I have looked at similar questions and not been able to solve this problem with what I found. I initially followed a YouTube tutorial on how to deploy a Node.js App to Heroku. After trying and failing, I began troubleshooting and could not fix the problem.
I then followed the instructions on Heroku's website for deploying a Node.js application here: https://devcenter.heroku.com/articles/deploying-nodejs and I found I seem to have done all the steps correctly. I was just missing the node version in the package.json which I have now added.
Here is how I have connected my Node.js app:
image of Heroku application dashboard
And here is the connected Github repo: https://github.com/AmeenIzhac/food-and-flow-backend
You can see in the repo that my port is specified correctly:
const port = process.env.PORT || 4000;
I then tried running the app locally on the command line with:
heroku local web
and this worked as you can see my application running on port 5000:
App running locally on port 5000
However when I press "Open app" in Heroku, I just see this:
Heroku hosted app fails to get /
I feel like I have done everything correctly but it doesn't seem to work. Any help to get it working would be much appreciated.
You need a procfile. What is the heroku error in heroku logs --tail?
I'm looking a solution for my stupid problems.
I use Heroku to deployed my application. After I linked to github,I got this error when open my application:
Application error An error occurred in the application and your page
could not be served. If you are the application owner, check your logs
for details. You can do this from the Heroku CLI with the command
heroku logs --tail
I tried to research the solution but nothing worked.
My config in app.js
port = process.env.PORT || config.__port_server,
app.listen(port)
thank you
I'm trying to deploy a PeerJS server on Azure. On my kudu console, running
node peerjs --port 9000
returns
Started PeerServer on ::, port: 9000, path: / (v. 0.2.8)
However, when I try to connect to the server from my client code, I get a 404. Going directly to appname.azurewebsites.net/peerjs/id in my browser also returns a 404.
I see inside their package.json file, they run
bin/peerjs --port ${PORT:=9000}
instead of just passing in 9000 directly; I assume this is an environment variable. However, trying to run this on Azure gives
Error: Error: listen EACCES ${PORT:=9000}
which I assume means Azure doesn't recognize ${PORT:=9000} as a valid port.
I know for a fact there's nothing wrong with my client side code because a) I copied it directly from PeerJS's website, and b) everything works correctly when I deployed PeerJS to Heroku. It's only not running on Azure.
Other things I've tried: I edited peerjs in the bin folder to use process.env.PORT instead of what's passed in via the command line, but that didn't work, giving the same EACCES error. When I tried to console.log(process.env.PORT), I got undefined. None of my Google searches have turned up any solutions, although this person (Custom PeerJs Server giving ERR_CONNECTION_TIMED_OUT) seems to have a similar error, not on Azure.
Azure App Service doesn't allow us to listen on a customer port. We need to use process.env.PORT instead. See Listen additional port Microsoft Azure Nodejs.
Azure App Service (on Windows platform) runs on Microsoft IIS. So we need to put the app files to its virtual directory (D:\home\site\wwwroot) and no longer need to manually run the app via the Kudu console.
In this case, you first need to install the library under app's root:
npm install peer
And then create a file named index.js or app.js with following content and put it to /wwwroot folder:
var PeerServer = require('peer').PeerServer;
var server = PeerServer({port: process.env.PORT, path: '/'});
As #Mikkel mentioned in a comment, PeerServer uses WebSocket protocol, so Web Sockets should be enabled in the Azure portal like this:
You also need to check out this post to add a web.config file for your app if it has not been created yet.
This will be a firewall problem... You will need to open port 9000 in your Azure settings panel.
From the machine itself, open up a browser to http://localhost:9000/ or http://localhost:9000/peerjs and you should see the standard Peerjs server JSON output.
Or if you only have command line, try curl http://localhost:9000/ or http://localhost:9000/peerjs
I am hosting the web app on Google Cloud Platform with App Engine and I am using ExpressJS and MongoDB, which is hosted on mLab.
Everything worked well until 1/1/2017. I had vm:true before and now was forced to change the env to flex. Now I am getting 502 bad gateway error with nginx. App engine doesn't allow us to change the nginx config file.
I had tried the suggestion from this post: Google App Engine 502 (Bad Gateway) with NodeJS but still doesn't work.
For some reason, I have another app with exactly the same setting on app engine and it works perfectly.
Any suggestion will be greatly appreciated. Thank you.
app should always listen to port 8080, google forwards all request from 80 to 8080
https://cloud.google.com/appengine/docs/flexible/custom-runtimes/build#listen_to_port_8080
check out the logs for any deployment errors
$ gcloud app logs read
I have came across a similar issue with the code provided by this tutorial (https://cloud.google.com/nodejs/getting-started/authenticate-users)
And found there was a missing dependency. I fixed the missing dependency and the app is deployed and working fine.
Details into the issue: https://github.com/GoogleCloudPlatform/nodejs-getting-started/issues/106
I had the same problem with Express. What solved it for me was to not provide an IP address for the app.
So my old code would be:
var ip = "127.0.0.1";
var port = "8080";
var server = http.createServer(app);
server.listen(port, ip);
This would result in a 502 in app engine.
Removing the ip was the solution for me.
server.listen(port);
Set the host to 0.0.0.0
Port 8080 is set by default by the engine. In fact, you are not able to define the environment var PORT as it is reserved.
Run the next command (as mentioned by #sravan )
gcloud app logs read tail
and make sure it looks like this,
[Sun May 27 2018 10:32:44 GMT+0000 (UTC)] serving app on 0.0.0.0:8080
Cheers
Google App Engine uses an nginx front to load balance all requests for node.js apps. With nginx acting as a forward proxy, this error usually happens when the request the user is making in the browser is reaching nginx (you see the unstyled 502 bad gateway error page) but the nginx server is not able to correctly forward the request to your node app. There could be many issues why this is happening but here are some common ones:
By default, App Engine assumes your node app is running on 8080. nginx itself will run on 80 and forward the request to 8080. Check if your app's port number is 8080.
You app may have a hostname defined like a domain something.appspot.com or an IP 127.18.21.21 or the like. Remove any hostnames from your server.listen or config.json or vhost wherever. App Engine will take care of domains, IPs etc so you dont have to.
Your app may be crashing before its sending a response to nginx. Check the logs of both nginx AND your node app.
To check logs / find out what is going on use this guide https://cloud.google.com/appengine/docs/flexible/nodejs/debugging-an-instance#connecting_to_the_instance to SSH directly inside the VM behind app engine. There will be one docker process with nginx where you can see the nginx error log and one docker image with your node app to check your node app's error message.
I'm just wondering, based on the activity in this question and the timestamps, why hasn't Google updated its documentation to cover this issue!!! ???
Please take care of http also, while deploying, it should be http server not https
var server;
if (process.env.NODE_ENV == "dev") {
server = https.createServer(httpsOptions, app);
} else {
server = http.createServer(app);
}
A 502 is not necessarily an error with nginx itself, it can most often happen when the nginx proxy cannot talk to your app container (usually because your app failed to start). If you get a 502 after migrating to 'env: flex' this is most likely due to some code changes needed in your app as mentioned in Upgrading to the Latest App Engine Flexible Environment Release.
Checking your application logs for errors from NPM will also help to diagnose the exact reason for the failed startup.
Create a server and then check with a ternary condition if current environment is production or not, assign port '80' if current environment is development else assign process.env.NODE.ENV.
const app = require('express')();
const server = require('http').Server(app);
const port = process.env.NODE_ENV === 'production' ? process.env.PORT :'80';
server.listen(port, ()=> {
console.log('listening on port number *:' + server.address().port);
});
In my case, I had the same error due to google app engine update which trigged auto re-deployment of my React SPA to the google cloud vm. Then it leads to a build fail in the process because of incompatibility of runtime which is node 16.x.x. Compatible runtime was node 14.19.0. I had to specify node version in my package.json file and do the deployment again to fix 502 Bad Gateway error.
{
"engines": {
"node": "14.19.0"
}
}
Also refer:
https://cloud.google.com/appengine/docs/nodejs
https://cloud.google.com/appengine/docs/flexible/nodejs/runtime
Hope this helps with someone having this issue with React SPAs.
We have a REST API (npm restify) to deploy to Azure and it was successful.
After this we have the web.config pointing it to the app.js in the root (was server.js as stock). Looking at the logs it says pointing to 0.0.0.0 on port 8085. We are not sure how to change this as we have env variables set to change these but Azure kudu doesnt seem to listen.
The app.js is also just a module.exports = require(".src/server.js"); Any thoughts would be much appreciated!
Turns out it was the env variables. We had BLAH_BLAH_PORT when it should have been just PORT