OTLP traces export errors use a consistent error message prefix

exporters/otlp/otlptrace/exporter.go

@@ -17,6 +17,7 @@ package otlptrace // import "go.opentelemetry.io/otel/exporters/otlp/otlptrace"
 import (
 	"context"
 	"errors"
+	"fmt"
 	"sync"
 
 	"go.opentelemetry.io/otel/exporters/otlp/otlptrace/internal/tracetransform"
@@ -45,7 +46,11 @@ func (e *Exporter) ExportSpans(ctx context.Context, ss []tracesdk.ReadOnlySpan)
 		return nil
 	}
 
-	return e.client.UploadTraces(ctx, protoSpans)
+	err := e.client.UploadTraces(ctx, protoSpans)
+	if err != nil {
+		return fmt.Errorf("trace export: %w", err)
+	}
+	return nil
 }
 
 // Start establishes a connection to the receiving endpoint.

exporters/otlp/otlptrace/exporter_test.go

@@ -0,0 +1,66 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package otlptrace_test
+
+import (
+	"context"
+	"errors"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"go.opentelemetry.io/otel/exporters/otlp/otlptrace"
+	tracesdk "go.opentelemetry.io/otel/sdk/trace"
+	"go.opentelemetry.io/otel/sdk/trace/tracetest"
+	tracepb "go.opentelemetry.io/proto/otlp/trace/v1"
+)
+
+type client struct {
+	uploadErr error
+}
+
+var _ otlptrace.Client = &client{}
+
+func (c *client) Start(ctx context.Context) error {
+	return nil
+}
+
+func (c *client) Stop(ctx context.Context) error {
+	return nil
+}
+
+func (c *client) UploadTraces(ctx context.Context, protoSpans []*tracepb.ResourceSpans) error {
+	return c.uploadErr
+}
+
+type span struct {
+	tracesdk.ReadOnlySpan
+}
+
+func TestExporterClientError(t *testing.T) {
+	ctx := context.Background()
+	exp, err := otlptrace.New(ctx, &client{
+		uploadErr: context.Canceled,
+	})
+	assert.NoError(t, err)
+
+	spans := tracetest.SpanStubs{{Name: "Span 0"}}.Snapshots()
+	err = exp.ExportSpans(ctx, spans)
+
+	assert.Error(t, err)
+	assert.True(t, errors.Is(err, context.Canceled))
+	assert.Contains(t, err.Error(), "trace export")
+
+	assert.NoError(t, exp.Shutdown(ctx))
+}

exporters/otlp/otlptrace/otlptracegrpc/client_test.go

@@ -26,9 +26,7 @@ import (
 	"github.com/stretchr/testify/require"
 	"go.uber.org/goleak"
 	"google.golang.org/grpc"
-	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/encoding/gzip"
-	"google.golang.org/grpc/status"
 
 	"go.opentelemetry.io/otel"
 	"go.opentelemetry.io/otel/attribute"
@@ -239,7 +237,8 @@ func TestExportSpansTimeoutHonored(t *testing.T) {
 	// Release the export so everything is cleaned up on shutdown.
 	close(exportBlock)
 
-	require.Equal(t, codes.DeadlineExceeded, status.Convert(err).Code())
+	require.Error(t, err)
+	require.Contains(t, err.Error(), "deadline exceeded")
 }
 
 func TestNewWithMultipleAttributeTypes(t *testing.T) {

exporters/otlp/otlptrace/otlptracehttp/client.go

@@ -197,7 +197,7 @@ func (d *client) UploadTraces(ctx context.Context, protoSpans []*tracepb.Resourc
 			}
 			return newResponseError(resp.Header)
 		default:
-			return fmt.Errorf("failed to send %s to %s: %s", d.name, request.URL, resp.Status)
+			return fmt.Errorf("failed to send to %s: %s", request.URL, resp.Status)
 		}
 	})
 }

exporters/otlp/otlptrace/otlptracehttp/client_test.go

@@ -18,7 +18,6 @@ import (
 	"context"
 	"fmt"
 	"net/http"
-	"os"
 	"testing"
 	"time"
 
@@ -219,7 +218,8 @@ func TestTimeout(t *testing.T) {
 		assert.NoError(t, exporter.Shutdown(ctx))
 	}()
 	err = exporter.ExportSpans(ctx, otlptracetest.SingleReadOnlySpan())
-	assert.Equalf(t, true, os.IsTimeout(err), "expected timeout error, got: %v", err)
+
+	assert.Contains(t, err.Error(), "deadline exceeded")
 }
 
 func TestNoRetry(t *testing.T) {
@@ -246,7 +246,7 @@ func TestNoRetry(t *testing.T) {
 	}()
 	err = exporter.ExportSpans(ctx, otlptracetest.SingleReadOnlySpan())
 	assert.Error(t, err)
-	assert.Equal(t, fmt.Sprintf("failed to send traces to http://%s/v1/traces: 400 Bad Request", mc.endpoint), err.Error())
+	assert.Equal(t, fmt.Sprintf("trace export: failed to send to http://%s/v1/traces: 400 Bad Request", mc.endpoint), err.Error())
 	assert.Empty(t, mc.GetSpans())
 }