preview links dont work for `localhost` ports

[lukeed]

Describe the bug

For a localhost port, Daytona serves a 502 Bad Gateway error indefinitely while polling. Can confirm that the port is up and running (via netstat or ss -lt).

This continues indefinitely until the server is exposed to the network (eg 0.0.0.0). When this happens, I now get a vite error saying that the incoming *.daytona.work domain isnt allowed to access the dev server.

Blocked request. This host ("[id].[hash].daytona.work") is not allowed.
To allow this host, add "[id].[hash].daytona.work" to `server.allowedHosts` in vite.config.js.

To Reproduce
Steps to reproduce the behavior:

1. Create a workspace with any vite starter app
2. yarn dev inside workspace
3. Get preview link for 5173 -> 502 error
4. run yarn dev --host to expose over network
5. Get preview link for 5173 -> 403 error

Expected behavior
Preview link(s) for a target port should be working regardless of interface.

[Tpuljak]

@lukeed we had a discussion about this and decided not to work around this with our proxy. It's behavior we noticed with a lot of other services (e.g. VS Code, Github Codespaces) and we believe that with the proper docs, users can be informed how to configure Vite (and similar services) to work.

That being said, we'll keep this issue open until we address this properly in our docs.

[lukeed]

Sorry I think thats kinda silly. The whole point of a preview link is to tunnel into the workspace. If its only for public ports, then you dont need the API to issue a preview link at all (aside from providing a token, for private workspaces) because its a standard format that I can just construct myself.

The token should be required for private sandboxes and for "private"/local ports.

[Tpuljak]

@lukeed we took a closer look at this and discussed more, taking into account your last comment.

We agree with you. As part of this issue, we'll refactor our proxy to allow accessing services started on localhost.
I'll update you as we work through this.

[lukeed]

Awesome, thanks!