Method FireErrorCode

core/router/handler.go:544–652

FireErrorCode handles the response's error response. If `Configuration.ResetOnFireErrorCode()` is true and the response writer was a recorder one then it will try to reset the headers and the body before calling the registered (or default) error handler for that error code set by `ctx.StatusCode` me

(ctx *context.Context)

// registered (or default) error handler for that error code set by
// `ctx.StatusCode` method.
func (h *routerHandler) FireErrorCode(ctx *context.Context) {
	// On common response writer, always check
	// if we can't reset the body and the body has been filled
	// which means that the status code already sent,
	// then do not fire this custom error code,
	// rel: context/context.go#EndRequest.
	//
	// Note that, this is set to 0 on recorder because it holds the response before sent,
	// so we check their len(Body()) instead, look below.
	if ctx.ResponseWriter().Written() > 0 {
		return
	}

	statusCode := ctx.GetStatusCode() // the response's cached one.

	if ctx.Application().ConfigurationReadOnly().GetResetOnFireErrorCode() /* could be an argument too but we must not break the method */ {
		// if we can reset the body, probably manual call of `Application.FireErrorCode`.
		if w, ok := ctx.IsRecording(); ok {
			if statusCodeSuccessful(w.StatusCode()) { // if not an error status code
				w.WriteHeader(statusCode) // then set it manually here, otherwise it should be set via ctx.StatusCode(...)
			}
			// reset if previous content and it's recorder, keep the status code.
			w.ClearHeaders()
			w.ResetBody()

			if cw, ok := w.ResponseWriter.(*context.CompressResponseWriter); ok {
				// recorder wraps a compress writer.
				cw.Disabled = true
			}
		} else if w, ok := ctx.ResponseWriter().(*context.CompressResponseWriter); ok {
			// reset and disable the gzip in order to be an expected form of http error result
			w.Disabled = true
		}
	} else {
		// check if a body already set (the error response is handled by the handler itself,
		// see `Context.EndRequest`)
		if w, ok := ctx.IsRecording(); ok {
			if len(w.Body()) > 0 {
				return
			}
		}
	}

	for i := range h.errorTrees {
		t := h.errorTrees[i]

		if statusCode != t.statusCode {
			continue
		}

		if h.errorHosts && !canHandleSubdomain(ctx, t.subdomain) {
			continue
		}

		n := t.search(ctx.Path(), ctx.Params())
		if n == nil {
			// try to take the root's one.
			n = t.root.getChild(pathSep)