如何在 firebase 函数上获取传入的 sendgrid 电子邮件

Question

我有一个 firebase 函数，我将其用作 sendgrid 的入站解析 webhook 的 webhook。因此，这意味着无论何时向我的域发送电子邮件，它都会调用 webhook。我知道正在调用 webhook，但我无法获取 Sendgrid 发送的数据。 This link 声明所有信息（文本、发件人等）都应该在 headers 中。但是，当我打印出 req.headers 时，我得到了这个：

{ host: 'us-central1-project-name.cloudfunctions.net',
  'user-agent': 'Sendlib/1.0 server.sendgrid.net',
  'transfer-encoding': 'chunked',
  'content-type': 'multipart/form-data; boundary=xYzZY',
  forwarded: 'for="ip";proto=https',
  'function-execution-id': 'id',
  'x-appengine-city': '?',
  'x-appengine-citylatlong': '0.000000,0.000000',
  'x-appengine-country': 'US',
  'x-appengine-default-version-hostname': ~~~~~~~~~~~~~.appspot.com',
  'x-appengine-https': 'on',
  'x-appengine-region': '?',
  'x-appengine-request-log-id': 'super-long-id',
  'x-appengine-user-ip': 'ip',
  'x-cloud-trace-context': 'id/number;o=1',
  'x-forwarded-for': 'ip',
  'x-forwarded-proto': 'https',
  'accept-encoding': 'gzip',
  connection: 'close' }'

（显然我替换了所有 ID 和所有内容）

电子邮件信息在哪里？我已尝试执行以下所有操作，其中 none 生成了有关电子邮件的任何信息。

exports.reciever = functions.https.onRequest((req, res) => {
  try {
   console.log("Email recieved");
   console.log(req);
   console.log(req.headers);
   console.log(req.header.to);
   console.log(req.body);
   console.log(req.get('to'));
   console.log(req.body.to);
   console.log(req.rawBody);
   console.log(req.query);
   console.log(req.query.to);
   console.log(req.params);
   console.log(req.path);
   console.log(req.rawBody);
  } catch (e) {}
  finally {
      res.send("2xx");
  } 
})

Answer 1

所以，事实证明它其实非常非常简单。添加

.toString()

在 req.body 或 req.rawBody 对象的末尾。

Answer 2

该问题是关于在无服务器环境（AWS Lambda、Firebase/Google Cloud Functions 等）和已处理请求的环境中使用。使用 MIME 解析电子邮件不是一个好主意。因此，这是我的解决方案：

import * as functions from 'firebase-functions';
import * as express from 'express';
const formidable = require('formidable-serverless');

export class InboundEmail {
  constructor(from, subject, text, html, to) {}
  doStrategy() {
     //Store inbound email
     //Send outbound email
     //...
  }
}

export class EmailPostWebHook {
  private form = new formidable.IncomingForm();
  private incomeEmail: IncomeEmail;

  async run(request: express.Request, res: express.Response) {
    try {
      this.parse(request);
      await this.incomeEmail.doStrategy();
    } catch (e) {
      console.log(e);
    }
    return res.sendStatus(200);
  }

  private parse(request: express.Request) {
    this.form.parse(request, (errors: any, fields: any) => {
      this.incomeEmail = new IncomeEmail(
        fields.from
        fields.subject,
        fiels.text
        fields.html,
        fields.to
      );
    });
  }
}


const app = express();

const emailPostWebHook = new EmailPostWebHook();
app.post('/', emailPostWebHook.run.bind(emailPostWebHook));

export const InboundEmailHook = functions
  .runWith({
    timeoutSeconds: 30,
    memory: '2GB',
  })
  .https.onRequest(app);

package.json

{
  "name": "temp",
  "main": "lib/index.js",
  "dependencies": {
    "express": "^4.17.1",
    "firebase": "^7.15.1",
    "firebase-admin": "^8.12.1",
    "firebase-functions": "^3.7.0",
    "formidable-serverless": "^1.0.3"
  },
  "devDependencies": {
    "@firebase/firestore-types": "^1.11.0",
    "@types/node": "^14.0.13",
    "@types/express": "^4.17.6",
    "tslint": "^6.1.2",
    "typescript": "^3.9.5"
  },
  "engines": {
    "node": "10"
  },
  "private": true
}

参考文献：

https://github.com/sendgrid/sendgrid-nodejs/blob/master/docs/examples/webhooks-docker/routes/inbound-parse.js

https://github.com/Amit-A/formidable-serverless/

https://www.npmjs.com/package/formidable

Answer 3

我终于设法通过在 functions-directory 中安装 Busboy 然后使用此处提供的代码来让它工作：

如何在 firebase 函数上获取传入的 sendgrid 电子邮件

How to get incoming sendgrid email on firebase functions

http-post

node.js

sendgrid

firebase

google-cloud-functions