separate onError to OnNextError and OnExtractionError (#6)

Author: aldas

.github/workflows/checks.yml

@@ -41,9 +41,7 @@ jobs:
 
       - name: Run gosec
         run: |
-# 2026-02-16: gosec is broken for multi-module repos, so we use v2.23.0 instead of the latest version.
-#          go install github.com/securego/gosec/v2/cmd/gosec@latest
-          go install github.com/securego/gosec/v2/cmd/gosec@v2.23.0
+          go install github.com/securego/gosec/v2/cmd/gosec@master
           gosec -exclude-dir=.cache ./...
 
       - name: Run govulncheck

otel.go

@@ -49,8 +49,11 @@ type Config struct {
 	// Skipper defines a function to skip middleware.
 	Skipper middleware.Skipper
 
-	// OnErrorFn is used to specify how errors are handled in the middleware.
-	OnError OnErrorFunc
+	// OnNextError is used to specify how errors returned from the next middleware / handler are handled.
+	OnNextError OnErrorFunc
+
+	// OnExtractionError is used to specify how errors returned from request extraction are handled.
+	OnExtractionError OnErrorFunc
 
 	// TracerProvider allows overriding the default tracer provider.
 	TracerProvider oteltrace.TracerProvider
@@ -119,11 +122,6 @@ func (config Config) ToMiddleware() (echo.MiddlewareFunc, error) {
 	if config.Skipper == nil {
 		config.Skipper = middleware.DefaultSkipper
 	}
-	if config.OnError == nil {
-		config.OnError = func(c *echo.Context, err error) {
-			c.Logger().Error("otel middleware error", "error", err)
-		}
-	}
 
 	var serverHost string
 	var serverPort int
@@ -175,7 +173,9 @@ func (config Config) ToMiddleware() (echo.MiddlewareFunc, error) {
 				ClientAddress: c.RealIP(),
 			}
 			if err := ev.ExtractRequest(request); err != nil {
-				config.OnError(c, err)
+				if config.OnExtractionError != nil {
+					config.OnExtractionError(c, err)
+				}
 			}
 			spanAttributes := ev.SpanStartAttributes()
 			if config.SpanStartAttributes != nil {
@@ -217,7 +217,9 @@ func (config Config) ToMiddleware() (echo.MiddlewareFunc, error) {
 			if err != nil {
 				span.SetAttributes(semconv.ErrorType(err))
 				span.SetStatus(codes.Error, err.Error())
-				config.OnError(c, err)
+				if config.OnNextError != nil {
+					config.OnNextError(c, err)
+				}
 			}
 
 			resp, status := echo.ResolveResponseStatus(c.Response(), err)

otel_test.go

@@ -446,21 +446,21 @@ func TestNewMiddlewareWithConfig_Metric(t *testing.T) {
 	}, sm.Metrics[0], metricdatatest.IgnoreTimestamp(), metricdatatest.IgnoreValue(), metricdatatest.IgnoreExemplars())
 }
 
-func TestWithOnError(t *testing.T) {
+func TestConfig_OnNextError(t *testing.T) {
 	tests := []struct {
 		name              string
-		GivenOnErrorFunc  OnErrorFunc
+		givenOnNextError  OnErrorFunc
 		wantHandlerCalled int
 	}{
 		{
-			name:              "without WithOnError option (default)",
-			GivenOnErrorFunc:  nil,
+			name:              "without OnNextError option (default)",
+			givenOnNextError:  nil,
 			wantHandlerCalled: 1,
 		},
 		{
-			name: "custom onError logging only",
-			GivenOnErrorFunc: func(_ *echo.Context, err error) {
-				t.Logf("Inside custom OnError: %v", err)
+			name: "custom OnNextError logging only",
+			givenOnNextError: func(_ *echo.Context, err error) {
+				t.Logf("Inside custom OnNextError: %v", err)
 			},
 			wantHandlerCalled: 1,
 		},
@@ -472,7 +472,7 @@ func TestWithOnError(t *testing.T) {
 			w := httptest.NewRecorder()
 
 			router := echo.New()
-			router.Use(NewMiddlewareWithConfig(Config{ServerName: "foobar", OnError: tt.GivenOnErrorFunc}))
+			router.Use(NewMiddlewareWithConfig(Config{ServerName: "foobar", OnNextError: tt.givenOnNextError}))
 
 			router.GET("/ping", func(_ *echo.Context) error {
 				return assert.AnError