Function DefaultHTTPErrorHandler

echo.go:431–479

DefaultHTTPErrorHandler creates new default HTTP error handler implementation. It sends a JSON response with status code. `exposeError` parameter decides if returned message will contain also error message or not Note: DefaultHTTPErrorHandler does not log errors. Use middleware for it if errors nee

(exposeError bool)

// handler. Then the error that global error handler received will be ignored because we have already "committed" the
// response and status code header has been sent to the client.
func DefaultHTTPErrorHandler(exposeError bool) HTTPErrorHandler {
	return func(c *Context, err error) {
		if r, _ := UnwrapResponse(c.response); r != nil && r.Committed {
			return
		}

		code := http.StatusInternalServerError
		var sc HTTPStatusCoder
		if errors.As(err, &sc) {
			if tmp := sc.StatusCode(); tmp != 0 {
				code = tmp
			}
		}

		var result any
		switch m := sc.(type) {
		case json.Marshaler: // this type knows how to format itself to JSON
			result = m
		case *HTTPError:
			sText := m.Message
			if sText == "" {
				sText = http.StatusText(code)
			}
			msg := map[string]any{"message": sText}
			if exposeError {
				if wrappedErr := m.Unwrap(); wrappedErr != nil {
					msg["error"] = wrappedErr.Error()
				}
			}
			result = msg
		default:
			msg := map[string]any{"message": http.StatusText(code)}
			if exposeError {
				msg["error"] = err.Error()
			}
			result = msg
		}

		var cErr error
		if c.Request().Method == http.MethodHead { // Issue #608
			cErr = c.NoContent(code)
		} else {
			cErr = c.JSON(code, result)
		}
		if cErr != nil {
			c.Logger().Error("echo default error handler failed to send error to client", "error", cErr) // truly rare case. ala client already disconnected
		}
	}
}

// Pre adds middleware to the chain which is run before router tries to find matching route.
// Meaning middleware is executed even for 404 (not found) cases.