hapi server : when i request with POST method, hapi server responding with null, but working fine in localhost

Question

using hapi server -v = 16.7 joi -v = 10.6 deployed in aws ec2, nginx reverse proxy

Server Code in server.js:

'use strict';

//let newrelic = require('newrelic');
let Hapi = require('hapi');
let Routes = require('./Routes');
let Plugins = require('./Plugins');
let Bootstrap = require('./Utils/BootStrap');
process.env.NODE_TLS_REJECT_UNAUTHORIZED = "0";
const Inert = require('inert');
const Vision = require('vision');
const HapiSwagger = require('hapi-swagger');
const Pack = require('./package');
const Config = require('./Config');
const mongoose = require('mongoose');
mongoose.Promise = global.Promise;


const server = new Hapi.Server();



server.connection({
    port: Config.dbConfig.config.PORT,
    routes: {cors: true}
});

let mongoOpts = {
    reconnectTries: 60,
    reconnectInterval: 2000,
    useMongoClient:true
};
mongoose.connect(Config.dbConfig.config.dbURI,mongoOpts, (err, res) => {
    if (err) {
        console.log("DB Error: ", err);
        process.exit(1);
    } else {
        console.log('MongoDB Connected');
        
    }
});

server.register([
    Inert,
    Vision,
    {
        'register': HapiSwagger,
        'options': {
            info: {
                'title': Config.dbConfig.config.SWAGGERNAME,
                'version': Pack.version,
                description: '',
            },
           
            //documentationPath: '/',
            tags:[
                {
                    name: 'v2.1.0',
                    description: 'API'
                }
            ],
            grouping: 'tags',            
        },
    }], (err) => {
    server.start((err) => {
        if (err) {
            console.log("Server err----------->", err);
        } else {
            console.log('Server running at:', server.info.uri);
        }
    });
});


server.on('response', (request) => {console.log('response===>>>:');
    if(request.url.path.startsWith('/panel')){
    }
    else {//console.log('HEADERS===========>:',request.headers);
        /* console for checking the params in the request*/
        console.log(request.info.remoteAddress + ': ' + request.method.toUpperCase() +
            ' ' + request.url.path + ' --> ' + request.response.statusCode);
        console.log('Request payload:', request.payload);
    }
});

process.on('uncaughtException', function (err) {
    console.log(err);
});



server.register(Plugins, function (err) {
    if (err) {
        server.error('Error while loading plugins : ' + err)
    } else {
        server.log('info', 'Plugins Loaded')
    }
});

server.register(Inert, function (err) {
    if (err) {
        throw err;
    }
    server.route(Routes);
});

server.route([
  

    {
        method: 'GET',
        path: '/{param*}',                      /* show error page */
        handler: function (req, res) {
            res.file('./error.html')
        }
    },

    {
        path: "/panel/{path*}",
        method: "GET",
        handler: {                              /* open admin panel index from panel path*/
            directory: {
                path: ['./_admin'],
                listing: false,
                index: ['index.html']
            }
        }
    }
]);

This is deployed in AWS-EC2, with Nginx reverse proxy.When we hit POST request with payload, working fine in localhost and saves data to MongoDB. But when we hit same POST method from another domain against ec2 deployed server, the below error is showing in pm2 logs. It seems its responding with null before running the controller.

Error in pm2 logs, when we hit POST method:

TypeError: Cannot read property 'statusCode' of null
at /var/www/html/vhosts/custom_BE_ecommerce/api/server.js:123:65
at Object.internals.handler (/var/www/html/vhosts/custom_BE_ecommerce/api/node_modules/podium/lib/index.js:283:33)
at invoke (/var/www/html/vhosts/custom_BE_ecommerce/api/node_modules/podium/lib/index.js:255:23)
at each (/var/www/html/vhosts/custom_BE_ecommerce/api/node_modules/podium/lib/index.js:259:13)
at Object.exports.parallel (/var/www/html/vhosts/custom_BE_ecommerce/api/node_modules/items/lib/index.js:70:13)
at Object.internals.emit (/var/www/html/vhosts/custom_BE_ecommerce/api/node_modules/podium/lib/index.js:276:18)
at module.exports.internals.Server.internals.Podium._emit (/var/www/html/vhosts/custom_BE_ecommerce/api/node_modules/podium/lib/index.js:156:15)
at each (/var/www/html/vhosts/custom_BE_ecommerce/api/node_modules/podium/lib/index.js:197:47)
at Object.exports.parallel (/var/www/html/vhosts/custom_BE_ecommerce/api/node_modules/items/lib/index.js:70:13)
at relay (/var/www/html/vhosts/custom_BE_ecommerce/api/node_modules/podium/lib/index.js:198:15)
at Object.internals.emit (/var/www/html/vhosts/custom_BE_ecommerce/api/node_modules/podium/lib/index.js:202:16)
at internals.emitEmitter (/var/www/html/vhosts/custom_BE_ecommerce/api/node_modules/podium/lib/index.js:303:15)
at processTicksAndRejections (node:internal/process/task_queues:79:21)

Need help on this issue.

Bobby · Answer

Hello,

The issue you’re experiencing with your Hapi server deployed on AWS EC2, where POST requests are failing with a TypeError: Cannot read property 'statusCode' of null, indicates a problem in handling the response object. This issue is not present in your local environment but occurs in the production environment, which suggests a potential discrepancy between the two setups or an issue with the way the requests are handled or proxied through Nginx.

Here are some steps and considerations to debug and resolve this issue:

1. Review Nginx Reverse Proxy Configuration

Ensure that Nginx is correctly configured to proxy POST requests to your Hapi server. The configuration should include proper handling of request headers and body data.
Check if there’s any specific setting in Nginx that might be altering or blocking the payload of POST requests.
Ensure that the proxy_pass directive in Nginx is correctly pointing to the Hapi server’s address and port.

2. Inspect Application Logs

Since you’re using PM2 for process management, use PM2 logs to inspect more detailed logs of your application. This might give you more insight into what’s happening when the POST request is made.
```
pm2 logs [app-name]
```
Look for any errors or unusual entries around the time the POST requests are made.

3. Check CORS Configuration

Cross-Origin Resource Sharing (CORS) issues might arise when your frontend and backend are on different domains. Ensure your Hapi server CORS configuration is correctly set to allow requests from the domain where your frontend is hosted.

4. Verify Payload Handling

Ensure that your Hapi server is correctly parsing and handling the POST request payload. Sometimes, middleware or parsers might behave differently in production environments.

5. Test API Endpoints

Use tools like Postman or curl to manually test the API endpoints from the EC2 server. This can help you determine if the issue is with the request itself or the server’s handling of the request.
```
curl --location --request POST 'http://localhost:8000/test' --header 'Content-Type: application/json' --data-raw '{"test":"value"}'
```

Besides that, a few other things that I could suggest would be:

Check your EC2 instance’s security groups and network ACLs to ensure they allow inbound and outbound traffic on the required ports.
Review the differences between your local and production environments. Differences in Node.js versions, installed packages, or environment variables can lead to different behaviors.
Ensure that all routes and middleware in your Hapi application are properly handling exceptions. An unhandled exception might cause the response object to be null.
Consider upgrading Hapi and other dependencies to the latest stable versions if you’re using older versions. Sometimes, bugs in certain versions might cause unexpected issues.
Temporarily enable more detailed error reporting or logging in your Hapi application to get more insight into the error.

Best,

Bobby