ho8bTFdxy10oEGY=
+go.opentelemetry.io/otel/exporters/stdout/stdoutlog v0.3.0/go.mod h1:fdZI+pB2Y6Dpl3Uf+1ZPrkX6cnwsUAhjK1f9yCAlJIM=
 go.opentelemetry.io/otel/exporters/stdout/stdoutmetric v1.27.0 h1:/jlt1Y8gXWiHG9FBx6cJaIC5hYx5Fe64nC8w5Cylt/0=
 go.opentelemetry.io/otel/exporters/stdout/stdoutmetric v1.27.0/go.mod h1:bmToOGOBZ4hA9ghphIc1PAf66VA8KOtsuy3+ScStG20=
 go.opentelemetry.io/otel/exporters/stdout/stdouttrace v1.27.0 h1:/0YaXu3755A/cFbtXp+21lkXgI0QE5avTWA2HjU9/WE=
 go.opentelemetry.io/otel/exporters/stdout/stdouttrace v1.27.0/go.mod h1:m7SFxp0/7IxmJPLIY3JhOcU9CoFzDaCPL6xxQIxhA+o=
+go.opentelemetry.io/otel/log v0.3.0 h1:kJRFkpUFYtny37NQzL386WbznUByZx186DpEMKhEGZs=
+go.opentelemetry.io/otel/log v0.3.0/go.mod h1:ziCwqZr9soYDwGNbIL+6kAvQC+ANvjgG367HVcyR/ys=
 go.opentelemetry.io/otel/metric v1.27.0 h1:hvj3vdEKyeCi4YaYfNjv2NUje8FqKqUY8IlF0FxV/ik=
 go.opentelemetry.io/otel/metric v1.27.0/go.mod h1:mVFgmRlhljgBiuk/MP/oKylr4hs85GZAylncepAX/ak=
 go.opentelemetry.io/otel/sdk v1.27.0 h1:mlk+/Y1gLPLn84U4tI8d3GNJmGT/eXe3ZuOXN9kTWmI=
 go.opentelemetry.io/otel/sdk v1.27.0/go.mod h1:Ha9vbLwJE6W86YstIywK2xFfPjbWlCuwPtMkKdz/Y4A=
+go.opentelemetry.io/otel/sdk/log v0.3.0 h1:GEjJ8iftz2l+XO1GF2856r7yYVh74URiF9JMcAacr5U=
+go.opentelemetry.io/otel/sdk/log v0.3.0/go.mod h1:BwCxtmux6ACLuys1wlbc0+vGBd+xytjmjajwqqIul2g=
 go.opentelemetry.io/otel/sdk/metric v1.27.0 h1:5uGNOlpXi+Hbo/DRoI31BSb1v+OGcpv2NemcCrOL8gI=
 go.opentelemetry.io/otel/sdk/metric v1.27.0/go.mod h1:we7jJVrYN2kh3mVBlswtPU22K0SA+769l93J6bsyvqw=
 go.opentelemetry.io/otel/trace v1.27.0 h1:IqYb813p7cmbHk0a5y6pD5JPakbVfftRXABGt5/Rscw=

exporters/autoexport/logs.go

@@ -0,0 +1,75 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package autoexport // import "go.opentelemetry.io/contrib/exporters/autoexport"
+
+import (
+	"context"
+	"os"
+
+	"go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploghttp"
+	"go.opentelemetry.io/otel/exporters/stdout/stdoutlog"
+	"go.opentelemetry.io/otel/sdk/log"
+)
+
+// LogOption applies an autoexport configuration option.
+type LogOption = option[log.Exporter]
+
+var logsSignal = newSignal[log.Exporter]("OTEL_LOGS_EXPORTER")
+
+// NewLogExporter returns a configured [go.opentelemetry.io/otel/sdk/log.Exporter]
+// defined using the environment variables described below.
+//
+// OTEL_LOGS_EXPORTER defines the logs exporter; supported values:
+//   - "none" - "no operation" exporter
+//   - "otlp" (default) - OTLP exporter; see [go.opentelemetry.io/otel/exporters/otlp/otlplog]
+//   - "console" - Standard output exporter; see [go.opentelemetry.io/otel/exporters/stdout/stdoutlog]
+//
+// OTEL_EXPORTER_OTLP_PROTOCOL defines OTLP exporter's transport protocol;
+// supported values:
+//   - "http/protobuf" (default) -  protobuf-encoded data over HTTP connection;
+//     see: [go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploghttp]
+//
+// An error is returned if an environment value is set to an unhandled value.
+//
+// Use [RegisterLogExporter] to handle more values of OTEL_LOGS_EXPORTER.
+//
+// Use [WithFallbackLogExporter] option to change the returned exporter
+// when OTEL_LOGS_EXPORTER is unset or empty.
+//
+// Use [IsNoneLogExporter] to check if the returned exporter is a "no operation" exporter.
+func NewLogExporter(ctx context.Context, opts ...LogOption) (log.Exporter, error) {
+	return logsSignal.create(ctx, opts...)
+}
+
+// RegisterLogExporter sets the log.Exporter factory to be used when the
+// OTEL_LOGS_EXPORTER environment variable contains the exporter name.
+// This will panic if name has already been registered.
+func RegisterLogExporter(name string, factory func(context.Context) (log.Exporter, error)) {
+	must(logsSignal.registry.store(name, factory))
+}
+
+func init() {
+	RegisterLogExporter("otlp", func(ctx context.Context) (log.Exporter, error) {
+		proto := os.Getenv(otelExporterOTLPProtoEnvKey)
+		if proto == "" {
+			proto = "http/protobuf"
+		}
+
+		switch proto {
+		// grpc is not supported yet, should comment out when it is supported
+		// case "grpc":
+		// 	return otlploggrpc.New(ctx)
+		case "http/protobuf":
+			return otlploghttp.New(ctx)
+		default:
+			return nil, errInvalidOTLPProtocol
+		}
+	})
+	RegisterLogExporter("console", func(ctx context.Context) (log.Exporter, error) {
+		return stdoutlog.New()
+	})
+	RegisterLogExporter("none", func(ctx context.Context) (log.Exporter, error) {
+		return noopLogExporter{}, nil
+	})
+}

exporters/autoexport/logs_test.go

@@ -0,0 +1,69 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package autoexport // import "go.opentelemetry.io/contrib/exporters/autoexport"
+
+import (
+	"context"
+	"fmt"
+	"reflect"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+
+	"go.opentelemetry.io/otel/exporters/stdout/stdoutlog"
+	"go.opentelemetry.io/otel/sdk/log"
+)
+
+func TestLogExporterNone(t *testing.T) {
+	t.Setenv("OTEL_LOGS_EXPORTER", "none")
+	got, err := NewLogExporter(context.Background())
+	assert.NoError(t, err)
+	t.Cleanup(func() {
+		assert.NoError(t, got.ForceFlush(context.Background()))
+		assert.NoError(t, got.Shutdown(context.Background()))
+	})
+	assert.NoError(t, got.Export(context.Background(), nil))
+	assert.True(t, IsNoneLogExporter(got))
+}
+
+func TestLogExporterConsole(t *testing.T) {
+	t.Setenv("OTEL_LOGS_EXPORTER", "console")
+	got, err := NewLogExporter(context.Background())
+	assert.NoError(t, err)
+	assert.IsType(t, &stdoutlog.Exporter{}, got)
+}
+
+func TestLogExporterOTLP(t *testing.T) {
+	t.Setenv("OTEL_LOGS_EXPORTER", "otlp")
+
+	for _, tc := range []struct {
+		protocol, clientType string
+	}{
+		{"http/protobuf", "atomic.Pointer[go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploghttp.client]"},
+		{"", "atomic.Pointer[go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploghttp.client]"},
+	} {
+		t.Run(fmt.Sprintf("protocol=%q", tc.protocol), func(t *testing.T) {
+			t.Setenv("OTEL_EXPORTER_OTLP_PROTOCOL", tc.protocol)
+
+			got, err := NewLogExporter(context.Background())
+			assert.NoError(t, err)
+			t.Cleanup(func() {
+				assert.NoError(t, got.Shutdown(context.Background()))
+			})
+			assert.Implements(t, new(log.Exporter), got)
+
+			// Implementation detail hack. This may break when bumping OTLP exporter modules as it uses unexported API.
+			clientType := reflect.Indirect(reflect.ValueOf(got)).FieldByName("client").Type()
+			assert.Equal(t, tc.clientType, clientType.String())
+		})
+	}
+}
+
+func TestLogExporterOTLPOverInvalidProtocol(t *testing.T) {
+	t.Setenv("OTEL_LOGS_EXPORTER", "otlp")
+	t.Setenv("OTEL_EXPORTER_OTLP_PROTOCOL", "invalid-protocol")
+
+	_, err := NewLogExporter(context.Background())
+	assert.Error(t, err)
+}

exporters/autoexport/noop.go

@@ -6,6 +6,7 @@ package autoexport // import "go.opentelemetry.io/contrib/exporters/autoexport"
 import (
 	"context"
 
+	"go.opentelemetry.io/otel/sdk/log"
 	"go.opentelemetry.io/otel/sdk/metric"
 	"go.opentelemetry.io/otel/sdk/metric/metricdata"
 	"go.opentelemetry.io/otel/sdk/trace"
@@ -57,3 +58,30 @@ func (e noopMetricProducer) Produce(ctx context.Context) ([]metricdata.ScopeMetr
 func newNoopMetricProducer() noopMetricProducer {
 	return noopMetricProducer{}
 }
+
+// noopLogExporter is an implementation of log.SpanExporter that performs no operations.
+type noopLogExporter struct{}
+
+var _ log.Exporter = noopLogExporter{}
+
+// ExportSpans is part of log.Exporter interface.
+func (e noopLogExporter) Export(ctx context.Context, records []log.Record) error {
+	return nil
+}
+
+// Shutdown is part of log.Exporter interface.
+func (e noopLogExporter) Shutdown(ctx context.Context) error {
+	return nil
+}
+
+// ForceFlush is part of log.Exporter interface.
+func (e noopLogExporter) ForceFlush(ctx context.Context) error {
+	return nil
+}
+
+// IsNoneLogExporter returns true for the exporter returned by [NewLogExporter]
+// when OTEL_LOGSS_EXPORTER environment variable is set to "none".
+func IsNoneLogExporter(e log.Exporter) bool {
+	_, ok := e.(noopLogExporter)
+	return ok
+}