Add OTLP exporter constructors for convenience (#353)

clue/config.go

@@ -19,19 +19,15 @@ import (
 )
 
 type (
-	// Config is used to initialize metrics and tracing.
+	// Config is used to configure OpenTelemetry.
 	Config struct {
-		// MeterProvider is the OpenTelemetry meter provider used by the clue
-		// metrics package.
+		// MeterProvider is the OpenTelemetry meter provider used by clue
 		MeterProvider metric.MeterProvider
-		// TracerProvider is the OpenTelemetry tracer provider used by the clue
-		// trace package.
+		// TracerProvider is the OpenTelemetry tracer provider used clue
 		TracerProvider trace.TracerProvider
-		// Propagators is the OpenTelemetry propagator used by the clue trace
-		// package.
+		// Propagators is the OpenTelemetry propagator used by clue
 		Propagators propagation.TextMapPropagator
-		// ErrorHandler is the error handler used by the OpenTelemetry
-		// package.
+		// ErrorHandler is the error handler used by OpenTelemetry
 		ErrorHandler otel.ErrorHandler
 	}
 )
@@ -47,9 +43,9 @@ func ConfigureOpenTelemetry(ctx context.Context, cfg *Config) {
 }
 
 // NewConfig creates a new Config object adequate for use by
-// ConfigureOpenTelemetry.  The metricsExporter and spanExporter are used to
+// ConfigureOpenTelemetry.  The metricExporter and spanExporter are used to
 // record telemetry. If either is nil then the corresponding package will not
-// record any telemetry. The OpenTelemetry metrics provider is configured with a
+// record any telemetry. The OpenTelemetry metric provider is configured with a
 // periodic reader. The OpenTelemetry tracer provider is configured to use a
 // batch span processor and an adaptive sampler that aims at a maximum sampling
 // rate of requests per second.  The resulting configuration can be modified
@@ -58,20 +54,20 @@ func ConfigureOpenTelemetry(ctx context.Context, cfg *Config) {
 //
 // Example:
 //
-//	metricsExporter, err := stdoutmetric.New()
+//	metricExporter, err := stdoutmetric.New()
 //	if err != nil {
 //		return err
 //	}
 //	spanExporter, err := stdouttrace.New()
 //	if err != nil {
 //		return err
 //	}
-//	cfg := clue.NewConfig("mysvc", "1.0.0", metricsExporter, spanExporter)
+//	cfg := clue.NewConfig("mysvc", "1.0.0", metricExporter, spanExporter)
 func NewConfig(
 	ctx context.Context,
 	svcName string,
 	svcVersion string,
-	metricsExporter sdkmetric.Exporter,
+	metricExporter sdkmetric.Exporter,
 	spanExporter sdktrace.SpanExporter,
 	opts ...Option,
 ) (*Config, error) {
@@ -90,15 +86,15 @@ func NewConfig(
 		return nil, err
 	}
 	var meterProvider metric.MeterProvider
-	if metricsExporter == nil {
+	if metricExporter == nil {
 		meterProvider = metricnoop.NewMeterProvider()
 	} else {
 		var reader sdkmetric.Reader
 		if options.readerInterval == 0 {
-			reader = sdkmetric.NewPeriodicReader(metricsExporter)
+			reader = sdkmetric.NewPeriodicReader(metricExporter)
 		} else {
 			reader = sdkmetric.NewPeriodicReader(
-				metricsExporter,
+				metricExporter,
 				sdkmetric.WithInterval(options.readerInterval),
 			)
 		}

clue/exporters.go

@@ -0,0 +1,90 @@
+package clue
+
+import (
+	"context"
+
+	"go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetricgrpc"
+	"go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp"
+	"go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc"
+	"go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp"
+	"go.opentelemetry.io/otel/sdk/metric"
+	"go.opentelemetry.io/otel/sdk/trace"
+
+	"goa.design/clue/log"
+)
+
+// Allow mocking
+var (
+	otlpmetricgrpcNew = otlpmetricgrpc.New
+	otlpmetrichttpNew = otlpmetrichttp.New
+	otlptracegrpcNew  = otlptracegrpc.New
+	otlptracehttpNew  = otlptracehttp.New
+)
+
+// NewGRPCMetricExporter returns an OpenTelementry Protocol metric exporter that
+// report metrics to a gRPC collector.
+func NewGRPCMetricExporter(ctx context.Context, options ...otlpmetricgrpc.Option) (exporter metric.Exporter, shutdown func(), err error) {
+	exporter, err = otlpmetricgrpcNew(ctx, options...)
+	if err != nil {
+		return
+	}
+	shutdown = func() {
+		// Create new context in case the parent context has been canceled.
+		ctx := log.WithContext(context.Background(), ctx)
+		if err := exporter.Shutdown(ctx); err != nil {
+			log.Errorf(ctx, err, "failed to shutdown metric exporter")
+		}
+	}
+	return
+}
+
+// NewGRPCSpanExporter returns an OpenTelementry Protocol span exporter that
+// report spans to a gRPC collector.
+func NewGRPCSpanExporter(ctx context.Context, options ...otlptracegrpc.Option) (exporter trace.SpanExporter, shutdown func(), err error) {
+	exporter, err = otlptracegrpcNew(ctx, options...)
+	if err != nil {
+		return
+	}
+	shutdown = func() {
+		// Create new context in case the parent context has been canceled.
+		ctx := log.WithContext(context.Background(), ctx)
+		if err := exporter.Shutdown(ctx); err != nil {
+			log.Errorf(ctx, err, "failed to shutdown span exporter")
+		}
+	}
+	return
+}
+
+// NewHTTPMetricExporter returns an OpenTelementry Protocol metric exporter that
+// report metrics to a HTTP collector.
+func NewHTTPMetricExporter(ctx context.Context, options ...otlpmetrichttp.Option) (exporter metric.Exporter, shutdown func(), err error) {
+	exporter, err = otlpmetrichttpNew(ctx, options...)
+	if err != nil {
+		return
+	}
+	shutdown = func() {
+		// Create new context in case the parent context has been canceled.
+		ctx := log.WithContext(context.Background(), ctx)
+		if err := exporter.Shutdown(ctx); err != nil {
+			log.Errorf(ctx, err, "failed to shutdown metric exporter")
+		}
+	}
+	return
+}
+
+// NewHTTPSpanExporter returns an OpenTelementry Protocol span exporter that
+// report spans to a HTTP collector.
+func NewHTTPSpanExporter(ctx context.Context, options ...otlptracehttp.Option) (exporter trace.SpanExporter, shutdown func(), err error) {
+	exporter, err = otlptracehttpNew(ctx, options...)
+	if err != nil {
+		return
+	}
+	shutdown = func() {
+		// Create new context in case the parent context has been canceled.
+		ctx := log.WithContext(context.Background(), ctx)
+		if err := exporter.Shutdown(ctx); err != nil {
+			log.Errorf(ctx, err, "failed to shutdown span exporter")
+		}
+	}
+	return
+}

clue/exporters_test.go

@@ -0,0 +1,224 @@
+package clue
+
+import (
+	"bytes"
+	"context"
+	"errors"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetricgrpc"
+	"go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp"
+	"go.opentelemetry.io/otel/exporters/otlp/otlptrace"
+	"go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc"
+	"go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp"
+	"goa.design/clue/log"
+)
+
+func TestNewGRPCMetricExporter(t *testing.T) {
+	testErr := errors.New("test error")
+	// Define test cases
+	tests := []struct {
+		name    string
+		options []otlpmetricgrpc.Option
+		newErr  error
+		wantLog string
+		wantErr bool
+	}{
+		{
+			name: "Success",
+		},
+		{
+			name:    "Options",
+			options: []otlpmetricgrpc.Option{otlpmetricgrpc.WithInsecure(), otlpmetricgrpc.WithEndpoint("test")},
+		},
+		{
+			name:    "New Error",
+			newErr:  testErr,
+			wantErr: true,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			otlpmetricgrpcNew = func(ctx context.Context, options ...otlpmetricgrpc.Option) (*otlpmetricgrpc.Exporter, error) {
+				if tt.newErr != nil {
+					return nil, tt.newErr
+				}
+				return otlpmetricgrpc.New(ctx)
+			}
+			var buf bytes.Buffer
+			ctx := log.Context(context.Background(), log.WithOutput(&buf))
+
+			exporter, shutdown, err := NewGRPCMetricExporter(ctx, tt.options...)
+
+			if tt.wantErr {
+				assert.Error(t, err)
+				assert.Nil(t, exporter)
+				assert.Nil(t, shutdown)
+				return
+			}
+			assert.NoError(t, err)
+			assert.NotNil(t, exporter)
+			assert.NotNil(t, shutdown)
+			shutdown()
+			assert.Empty(t, buf.String())
+		})
+	}
+}
+
+func TestNewHTTPMetricExporter(t *testing.T) {
+	testErr := errors.New("test error")
+	// Define test cases
+	tests := []struct {
+		name    string
+		options []otlpmetrichttp.Option
+		newErr  error
+		wantLog string
+		wantErr bool
+	}{
+		{
+			name: "Success",
+		},
+		{
+			name:    "Options",
+			options: []otlpmetrichttp.Option{otlpmetrichttp.WithEndpoint("test")},
+		},
+		{
+			name:    "New Error",
+			newErr:  testErr,
+			wantErr: true,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			otlpmetrichttpNew = func(ctx context.Context, options ...otlpmetrichttp.Option) (*otlpmetrichttp.Exporter, error) {
+				if tt.newErr != nil {
+					return nil, tt.newErr
+				}
+				return otlpmetrichttp.New(ctx)
+			}
+			var buf bytes.Buffer
+			ctx := log.Context(context.Background(), log.WithOutput(&buf))
+
+			exporter, shutdown, err := NewHTTPMetricExporter(ctx, tt.options...)
+
+			if tt.wantErr {
+				assert.Error(t, err)
+				assert.Nil(t, exporter)
+				assert.Nil(t, shutdown)
+				return
+			}
+			assert.NoError(t, err)
+			assert.NotNil(t, exporter)
+			assert.NotNil(t, shutdown)
+			shutdown()
+			assert.Empty(t, buf.String())
+		})
+	}
+}
+
+func TestNewGRPCSpanExporter(t *testing.T) {
+	testErr := errors.New("test error")
+	// Define test cases
+	tests := []struct {
+		name    string
+		options []otlptracegrpc.Option
+		newErr  error
+		wantLog string
+		wantErr bool
+	}{
+		{
+			name: "Success",
+		},
+		{
+			name:    "Options",
+			options: []otlptracegrpc.Option{otlptracegrpc.WithInsecure(), otlptracegrpc.WithEndpoint("test")},
+		},
+		{
+			name:    "New Error",
+			newErr:  testErr,
+			wantErr: true,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			otlptracegrpcNew = func(ctx context.Context, options ...otlptracegrpc.Option) (*otlptrace.Exporter, error) {
+				if tt.newErr != nil {
+					return nil, tt.newErr
+				}
+				return otlptracegrpc.New(ctx)
+			}
+			var buf bytes.Buffer
+			ctx := log.Context(context.Background(), log.WithOutput(&buf))
+
+			exporter, shutdown, err := NewGRPCSpanExporter(ctx, tt.options...)
+
+			if tt.wantErr {
+				assert.Error(t, err)
+				assert.Nil(t, exporter)
+				assert.Nil(t, shutdown)
+				return
+			}
+			assert.NoError(t, err)
+			assert.NotNil(t, exporter)
+			assert.NotNil(t, shutdown)
+			shutdown()
+			assert.Empty(t, buf.String())
+		})
+	}
+}
+
+func TestNewHTTPSpanExporter(t *testing.T) {
+	testErr := errors.New("test error")
+	// Define test cases
+	tests := []struct {
+		name    string
+		options []otlptracehttp.Option
+		newErr  error
+		wantLog string
+		wantErr bool
+	}{
+		{
+			name: "Success",
+		},
+		{
+			name:    "Options",
+			options: []otlptracehttp.Option{otlptracehttp.WithEndpoint("test")},
+		},
+		{
+			name:    "New Error",
+			newErr:  testErr,
+			wantErr: true,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			otlptracehttpNew = func(ctx context.Context, options ...otlptracehttp.Option) (*otlptrace.Exporter, error) {
+				if tt.newErr != nil {
+					return nil, tt.newErr
+				}
+				return otlptracehttp.New(ctx)
+			}
+			var buf bytes.Buffer
+			ctx := log.Context(context.Background(), log.WithOutput(&buf))
+
+			exporter, shutdown, err := NewHTTPSpanExporter(ctx, tt.options...)
+
+			if tt.wantErr {
+				assert.Error(t, err)
+				assert.Nil(t, exporter)
+				assert.Nil(t, shutdown)
+				return
+			}
+			assert.NoError(t, err)
+			assert.NotNil(t, exporter)
+			assert.NotNil(t, shutdown)
+			shutdown()
+			assert.Empty(t, buf.String())
+		})
+	}
+}