Frontend Logging: Integrate grafana javascript agent (#50801)

Add Grafana Javascript Agent integration to Grafana

pkg/api/frontendlogging/grafana_javascript_agent_sourcemaps.go

@@ -0,0 +1,56 @@
+package frontendlogging
+
+// ResolveSourceLocation resolves minified source location to original source location
+func ResolveSourceLocation(store *SourceMapStore, frame *Frame) (*Frame, error) {
+	smap, err := store.getSourceMap(frame.Filename)
+	if err != nil {
+		return nil, err
+	}
+	if smap == nil {
+		return nil, nil
+	}
+
+	file, function, line, col, ok := smap.consumer.Source(frame.Lineno, frame.Colno)
+	if !ok {
+		return nil, nil
+	}
+
+	// unfortunately in many cases go-sourcemap fails to determine the original function name.
+	// not a big issue as long as file, line and column are correct
+	if len(function) == 0 {
+		function = "?"
+	}
+	return &Frame{
+		Filename: file,
+		Lineno:   line,
+		Colno:    col,
+		Function: function,
+	}, nil
+}
+
+// TransformException will attempt to resolved all monified source locations in the stacktrace with original source locations
+func TransformException(ex *Exception, store *SourceMapStore) *Exception {
+	if ex.Stacktrace == nil {
+		return ex
+	}
+	frames := []Frame{}
+
+	for _, frame := range ex.Stacktrace.Frames {
+		frame := frame
+		mappedFrame, err := ResolveSourceLocation(store, &frame)
+		if err != nil {
+			frames = append(frames, frame)
+		} else if mappedFrame != nil {
+			frames = append(frames, *mappedFrame)
+		} else {
+			frames = append(frames, frame)
+		}
+	}
+
+	return &Exception{
+		Type:       ex.Type,
+		Value:      ex.Value,
+		Stacktrace: &Stacktrace{Frames: frames},
+		Timestamp:  ex.Timestamp,
+	}
+}