trail

Documentation

Overview

Package trail integrates trace errors with GRPC

Example server that sends the GRPC error and attaches metadata:

func (s *server) Echo(ctx context.Context, message *gw.StringMessage) (*gw.StringMessage, error) {
	trace.SetDebug(true) // to tell trace to start attaching metadata
	// Send sends metadata via grpc header and converts error to GRPC compatible one
	return nil, trail.Send(ctx, trace.AccessDenied("missing authorization"))
}

Example client reading error and trace debug info:

var header metadata.MD
r, err := c.Echo(context.Background(), &gw.StringMessage{Value: message}, grpc.Header(&header))
if err != nil {
	// FromGRPC reads error, converts it back to trace error and attaches debug metadata
	// like stack trace of the error origin back to the error
	err = trail.FromGRPC(err, header)

	// this line will log original trace of the error
	log.Errorf("error saying echo: %v", trace.DebugReport(err))
	return
}

Index

• func FromGRPC(err error, args ...interface{}) error
• func ToGRPC(originalErr error) error

Functions

func FromGRPC

func FromGRPC(err error, args ...interface{}) error

FromGRPC converts error from GRPC error back to trace.Error Debug information will be retrieved from the metadata if specified in args

func ToGRPC

func ToGRPC(originalErr error) error

ToGRPC converts error to GRPC-compatible error