feat: add FrameMatcher config option (#23)

This allows to remove any kind of frame from the stacktrace sent to Sentry e.g. if zap is used in combination with go-logr.

config.go

@@ -45,4 +45,8 @@ type Configuration struct {
 	// Hub overrides the sentry.CurrentHub value.
 	// See sentry.Hub docs for more detail.
 	Hub *sentry.Hub
+
+	// FrameMatcher allows to ignore some frames of the stack trace.
+	// this is particularly useful when you want to ignore for instances frames from convenience wrappers
+	FrameMatcher FrameMatcher
 }

core.go

@@ -18,7 +18,49 @@ const (
 	zapSentryScopeKey = "_zapsentry_scope_"
 )
 
-var ErrInvalidBreadcrumbLevel = errors.New("breadcrumb level must be lower than or equal to error level")
+var (
+	ErrInvalidBreadcrumbLevel = errors.New("breadcrumb level must be lower than or equal to error level")
+
+	defaultFrameMatchers = FrameMatchers{
+		SkipModulePrefixFrameMatcher("github.com/TheZeroSlave/zapsentry"),
+		SkipFunctionPrefixFrameMatcher("go.uber.org/zap"),
+	}
+)
+
+type (
+	FrameMatcher interface {
+		Matches(f sentry.Frame) bool
+	}
+	FrameMatchers                  []FrameMatcher
+	FrameMatcherFunc               func(f sentry.Frame) bool
+	SkipModulePrefixFrameMatcher   string
+	SkipFunctionPrefixFrameMatcher string
+)
+
+func (f FrameMatcherFunc) Matches(frame sentry.Frame) bool {
+	return f(frame)
+}
+
+func (f SkipModulePrefixFrameMatcher) Matches(frame sentry.Frame) bool {
+	return strings.HasPrefix(frame.Module, string(f))
+}
+
+func (f SkipFunctionPrefixFrameMatcher) Matches(frame sentry.Frame) bool {
+	return strings.HasPrefix(frame.Function, string(f))
+}
+
+func (ff FrameMatchers) Matches(frame sentry.Frame) bool {
+	for i := range ff {
+		if ff[i].Matches(frame) {
+			return true
+		}
+	}
+	return false
+}
+
+func CombineFrameMatchers(matcher ...FrameMatcher) FrameMatcher {
+	return FrameMatchers(matcher)
+}
 
 func NewScopeFromScope(scope *sentry.Scope) zapcore.Field {
 	f := zap.Skip()
@@ -46,6 +88,20 @@ func NewCore(cfg Configuration, factory SentryClientFactory) (zapcore.Core, erro
 		cfg.MaxBreadcrumbs = defaultMaxBreadcrumbs
 	}
 
+	// copy default values to avoid accidental modification
+	matchers := make(FrameMatchers, len(defaultFrameMatchers), len(defaultFrameMatchers)+1)
+	copy(matchers, defaultFrameMatchers)
+
+	switch m := cfg.FrameMatcher.(type) {
+	case nil:
+		cfg.FrameMatcher = matchers
+	case FrameMatchers:
+		// in case the configured matcher was already a collection, append the default ones to avoid nested looping
+		cfg.FrameMatcher = append(matchers, m...)
+	default:
+		cfg.FrameMatcher = append(matchers, cfg.FrameMatcher)
+	}
+
 	core := core{
 		client: client,
 		cfg:    &cfg,
@@ -125,7 +181,7 @@ func (c *core) Write(ent zapcore.Entry, fs []zapcore.Field) error {
 		if event.Exception == nil && !c.cfg.DisableStacktrace && c.client.Options().AttachStacktrace {
 			stacktrace := sentry.NewStacktrace()
 			if stacktrace != nil {
-				stacktrace.Frames = filterFrames(stacktrace.Frames)
+				stacktrace.Frames = c.filterFrames(stacktrace.Frames)
 				event.Threads = []sentry.Thread{{Stacktrace: stacktrace, Current: true}}
 			}
 		}
@@ -166,7 +222,7 @@ func (c *core) createExceptions() []sentry.Exception {
 	if !c.cfg.DisableStacktrace && exceptions[0].Stacktrace == nil {
 		stacktrace := sentry.NewStacktrace()
 		if stacktrace != nil {
-			stacktrace.Frames = filterFrames(stacktrace.Frames)
+			stacktrace.Frames = c.filterFrames(stacktrace.Frames)
 			exceptions[0].Stacktrace = stacktrace
 		}
 	}
@@ -314,33 +370,34 @@ type core struct {
 	fields map[string]interface{}
 }
 
-type LevelEnabler struct {
-	zapcore.LevelEnabler
-	enableBreadcrumbs bool
-	breadcrumbsLevel  zapcore.LevelEnabler
-}
-
-func (l *LevelEnabler) Enabled(lvl zapcore.Level) bool {
-	return l.LevelEnabler.Enabled(lvl) || (l.enableBreadcrumbs && l.breadcrumbsLevel.Enabled(lvl))
-}
-
 // follow same logic with sentry-go to filter unnecessary frames
 // ref:
 // https://github.com/getsentry/sentry-go/blob/362a80dcc41f9ad11c8df556104db3efa27a419e/stacktrace.go#L256-L280
-func filterFrames(frames []sentry.Frame) []sentry.Frame {
+func (c *core) filterFrames(frames []sentry.Frame) []sentry.Frame {
 	if len(frames) == 0 {
 		return nil
 	}
 
-	for i := range frames {
-		// Skip zapsentry and zap internal frames, except for frames in _test packages (for
-		// testing).
-		if (strings.HasPrefix(frames[i].Module, "github.com/TheZeroSlave/zapsentry") ||
-			strings.HasPrefix(frames[i].Function, "go.uber.org/zap")) &&
-			!strings.HasSuffix(frames[i].Module, "_test") {
-			return frames[0:i]
+	for i := 0; i < len(frames); {
+		if c.cfg.FrameMatcher.Matches(frames[i]) {
+			if i < len(frames)-1 {
+				copy(frames[i:], frames[i+1:])
+			}
+			frames = frames[:len(frames)-1]
+			continue
 		}
+		i++
 	}
 
 	return frames
 }
+
+type LevelEnabler struct {
+	zapcore.LevelEnabler
+	enableBreadcrumbs bool
+	breadcrumbsLevel  zapcore.LevelEnabler
+}
+
+func (l *LevelEnabler) Enabled(lvl zapcore.Level) bool {
+	return l.LevelEnabler.Enabled(lvl) || (l.enableBreadcrumbs && l.breadcrumbsLevel.Enabled(lvl))
+}

core_test.go

@@ -0,0 +1,93 @@
+package zapsentry
+
+import (
+	"strings"
+	"testing"
+
+	"github.com/getsentry/sentry-go"
+)
+
+func Test_core_filterFrames(t *testing.T) {
+	t.Parallel()
+	type args struct {
+		frames []sentry.Frame
+	}
+	tests := []struct {
+		name                string
+		matcher             FrameMatcher
+		args                args
+		wantRemainingFrames int
+	}{
+		{
+			name:    "Empty filter set - do not filter anything at all",
+			matcher: FrameMatchers{},
+			args: args{
+				[]sentry.Frame{
+					{
+						Module: "github.com/TheZeroSlave/zapsentry",
+					},
+				},
+			},
+			wantRemainingFrames: 1,
+		},
+		{
+			name:    "Default filter set - filter frames from zapsentry",
+			matcher: defaultFrameMatchers,
+			args: args{
+				[]sentry.Frame{
+					{
+						Module: "github.com/TheZeroSlave/zapsentry",
+					},
+					{
+						Module: "github.com/TheZeroSlave/zapsentry/someinternal",
+					},
+				},
+			},
+			wantRemainingFrames: 0,
+		},
+		{
+			name:    "Default filter set - filter frames from zap",
+			matcher: defaultFrameMatchers,
+			args: args{
+				[]sentry.Frame{
+					{
+						Function: "go.uber.org/zap/String",
+					},
+				},
+			},
+			wantRemainingFrames: 0,
+		},
+		{
+			name: "Custom filter - ignore if test file",
+			matcher: FrameMatcherFunc(func(f sentry.Frame) bool {
+				return strings.HasSuffix(f.Filename, "_test.go")
+			}),
+			args: args{
+				[]sentry.Frame{
+					{
+						Filename: "core_test.go",
+					},
+					{
+						Filename: "core.go",
+					},
+				},
+			},
+			wantRemainingFrames: 1,
+		},
+	}
+	for _, tt := range tests {
+		tt := tt
+		t.Run(tt.name, func(t *testing.T) {
+			t.Parallel()
+			c := &core{
+				cfg: &Configuration{
+					FrameMatcher: tt.matcher,
+				},
+			}
+			got := c.filterFrames(tt.args.frames)
+			if len(got) != tt.wantRemainingFrames {
+				t.Errorf("filterFrames() = %v, want %v", got, tt.wantRemainingFrames)
+			}
+		})
+	}
+}

example_logger_test.go

@@ -29,12 +29,17 @@ func ExampleAttachCoreToLogger() {
 
 	// Setup zapsentry
 	core, err := zapsentry.NewCore(zapsentry.Configuration{
-		Level: zapcore.ErrorLevel, // when to send message to sentry
-		EnableBreadcrumbs: true, // enable sending breadcrumbs to Sentry
-		BreadcrumbLevel: zapcore.InfoLevel, // at what level should we sent breadcrumbs to sentry
+		Level:             zapcore.ErrorLevel, // when to send message to sentry
+		EnableBreadcrumbs: true,               // enable sending breadcrumbs to Sentry
+		BreadcrumbLevel:   zapcore.InfoLevel,  // at what level should we sent breadcrumbs to sentry
 		Tags: map[string]string{
 			"component": "system",
 		},
+		FrameMatcher: zapsentry.CombineFrameMatchers(
+			// skip all frames having a prefix of 'go.uber.org/zap'
+			// this can be used to exclude e.g. logging adapters from the stacktrace
+			zapsentry.SkipFunctionPrefixFrameMatcher("go.uber.org/zap"),
+		),
 	}, zapsentry.NewSentryClientFromClient(sentryClient))
 	if err != nil {
 		log.Fatal(err)
@@ -59,8 +64,8 @@ func ExampleAttachCoreToLogger() {
 
 func mockSentryClient(f func(event *sentry.Event)) *sentry.Client {
 	client, _ := sentry.NewClient(sentry.ClientOptions{
-		Dsn:              "",
-		Transport:        &transport{MockSendEvent: f},
+		Dsn:       "",
+		Transport: &transport{MockSendEvent: f},
 	})
 	return client
 }