WebSockets with Railway

Hi there! So Im doing a game using websockets. Frontend is using react.js and backend is using java with maven.

We have the server up and runing without issues. But we cant seem to get our ports to match, it just says that we fail to connect for exampel port 8080.

We have tried to copy the domain from the backend with :8080 to the frontend.

e929f490-a8af-4200-97d4-e6e331581ff3

your websocket server should run on host 0.0.0.0 and the auto generated PORT (not 8080)
your react frontend will then connect over wss without specifying any port

Hi Brody, We will try it

Should there still be wss://0.0.0.0 ?

wss://<whatever your railway domain is>/<whatever your websocket endpoint is>

So it would be wss://backend-production-6ad2.up.railway.app/

The domain would be from our backend (java) Railway app

if the root endpoint / handles websocket connections and not something like /ws then yes that is correct

For the record, we recommend adding a custom domain for websockets

Railway proxy does terminate sessions after 30 seconds for scale reasons on *.up.railway.app domains

We have now tried to remove the port from our websocket server, So the constructor for the jetty websockets get nothing. And the Procfile gets just PORT. And we still have the issue.

Going to need some logs my guy

We have a custom domain for the future

Sure thing!

Backend Deploy logs:

2023-05-24 19:56:43.320:INFO::main: Logging initialized @2009ms to org.eclipse.jetty.util.log.StdErrLog

2023-05-24 19:56:43.466:INFO:oejs.Server:main: jetty-9.4.9.v20180320; built: 2018-03-20T12:21:10Z; git: 1f8159b1e4a42d3f79997021ea1609f2fbac6de5; jvm 17.0.5+8-nixos

2023-05-24 19:56:43.705:INFO:oejs.Server:main: Started @2402ms

is maven listening on host 0.0.0.0 and the environment variable PORT

This would be our maven POM:

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>

<groupId>groupId</groupId>
<artifactId>backend</artifactId>
<version>1.0-SNAPSHOT</version>



<build>



<plugins>

<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-dependency-plugin</artifactId>
<version>2.4</version>
<executions>
<execution>
<phase>package</phase>
<goals><goal>copy</goal></goals>
<configuration>
<artifactItems>
<artifactItem>
<groupId>org.eclipse.jetty</groupId>
<artifactId>jetty-runner</artifactId>
<version>9.4.9.v20180320</version>
<destFileName>jetty-runner.jar</destFileName>
</artifactItem>
</artifactItems>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</build>

<properties>
<maven.compiler.source>1.8</maven.compiler.source>
<maven.compiler.target>1.8</maven.compiler.target>
</properties>

<dependencies>
<dependency>
<groupId>org.eclipse.jetty</groupId>
<artifactId>jetty-server</artifactId>
<version>9.4.44.v20210927</version>
</dependency>
<dependency>
<groupId>org.eclipse.jetty.websocket</groupId>
<artifactId>websocket-server</artifactId>
<version>9.4.44.v20210927</version>
</dependency>
<dependency>
<groupId>org.eclipse.jetty.websocket</groupId>
<artifactId>websocket-servlet</artifactId>
<version>9.4.44.v20210927</version>
</dependency>
<dependency>
<groupId>com.google.code.gson</groupId>
<artifactId>gson</artifactId>
<version>2.8.9</version>
</dependency>
</dependencies>



</project>

Btw I are really sorry I come across as stupid, but I am very new to hosting services and websockets

^

How would I look for if maven i listening for 0.0.0.0 and the variable port?

PORT***

i wouldnt know, ive never touched java in my life, i just know once you get maven to listen on host 0.0.0.0 and environment variable PORT it should work

so, read the documentation for maven? stack overflow, etc

Alright no worries! Last dumb question then, is the environment variable PORT in railway and what you recommend having it as?

Im guessing it should look something like this but with a acutall port in it:

you shoulnt be setting the PORT yourself if you can avoid it, and especially not in shared variables

the environment variable PORT is one railway generates for you, no need to define it yourself

Yep this is likely it

Copy that!

This what I came up with when using maven:

<httpConnector>
<host>0.0.0.0</host>
<port>${PORT}</port>
</httpConnector>

Still trying to get the environment variable PORT to work

find out how you can get maven to grab the PORT variable from the enviroment