Question
Set app platform HTTP port without overwriting PORT variable
- Posted on May 15, 2025
- App Platform
Asked by Mike
The application I’m using uses the PORT variable for something else than the main listening port.
Why does setting the service’s HTTP port set the PORT environment variable and how can I avoid this? It seems completely absurd to force overwrite the PORT env variable. It makes my app unusable with the app platform.
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Hi there,
As far as I know, there’s no way to prevent this behavior right now. App Platform assumes your app will listen on whatever is in
PORT, and it injects that value at runtime to manage routing.If your app uses
PORTfor something else, one workaround is to modify your app (if possible) to read the actual listening port from another variable, likeAPP_PORT, and map that manually in your code.It’s worth reaching out to support to confirm if there’s any way around this: https://do.co/support
And might be a good idea to suggest it as a feature here too: https://ideas.digitalocean.com/
- Bobby