amazon-web-services - 如何通过无服务器框架响应准确的错误状态代码和消息？

Question

我通过以下命令创建了无服务器框架的功能：

sls function create some/api

然后创建了 schelton 代码：

'use strict';

module.exports.handler = function(event, context, cb) {
  return cb({
    message: 'Go Serverless! Your Lambda function executed successfully!'
  });
};

并且，响应模板如下：

s-function.json

  "responses": {
    "400": {
      "statusCode": "400"
    },
    "default": {
      "statusCode": "200",
      "responseParameters": {},
      "responseModels": {
        "application/json;charset=UTF-8": "Empty"
      },
      "responseTemplates": {
        "application/json;charset=UTF-8": ""
      }
    }
  }

但是，当我将错误对象返回给回调函数时cb(err, null)，错误消息正确显示，但 statusCode 为 200。

如果我改为调用回调函数cb("400", err)，则 statusCode 正确返回 400，但响应体不好：{"errorMessage":"400"}。

有没有什么好的设置来显示机器人状态码（不仅是 400，还有 401,403,404,500...等等）和错误消息？

Answer 1

我使用以下响应模板。如果从 lambda 函数返回的消息与selectionPattern响应模板中指定的匹配，它将返回正确的状态码。

"responseTemplate": {
    "400": {
        "selectionPattern": "^\\[BadRequest\\].*",
        "statusCode": "400"
    },
    "401": {
        "selectionPattern": "^\\[Unauthorized\\].*",
        "statusCode": "401"
    },
    "403": {
        "selectionPattern": "^\\[Forbidden\\].*",
        "statusCode": "403"
    },
    "404": {
        "selectionPattern": "^\\[NotFound\\].*",
        "statusCode": "404"
    },
    "409": {
        "selectionPattern": "^\\[Conflict\\].*",
        "statusCode": "409"
    },
    "500": {
        "selectionPattern": "^\\[Process exited|ServerError\\].*",
        "statusCode": "500"
    },
    "504": {
        "selectionPattern": "^\\[Task timed out\\].*",
        "statusCode": "504"
    },
    "default": {
        "statusCode": "200",
        "responseParameters": {},
        "responseModels": {},
        "responseTemplates": {
            "application/json": ""
        }
    }
}