// SafelyCallUnaryHandler calls the handler h, recovering panics and timeout errors,
// converting them to yarpc errors. All other errors are passed trough.
func SafelyCallUnaryHandler(
ctx context.Context,
h transport.UnaryHandler, start time.Time,
req *transport.Request,
resq transport.ResponseWriter,
) (err error) {
// We recover panics from now on.
defer func() {
if r := recover(); r != nil {
log.Printf("Unary handler panicked: %v\n%s", r, debug.Stack())
err = fmt.Errorf("panic: %v", r)
}
}()
err = h.Handle(ctx, req, resq)
// The handler stopped work on context deadline.
if err == context.DeadlineExceeded && err == ctx.Err() {
deadline, _ := ctx.Deadline()
err = errors.HandlerTimeoutError(req.Caller, req.Service,
req.Procedure, deadline.Sub(start))
}
return err
}
func (c *countInterceptor) Handle(
ctx context.Context, req *transport.Request, resw transport.ResponseWriter, h transport.UnaryHandler) error {
c.Count++
return h.Handle(ctx, req, resw)
}
func (requestLogInterceptor) Handle(ctx context.Context, req *transport.Request, resw transport.ResponseWriter, handler transport.UnaryHandler) error {
fmt.Printf("received a request to %q from client %q (encoding %q)\n",
req.Procedure, req.Caller, req.Encoding)
return handler.Handle(ctx, req, resw)
}