Shut down all processors even on error (#3091)

sdk/trace/provider.go

@@ -248,10 +248,7 @@ func (p *TracerProvider) Shutdown(ctx context.Context) error {
 	if !ok {
 		return fmt.Errorf("failed to load span processors")
 	}
-	if len(spss) == 0 {
-		return nil
-	}
-
+	var retErr error
 	for _, sps := range spss {
 		select {
 		case <-ctx.Done():
@@ -264,10 +261,15 @@ func (p *TracerProvider) Shutdown(ctx context.Context) error {
 			err = sps.sp.Shutdown(ctx)
 		})
 		if err != nil {
-			return err
+			if retErr == nil {
+				retErr = err
+			} else {
+				// Poor man's list of errors
+				retErr = fmt.Errorf("%v; %v", retErr, err)
+			}
 		}
 	}
-	return nil
+	return retErr
 }
 
 // TracerProviderOption configures a TracerProvider.

sdk/trace/provider_test.go

@@ -72,6 +72,28 @@ func TestFailedProcessorShutdown(t *testing.T) {
 	assert.Equal(t, err, spErr)
 }
 
+func TestFailedProcessorsShutdown(t *testing.T) {
+	stp := NewTracerProvider()
+	spErr1 := errors.New("basic span processor shutdown failure1")
+	spErr2 := errors.New("basic span processor shutdown failure2")
+	sp1 := &basicSpanProcesor{
+		running:             true,
+		injectShutdownError: spErr1,
+	}
+	sp2 := &basicSpanProcesor{
+		running:             true,
+		injectShutdownError: spErr2,
+	}
+	stp.RegisterSpanProcessor(sp1)
+	stp.RegisterSpanProcessor(sp2)
+
+	err := stp.Shutdown(context.Background())
+	assert.Error(t, err)
+	assert.EqualError(t, err, "basic span processor shutdown failure1; basic span processor shutdown failure2")
+	assert.False(t, sp1.running)
+	assert.False(t, sp2.running)
+}
+
 func TestFailedProcessorShutdownInUnregister(t *testing.T) {
 	handler.Reset()
 	stp := NewTracerProvider()