Support ALL_PROXY environment variable

[kidonng]

Quoting Everything curl:

To set a single variable that controls all protocols, the ALL_PROXY exists. If a specific protocol variable one exists, such a one will take precedence.

I (and possibly most people) set HTTP_PROXY and HTTPS_PROXY to be the same anyway, so supporting ALL_PROXY in addition to them seems reasonable.

[benesch]

If you need something that supports this today: https://docs.rs/mz-http-proxy/latest/mz_http_proxy/

[kidonng]

Thanks, but I realized this is something more application-specific. Most programs supporting it are using (lib)curl under the hood, and curl has it because it supports tons of protocol, while others are only dealing http(s) and maybe socks(5).

[benesch]

I’m not sure I follow. You can use mz_http_proxy::reqwest::client to get a reqwest client in Deno that’s configured to respect ALL_PROXY and the other proxy env vars. It’s the same reqwest under the hood, just configured to look at the proxy env vars that it otherwise wouldn’t.

It’s not just cURL that supports ALL_PROXY; there’s pretty good support for it across networking stacks in a lot of languages, e.g.: https://pkg.go.dev/golang.org/x/net/proxy#FromEnvironment

[Revanee]

This issue should be closed since it was resolved by #1856