[API] Null result from API.post() or (put)

[shide1989]

Describe the bug
I'm using aws-amplify API to call the Rest API I've setup using Amplify,
but the return value is always null

It used to work fine using the Lambda Hello World template, but switching to the lambda express template made this happen.

Inspecting the request shows that the result returned from the API is a correct JSON value , but once received the Amplify SDK seems to mess things up and remove the data.

The same happens for the .put() method

I suspect that deploying the new Lambda, some headers might be missing or some parameters might be missing, that makes the data decoding impossible

To Reproduce
Steps to reproduce the behavior:

1. Create a Amplify Rest API
2. Create a Cognito UserPool Authentication
3. Create a Lambda based on the express-lambda template
4. Add an API Rest endpoint that triggers the Lambda you created and authorises authenticated users only
5. Use the API from the aws-amplify package, and make a request
6. The result is null

Expected behavior
We should be able to see the data returned from the request.

Code Snippet

import { API } from 'aws-amplify'

const myFunction = async () => {
  const result = await API.post('esportsverify', '/conversations', {
      body: { username: other }
    })
// result is null -_-
}

Screenshots

What is Configured?
If applicable, please provide what is configured for Amplify CLI:

• Resources configured
  const awsmobile = {
  "aws_project_region": "eu-west-1",
  "aws_appsync_graphqlEndpoint": "https://xxxxxxxxxxxx.appsync-api.eu-west-1.amazonaws.com/graphql",
  "aws_appsync_region": "eu-west-x",
  "aws_appsync_authenticationType": "API_KEY",
  "aws_appsync_apiKey": "xxxxxx-xxxxxxxxxx",
  "aws_cloud_logic_custom": [
  {
  "name": "esportsverify",
  "endpoint": "https://xxxxxxx.execute-api.eu-west-1.amazonaws.com/develop",
  "region": "eu-west-x"
  }
  ],
  "aws_content_delivery_bucket": "xxxxxx-xxxxxx-xxxxxxx-hostingbucket-develop",
  "aws_content_delivery_bucket_region": "eu-west-1",
  "aws_content_delivery_url": "https://xxxxx.cloudfront.net",
  "aws_cognito_identity_pool_id": "eu-west-1:xxxxxx-xxxxx-xxxx-xxxxx-xxxxxx",
  "aws_cognito_region": "eu-west-1",
  "aws_user_pools_id": "eu-west-xxxxxx",
  "aws_user_pools_web_client_id": "xxxxxxxxxx",
  "oauth": {},
  "aws_dynamodb_all_tables_region": "eu-west-1",
  "aws_dynamodb_table_schemas": [
  {
  "tableName": "xxxxxx-develop",
  "region": "eu-west-1"
  },
  {
  "tableName": "xxxxxxxx-develop",
  "region": "eu-west-1"
  }
  ]
  };

Environment

npx envinfo --system --binaries --browsers --npmPackages --npmGlobalPackages



  System:
    OS: macOS Mojave 10.14.6
    CPU: (8) x64 Intel(R) Core(TM) i7-7700HQ CPU @ 2.80GHz
    Memory: 353.45 MB / 16.00 GB
    Shell: 5.3 - /bin/zsh
  Binaries:
    Node: 12.16.1 - ~/.nvm/versions/node/v12.16.1/bin/node
    npm: 6.14.4 - ~/.nvm/versions/node/v12.16.1/bin/npm
  Browsers:
    Chrome: 80.0.3987.149
    Firefox Developer Edition: 77.0
    Safari: 13.1
  npmPackages:
    @aws-amplify/auth: ^3.2.4 => 3.2.4 
    @reach/router: ^1.3.3 => 1.3.3 
    aws-amplify: ^3.0.13 => 3.0.13 
    aws-amplify-react: ^3.1.1 => 3.1.9 
    bootstrap: ^4.4.1 => 4.4.1 
    clipboard: ^2.0.4 => 2.0.4 
    eslint-config-react-app: ^5.1.0 => 5.1.0 
    gatsby: 2.20.36 => 2.20.36 
    gatsby-image: ^2.2.36 => 2.2.36 
    gatsby-plugin-exclude: ^1.0.2 => 1.0.2 
    gatsby-plugin-google-analytics: ^2.3.1 => 2.3.1 
    gatsby-plugin-manifest: ^2.3.3 => 2.3.3 
    gatsby-plugin-offline: ^3.0.29 => 3.0.29 
    gatsby-plugin-react-helmet: ^3.1.18 => 3.1.18 
    gatsby-plugin-react-svg: ^3.0.0 => 3.0.0 
    gatsby-plugin-resolve-src: ^2.0.0 => 2.0.0 
    gatsby-plugin-sass: ^2.1.26 => 2.1.26 
    gatsby-plugin-sharp: ^2.5.3 => 2.5.3 
    gatsby-source-filesystem: ^2.1.42 => 2.1.42 
    gatsby-source-graphql: ^2.1.28 => 2.1.28 
    gatsby-transformer-sharp: ^2.4.3 => 2.4.3 
    husky: ^3.1.0 => 3.1.0 
    moment: ^2.24.0 => 2.24.0 
    node-sass: ^4.13.1 => 4.13.1 
    prettier: ^1.19.1 => 1.19.1 
    prop-types: ^15.7.2 => 15.7.2 
    react: ^16.12.0 => 16.12.0 
    react-bootstrap: ^1.0.0-beta.16 => 1.0.0 
    react-device-detect: ^1.11.14 => 1.11.14 
    react-dom: ^16.12.0 => 16.12.0 
    react-helmet: ^5.2.1 => 5.2.1 
    react-infinite-scroll-component: ^5.0.4 => 5.0.4 
    slug: ^2.1.0 => 2.1.0 
    talkjs: ^0.14.1 => 0.14.1 
    use-deep-compare-effect: ^1.3.0 => 1.3.0 
  npmGlobalPackages:
    @aws-amplify/cli: 4.19.0
    @ionic/cli: 6.8.0
    @types/express: 4.17.6
    @types/googlemaps: 3.39.3
    @types/node: 13.13.4
    @types/places: 1.16.0
    @types/react: 16.9.34
    @types/request: 2.48.4
    @vue/cli: 4.3.1
    amplify: 0.0.11
    aws-amplify: 3.0.10
    aws-cli: 0.0.2
    aws-sdk: 2.666.0
    cordova-res: 0.14.0
    eslint: 6.8.0
    lumber-cli: 3.5.6
    npm-check-updates: 6.0.1
    npm: 6.14.4
    pm2: 4.4.0
    spaceship-zsh-theme: 2.11.0
    typings: 2.1.1

You can turn on the debug mode to provide more info for us by setting window.LOG_LEVEL = 'DEBUG'; in your app.
-> Done but it doesn't show anything

[shide1989]

One of my guesses, is that it's linked to this issue : CodeGenieApp/serverless-express#99

[shide1989]

I think it's definitively linked to this issue, since the body returned by the API is encoded in base64. It seems to me that Axios or the RestClient class (used by amplify) is unable to decode the base64 string

[cedricgrothues]

Hey @shide1989, I tried to recreate your issue, but unfortunately, I wasn't able to reproduce it using the default aws-serverless-express lambda template.

I added important parts of my project below. Please let me know if there anything I am missing.

// aws-exports.js

const awsmobile = {
    "aws_project_region": "eu-central-1",
    "aws_cognito_identity_pool_id": "eu-central-1:xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx",
    "aws_cognito_region": "eu-central-1",
    "aws_user_pools_id": "eu-central-1_xxxxxxxxx",
    "aws_user_pools_web_client_id": "xxxxxxxxxxxxxxxxxxxxxxxxxxxx",
    "oauth": {},
    "aws_cloud_logic_custom": [
        {
            "name": "apid6e5a88b",
            "endpoint": "https://xxxxxxxxxx.execute-api.eu-central-1.amazonaws.com/dev",
            "region": "eu-central-1"
        }
    ]
};

API.post('apid6e5a88b', '/conversations', {
	body: { username: 'other' },
})
.then(r => console.log({ response: r }));

// console.log output
{
    response: {
        body: {
            username: "other"
        },
        success: "post call succeed!",
        url: "/conversations"
    }
}

// lambda function: index.js
const awsServerlessExpress = require('aws-serverless-express');
const app = require('./app');

const server = awsServerlessExpress.createServer(app);

exports.handler = (event, context) => {
  console.log(`EVENT: ${JSON.stringify(event)}`);
  return awsServerlessExpress.proxy(server, event, context, 'PROMISE').promise;
};

// lambda function: app.js
var express = require('express')
var bodyParser = require('body-parser')
var awsServerlessExpressMiddleware = require('aws-serverless-express/middleware')

var app = express()
app.use(bodyParser.json())
app.use(awsServerlessExpressMiddleware.eventContext())

app.use(function(req, res, next) {
  res.header("Access-Control-Allow-Origin", "*")
  res.header("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept")
  next()
});

// ...

app.post('/conversations', function(req, res) {
  res.json({success: 'post call succeed!', url: req.url, body: req.body})
});

// ...

app.put('/conversations', function(req, res) {
  res.json({success: 'put call succeed!', url: req.url, body: req.body})
});

// ...

app.listen(3000, function() {
    console.log("App started")
});

module.exports = app

[stale]

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