AWS-serverless-express 从不通过承诺解决

Posted 2023-03-07

【中文标题】AWS-serverless-express 从不通过承诺解决

【英文标题】：AWS-serverless-express never resolving with promises

【发布时间】：2020-06-29 23:01:46

【问题描述】：

谁能阐明我在 github 上的 aws-serverless-express 存储库中打开的问题？ https://github.com/awslabs/aws-serverless-express/issues/276

我正在尝试使用 aws-serverless-express 包运行我以前的 express.js 服务器。当我在没有任何特殊选项的情况下运行时，我解决了，但链中的承诺永远不会得到尊重，这意味着我不会在事件循环中执行所有事情。

如果我使用“PROMISE”标志运行 serverlessexpress，我会执行我的所有承诺，但程序永远不会解析并在设置的最长时间后超时。

我什至按照该仓库中的示例启动了一个新项目，结果相同。

解决但不遵守我的承诺时我的主要执行文件（index.js）

const awsServerlessExpress = require('aws-serverless-express')
const app = require('./app.js')
const server = awsServerlessExpress.createServer(app, null)

exports.handler = (event, context) => 
  return awsServerlessExpress.proxy(server, event, context)

我的主要执行文件 (index.js) 未解决，但尊重我的承诺

const awsServerlessExpress = require('aws-serverless-express')
const app = require('./app.js')
const server = awsServerlessExpress.createServer(app, null)

exports.handler = (event, context) => 
  return awsServerlessExpress.proxy(server, event, context, 'PROMISE')

我也试过这个：

const awsServerlessExpress = require('aws-serverless-express')
const app = require('./app.js')
const server = awsServerlessExpress.createServer(app, null)

exports.handler = (event, context) => 
  return awsServerlessExpress.proxy(server, event, context, 'PROMISE').promise

我的快递服务器文件（app.js）

const express = require('express')
const bodyParser = require('body-parser')
const awsServerlessExpressMiddleware = require('aws-serverless-express/middleware')
const app = express()
const router = express.Router()

router.use(bodyParser.json())
router.use(bodyParser.urlencoded( extended: true ))
router.use(awsServerlessExpressMiddleware.eventContext())

router.get('/', (req, res) => 
  res.render('index', 
    apiUrl: req.apiGateway ? `https://$req.apiGateway.event.headers.Host/$req.apiGateway.event.requestContext.stage` : 'http://localhost:3000'
  )
)

router.get('/users', (req, res) => 
  res.json(users)
)

const users = [
  id: 1,
  name: 'Joe'
, 
  id: 2,
  name: 'Jane'
]

function myFunc () 
  console.log('hey')

setTimeout(myFunc, 3000)

app.use('/', router)

module.exports = app

【问题讨论】：

This Github issue comment 会建议它是 awsServerlessExpress.proxy(server, event, context, 'PROMISE').promise 而不是 awsServerlessExpress.proxy(server, event, context, 'PROMISE') 这可能会起作用。线程中的下一条评论还提出了另一种解决方案 - 我希望它有所帮助。

@cubrr 我也试过了，结果一样。

【参考方案1】：

问题与我的测试工具有关：

https://www.npmjs.com/package/run-local-lambda

当我与 AWS Support 交谈时，他们告诉我使用：

sam local invoke "Test" -e event.json

使用包含以下内容的 event.json 文件：

    "httpMethod": "OPTIONS",
    "//body": "\"name\": \"Sam\"",
    "path": "/api/auth",
    "resource": "/proxy+",
    "queryStringParameters": ,
    "pathParameters": 
        "proxy": "users"
    ,
    "headers": 
        "Accept": "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8",
        "Accept-Encoding": "gzip, deflate, sdch, br",
        "Accept-Language": "en-US,en;q=0.8",
        "CloudFront-Forwarded-Proto": "https",
        "CloudFront-Is-Desktop-Viewer": "true",
        "CloudFront-Is-Mobile-Viewer": "false",
        "CloudFront-Is-SmartTV-Viewer": "false",
        "CloudFront-Is-Tablet-Viewer": "false",
        "CloudFront-Viewer-Country": "US",
        "Content-Type": "application/json",
        "Host": "xxxxxxxxxx.execute-api.us-east-1.amazonaws.com",
        "Upgrade-Insecure-Requests": "1",
        "User-Agent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/52.0.2743.116 Safari/537.36",
        "Via": "1.1 xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx.cloudfront.net (CloudFront)",
        "X-Amz-Cf-Id": "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx_xxxxxxxxxxx_xxxx==",
        "X-Forwarded-For": "11.111.111.111, 11.111.111.111",
        "X-Forwarded-Port": "111",
        "X-Forwarded-Proto": "http",
        "x-apigateway-event": "hej"

    ,
    "requestContext": 
        "accountId": "111111111111",
        "resourceId": "xxxxxx",
        "stage": "prod",
        "requestId": "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx",
        "identity": 
            "cognitoIdentityPoolId": "",
            "accountId": "",
            "cognitoIdentityId": "",
            "caller": "",
            "apiKey": "",
            "sourceIp": "11.111.111.111",
            "cognitoAuthenticationType": "",
            "cognitoAuthenticationProvider": "",
            "userArn": "",
            "userAgent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/52.0.2743.116 Safari/537.36",
            "user": ""
        ,
        "resourcePath": "/proxy+",
        "httpMethod": "GET",
        "apiId": "xxxxxxxxxx"
    

还有一个仅用于测试的模板文件，如下所示：

AWSTemplateFormatVersion : '2010-09-09'
Transform: AWS::Serverless-2016-10-31

Description:
 A test project

Resources:
 Test:
  Type: AWS::Serverless::Function
  Properties:
   Runtime: nodejs10.x
   Handler: index.handler
   Timeout: 10
   Environment:
     Variables:
       NODE_ENV: "test"
       DB_NAME: "dbname"
       DB_USER: "dbuser"
       DB_PASSWORD: "secret"
       DB_URL: "dburl"

我在处理程序中使用的代码如下所示：

'use strict'
const awsServerlessExpress = require('aws-serverless-express')
const app = require('./main.js')

const server = awsServerlessExpress.createServer(app, null)    
exports.handler = (event, context) => 
  return awsServerlessExpress.proxy(server, event, context,'PROMISE').promise

然后我的代码执行得非常好，从来没有超时。

【参考方案2】：

确保将 context.callbackWaitsForEmptyEventLoop 设置为 false

在此处阅读更多信息https://docs.aws.amazon.com/lambda/latest/dg/nodejs-context.html