public void onError(final String phase, final String errorCode) {
                    try {
                        sendSseEvent(writer, "error", Map.of("phase", phase, "message", errorCode, "errorCode", errorCode));
                        if (logger.isDebugEnabled()) {
                            logger.debug("SSE error event sent. phase={}, error={}", phase, errorCode);
                        }

                    logger.warn("Failed to access Web API.", e);
                }
                message = e.getMessage();
            } else {
                final String errorCode = UUID.randomUUID().toString();
                message = "[" + errorCode + "] Failed to access to Web API.";
                if (statusCode >= 400 && statusCode < 500) {
                    if (logger.isDebugEnabled()) {

            var errorMessage = config.labels.error;
            try {
                var data = JSON.parse(e.data);
                if (data.errorCode && config.labels.errors && config.labels.errors[data.errorCode]) {
                    errorMessage = config.labels.errors[data.errorCode];
                } else if (data.message) {
                    errorMessage = data.message;
                }
            } catch (ex) {}

      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
  schemas:
    Error:
      type: object
      properties:
        error_code:
          type: string
          example: "bd6b0bd6-0144-40bc-9567-c5751dd8eecb"
        message:
          type: string
          example: "This is an error message."