Set environment variable VSCODE_PROXY_URI

[benz0li]

With the implementation of the HTTP proxy it would be great to have an environment variable VSCODE_HTTP_REFERER available to build custon URLs for proxied webview requests.

This feature helps solving REditorSupport/vscode-R#275. The existence of such an environment variable also allows to differentiate a local (VS Code) installation from a server (code-server) installation.

Other server-based IDEs set an environment variable based on the HTTP referer when the client session is initialized. See https://github.com/rstudio/rstudio/blob/aa266ded96123f654e5f3163cde39697744eee89/src/cpp/session/SessionClientInit.cpp#L170 for example.

Could you implement something similar in code-server? Or is the information on the HTTP referer already available somewhere else?

[kylecarbs]

Neat. I don't think we have this ATM.

Thoughts @code-asher ?

[code-asher]

I experimented with replacing 127.0.0.1:<port> with /proxy/<port> before writing out the webview HTML which worked for the PlatformIO extension but then it tried to make a websocket connection against the root (/wsrpc) instead of being relative (/path/<port>/wsrpc) which obviously won't work.

So the environment variable sounds like a reasonable way to solve this. Either that or require that extensions be aware that they might be behind a proxied base path and make connections accordingly. There might be other cases I haven't considered though so the environment variable seems like the most flexible.

[code-asher]

We should also make this environment variable available to the terminal (in addition to extensions), see #1939.

[benz0li]

@code-asher Any timeframe on this issue? Does the name tend towards VSCODE_HTTP_REFERER or CODE_SERVER_HTTP_REFERER?

The project collaborators at Ikuyadeu/vscode-R might give another go at REditorSupport/vscode-R#275 while working on REditorSupport/vscode-R#358.

[code-asher]

We don't have this on the roadmap at the moment but it seems pretty trivial to implement so I think we could reasonably have it for 3.11.0.

[code-asher]

Oh right the name. I think `CODE_SERVER_HTTP_REFERER` makes sense.

[benz0li]

Oh right the name. I think CODE_SERVER_HTTP_REFERER makes sense.

@code-asher Keeping in mind other derivatives of VS Code (e.g. Eclipse Theia) it would make sense to tend towards VSCODE_HTTP_REFERER.
👉 The name of their ancestor; a common name to implement the functionality for Ikuyadeu/vscode-R in all of VS Code derivatives - if their collaborators decide to do so.

Agreed?

[benz0li]

Alternaively HTTP_REFERER; neutral, not mentioning a product name.

[code-asher]

That makes perfect sense to me! My vote would be for HTTP_REFERER I think but I'm good with either one.