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.
Related
Trying to setup a staging environment on Amazon LINUX EC2 instance and migrate from Heroku.
My repository has two folders:
Web
API
Our frontend and backend are running on the same port in deployment
In dev, these are run on separate ports and all requests from WEB and proxied to API
(for ex. WEB runs on PORT 3000 and API runs on PORT 3001. Have a proxy set up in the package.json file in WEB/)
Currently the application deployment works like this:
Build Web/ for distribution
Copy build/ to API folder
Deploy to Heroku with web npm start
In prod, we only deploy API folder with the WEB build/
Current nginx.conf looks like this
Commented out all other attempts
Also using PM2 to run the thread like so
$ sudo pm2 bin/www
Current thread running like so:
pm2 log
This is running on PORT 3000 on the EC2 instance
Going to the public IPv4 DNS for instance brings me to the login, which it's getting from the /build folder but none of the login methods (or any API calls) are working.
502 response example
I have tried a lot of different configurations. Set up the proxy_pass to port 3000 since thats where the Node process is running.
The only response codes I get are 405 Not Allowed and 502 Bad Gateway
Please let me know if there is any other information I can provide to find the solution.
It looks like you don't have an upstream block in your configuration. Looks like you're trying to use proxy-pass to send to a named server and port instead of a defined upstream. There's is an example on this page that shows how you define the upstream and then send traffic to it. https://nginx.org/en/docs/http/ngx_http_upstream_module.html
server backend1.example.com weight=5;
server backend2.example.com:8080;
server unix:/tmp/backend3;
server backup1.example.com:8080 backup;
server backup2.example.com:8080 backup;
}
server {
location / {
proxy_pass http://backend;
}
}````
Turns out there was an issue with express-sessions being stored in Postgres.
This led me to retest the connection strings and I found out that I kept receiving the following error:
connect ECONNREFUSED 127.0.0.1:5432
I did have a .env file holding the env variables and they were not being read by pm2.
So I added this line to app.js:
const path = require("path");
require('dotenv').config({ path: path.join(__dirname, '.env') });
then restarted the app with pm2 with the following command:
$ pm2 restart /bin/www --update-env
I'm trying to understand what needs to be done to put my react app online.
Until now, I launched it on my mac using npm start, and accessing localhost:3000 or http://127.0.0.1:3000.
So I currently have bought a small server, installed everything (last version of node and npm, git and other necessary things), cloned my repo, and installed all dependencies.
When I do npm start on the server, it says it's available on port 3000. But when I go in my server's ip with the following :3000, it times out.
I don't really understand what need to be done to do this, I found some things about configuring apache on the server, others about using pm2 so have a node script running even after leaving the terminal, but that would be my next step I guess.. And other about configuring things with express (but do I need node+ express here ? As it's a simple front end react page ?).
if you are using webpack devserver, use it for development only
The tools in this guide are only meant for development, please avoid using them in production!
back to your question, there is a difference between binding to 127.0.0.1 or binding to 0.0.0.0
try changing the devserver to listen to 0.0.0.0
webpack.config.js
module.exports = {
//...
devServer: {
host: '0.0.0.0'
}
};
Usage via the CLI
webpack-dev-server --host 0.0.0.0
also note, that you will need to allow ingress rules (incoming connections). that is, allow a request from the internet to reach your server
There are a lot of configurations you will have to do when you deploy your application on a server. Building the app, Nginx, pm2 and even ssl certification. This video is 20min and has all you need. https://www.youtube.com/watch?v=oykl1Ih9pMg&t=1s
Trying to get Simple Express Application up using NameCheap Shared Hosting.
I have set up my Node JS application as Described here NodeJS NameCheap Docs
Current Setup:
Application Root: url.com
Application URL: url.com
Application Startup File: server.js
I have ran NPM Install using the button provided
I have tried loading the URL http://url.com/hello Expecting Hello World to displayed in the Page.
var express = require("express");
var app = express();
const port = 3001;
app.set("port", port);
app.get("/hello", function(req, res) {
res.send("hello world");
});
app.listen(app.get("port"), () =>
console.log("Started listening on %s", app.get("port"))
);
The results I am getting when navigating to http://url.com/hello:
Not Found
The requested URL /index.php was not found on this server.
Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request.
Namecheap only tells you how to configure the nodejs app however their hosting is based on cPanel which requires you configure the webserver (apache generally). Once you get an application running there’s a special button to register it for the apache configuration aka let it run from your domain. I don’t know the steps by heart but you should ask NC support to direct you to their documentation for configuring apache to run a nodejs app you configured.
If they do not link an article from their knowledge base use this link: https://confluence1.cpanel.net/plugins/servlet/mobile?contentId=17190639#content/view/17190639
Basically what you need now is to configure cPanel or ssh into your server and test your app locally. There’s a number of things that could cause your issues like incorrect apache configuration (your default port 80 is looking for php app), port not open/firewalled, application not registered - and all of this is cPanel specific.
To make sure you are reading the correct document check in namecheap cpanel for the docs button and review all the above. It should be obvious what needs configured - your nodejs code is probably not the cause here
In my case, it was the problem with .htaccess file. Adding the following rules in my .htaccess file present in the website's public directory helped me:
# CLOUDLINUX PASSENGER CONFIGURATION BEGIN
PassengerAppRoot "/home/<user>/<your_nodejs_app_folder>"
PassengerBaseURI "/."
PassengerNodejs "/home/<user>/nodevenv/<nodejs_app>/<version>/bin/node"
PassengerAppType node
PassengerStartupFile <startup_script>.js
# CLOUDLINUX PASSENGER CONFIGURATION END
Make the required changes in the above rules before pasting them in your .htaccess file. Also, just in case, make sure the port you are using is open, via customer support.
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'm using the Wercker Continuous Integration & Delivery Platform to test and deploy a BitBucket repository on a node.js OpenShift server. Wercker loads in the BitBucket repository, builds it, tests it in the node.js environment, and passes it without any issue. It's also checking the code with jsHint, and returns without any errors.
Wercker also indicates that the deployment passes without errors, as does OpenShift. The problem is that when I check the application URL provided to me by OpenShift, it results with a server error:
503 Service Temporarily Unavailable
The server is temporarily unable to service your request due to maintenance downtime or capacity problems. Please try again later.
In troubleshooting this, I restarted the server (I'm running the basic account, and I have that option) but that doesn't seem to resolve the issue. Neither Wercker or Openshift indicate that there is a problem, but for some reason, I'm simply unable to access that domain without error.
How can I fix this (with the most basic tier)?
This was the solution:
I installed the RHC client tools available on the OpenShift website, checked the application logs, and found that OpenShift was unable to find a server.js file in the root directory. So I renamed my app.js file to server.js, and in my package.json I changed the "start" value to server.js. Then I configured the code in server.js file to the OpenShift environment variables, and that did it!
The server.js now reads:
var http = require('http');
var ip = process.env.OPENSHIFT_NODEJS_IP || '127.0.0.1',
port = process.env.OPENSHIFT_NODEJS_PORT || '8080';
http.createServer(function (req, res) {
res.writeHead(200, {'Content-Type': 'text/plain'});
res.end('Hello World\n');
}).listen(port, ip);
console.log('Server running at http://'+ip+':'+port+'/');
I'm now able to connect to the application URL and get the basic "Hello World" response.
(If at this point you're still unable to connect to your application, restart your server, and that should do the trick.)
I hope this helps someone else in the future.
Here's a helpful resource that I leaned on: https://gist.github.com/ryanj/5267357
Your app should be able to listen to the IP and port defined by Openshift's reverse proxy.
You need to change the port number and perhaps the IP in the server configuration.
Explained here: OpenShift node.js Error: listen EACCES