System proxy seems doesn't work.

[ramsayleung]

Hi Sean, thanks for your hard work, you build an awesome Http client. I have encountered a problem when I used system proxy with reqwest. The document claims reqwest doesn't need the explict system proxy setting, system proxies are enabled by default:

System proxies look in environment variables to set HTTP or HTTPS proxies.

HTTP_PROXY or http_proxy provide http proxies for http connections while HTTPS_PROXY or https_proxy provide HTTPS proxies for HTTPS connections.

What I struggle with is that I have explictly set the system proxy setting with:

export HTTPS_PROXY=socks5://127.0.0.1:2085

but reqwest still goes without proxy.

This is my code:

use std::env;
extern crate log;

fn main() -> Result<(), Box<dyn std::error::Error>> {
    env_logger::init();
    match env::var("HTTPS_PROXY") {
        Ok(proxy) => println!("proxy: {}", proxy),
        Err(e) => println!("Couldn't read HTTPS_PROXY ({})", e),
    };
    let client = reqwest::blocking::Client::builder()
        .connection_verbose(true)
        .build()?;
    let mut res = client.get("https://httpbin.org/ip").send()?;
    // copy the response body directly to stdout
    res.copy_to(&mut std::io::stdout())?;
    Ok(())
}

This is the output:

$ RUST_LOG=reqwest=debug cargo run
   Compiling reqwest-test v0.1.0 (/private/tmp/reqwest-test)
    Finished dev [unoptimized + debuginfo] target(s) in 3.74s
     Running `target/debug/reqwest-test`
proxy: socks5://127.0.0.1:2085
[2020-01-19T08:05:15Z DEBUG reqwest::async_impl::response] Response: '200 OK' for https://httpbin.org/ip
{
  "origin": "ip1, ip2" // this is definitely not the ip of my proxy server
}

Do I do something wrong or miss something? I can't figure out why couldn't reqwest work with system proxy.

[WindSoilder]

What I remember is that system proxy only support http scheme and https scheme for now. Others will be omitted..

[seanmonstar]

Oh ya, we probably need to add the socks support to the system proxy code.

[ramsayleung]

Before I submit this issue, I have searched all issues of reqwest, I remember reqwest is supporting socks proxy now, #287, or reqwest supports both socks proxy and system proxy, but the system proxy doesn't support socks proxy?

[WindSoilder]

I found that reqwest can use socks through http_proxy or https_proxy variable in my environment, sorry for yesterday's misleading information :(

I have seen your PR in rspotify, to use socks proxy, socks feature is required.

reqwest = { version = "0.10", features = ["blocking", "json", "socks"] }

[ramsayleung]

Wow, it works now, I just simply omit this feature when I go through the document, thanks so much for pointing it out :)

[seanmonstar]

Ah, is there something we could have done to make that clearer? Do the proxy docs mention the socks feature? Should we log that socks was ignored since the feature wasn't enabled?

[WindSoilder]

I think it's good enough to doc them in the lib :)

[ramsayleung]

You guys do a great job to make reqwest better :)