When deploying in a subpath, the ui/agent interface returns script paths without the subpath prefix, and setting the MOUNT_PREFIX environment variable has no effect. How to solve this?

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Hello everyone,

I’ve encountered an issue when deploying a application under a subpath. Specifically, when the application is deployed behind a reverse proxy (like Nginx) under a subpath such as /subpath/, the paths for static assets (like JavaScript scripts and CSS stylesheets) referenced in the HTML page returned by the ui/agent interface do not correctly include the subpath prefix.

For example, I expect the script path to be /subpath/ui/agent/entrypoint.js, but the actual path returned in the interface is /ui/agent/entrypoint.js. This causes the browser to fail to load these resources, resulting in a blank page or a non-functional application.

I have already tried setting the MOUNT_PREFIX=/subpath environment variable, but it doesn’t seem to have any effect, and the problem persists.

Core Issue:

  • Symptom: When the ui/agent application is deployed in a subpath, the URLs for its static resources (JS/CSS) are incorrect because they are missing the subpath prefix.
  • Attempted Solution: Setting the MOUNT_PREFIX environment variable did not solve the problem.

It appears that the ui/agent interface is not reading or using the MOUNT_PREFIX environment variable.