如何使用Node.js 10x在AWS Lambda中将发布请求发送到外部api？

Question

I am trying to send post request to an external api in aws lambda using nodejs 10.x. But I am getting error

Response:
{
  "errorMessage": "Converting circular structure to JSON",
  "errorType": "TypeError",
  "stackTrace": []
}

Please find the code below:

const http = require('https');

exports.handler = async (event) => {
    return new Promise((resolve, reject) => {

        const req = http.request('https://jsonplaceholder.typicode.com/posts', (res) => {
            resolve(res);
        });

        req.on('error', (e) => {
          reject({error: e.message});
        });

        // send the request
        req.write('');
        req.end();
    });
};

I am expecting json response like below

[
  {
    "userId": 1,
    "id": 1,
    "title": "sunt aut facere repellat provident occaecati excepturi optio reprehenderit",
    "body": "quia et suscipit\nsuscipit recusandae consequuntur expedita et cum\nreprehenderit molestiae ut ut quas totam\nnostrum rerum est autem sunt rem eveniet architecto"
  },
  {
    "userId": 1,
    "id": 2,
    "title": "qui est esse",
    "body": "est rerum tempore vitae\nsequi sint nihil reprehenderit dolor beatae ea dolores neque\nfugiat blanditiis voluptate porro vel nihil molestiae ut reiciendis\nqui aperiam non debitis possimus qui neque nisi nulla"
  }
]

Answer 1

You are using http.request without adding options object but a URL. You should replace it with http.get or add options object.

You are also resolving response from http request without building the data. If you are using Lambda behind API Gateway proxy integration then response should be formatted. Following code should work.

const http = require('https');

let getData = () => {

  return new Promise((resolve, reject) => {

    http.get('https://jsonplaceholder.typicode.com/posts', (resp) => {

      let data = '';

      resp.on('data', (chunk) => {
        data += chunk;
      });

      resp.on('end', () => {
        resolve(data);
      });
    }).on('error', (e) => {
      console.log('Error', e.message);
      reject(e);
    });
  });
};

module.exports.handler = async (event) => {

  try {
    // Data is string.
    const data = await getData();
    return {
      statusCode: 200,
      body: data
    }
  }
  catch (e) {
    console.log(e);
    return {
      statusCode: 400,
      body: e.message
    }
  }
};