How to use IF_INET6 - IPV6 when sending a HTTP request in Rust

Question

I am trying to send a HTTP request with IPv6.

While there are a lot of HTTP libraries (reqwest, hyper, etc). I couldn't find a library or a way to send a request with it.

In python, i was able to specify TCP family class with creating a custom TCPConnector.

import aiohttp
import socket

conn = aiohttp.TCPConnector(family=socket.AF_INET6)

I looked through the same TCPConnector, ClientBuilder things in Rust.

Reqwest's ClientBuilder doesn't supports it. See: https://docs.rs/reqwest/0.11.0/reqwest/struct.ClientBuilder.html

Hyper's HTTPConnector also doesn't supports it. See: https://docs.rs/hyper/0.14.4/hyper/client/struct.HttpConnector.html

Answer 1

It is not obvious but if you specify the local_address option, the connection will use that ip address to send the request.

I use Reqwest (v0.11.1 in the example) now.

use std::net::IpAddr;
use std::{collections::HashMap, str::FromStr};

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    let client = reqwest::Client::builder()
        .local_address(IpAddr::from_str("2001:0db8:85a3:0000:0000:8a2e:0370:7334")?) 
        .build()?;

    let resp = client
        .get("https://httpbin.org/ip")
        .send()
        .await?
        .json::<HashMap<String, String>>()
        .await?;

    println!("{:#?}", resp);
    Ok(())
}

---

This also works i but i prefer reqwest now.

Fortunately, i found a HTTP library called isahc library that i can specify IP version.

use isahc::{config::IpVersion, prelude::*, HttpClient};

HttpClient::builder()
    .ip_version(IpVersion::V6)

Isahc's isahc::HttpClientBuilder struct has ip_version method that you can specify IP version. (see)

use isahc::{config::IpVersion, prelude::*, HttpClient};
use std::{
    io::{copy, stdout},
    time::Duration,
};

fn main() -> Result<(), isahc::Error> {
    let client = HttpClient::builder()
        .timeout(Duration::from_secs(5))
        .ip_version(IpVersion::V6)
        .build()?;

    let mut response = client.get("some url")?;

    copy(response.body_mut(), &mut stdout())?;

    Ok(())
}