How do I make an HTTP request from Rust?

Question

How can I make an HTTP request from Rust? I can\'t seem to find anything in the core library.

I don\'t need to parse the output, just make a request and check the HT

Answer 1

Building upon Patrik Stas' answer, if you want to do an HTTP form URL-encoded POST, here is what you have to do. In this case, it's to get an OAuth client_credentials token.

Cargo.toml

[dependencies]
reqwest = "0.10.4"
tokio = { version = "0.2.21", features = ["macros"] }

Code

use reqwest::{Client, Method};

type Error = Box<dyn std::error::Error>;
type Result<T, E = Error> = std::result::Result<T, E>;

async fn print_access_token() -> Result<()> {
    let client = Client::new();
    let host = "login.microsoftonline.com";
    let tenant = "TENANT";
    let client_id = "CLIENT_ID";
    let client_secret = "CLIENT_SECRET";
    let scope = "https://graph.microsoft.com/.default";
    let grant_type = "client_credentials";

    let url_string = format!("https://{}/{}/oauth2/v2.0/token", host, tenant);
    let body = format!(
        "client_id={}&client_secret={}&scope={}&grant_type={}",
        client_id, client_secret, scope, grant_type,
    );
    let req = client.request(Method::POST, &url_string).body(body);

    let res = req.send().await?;
    println!("{}", res.status());

    let body = res.bytes().await?;

    let v = body.to_vec();
    let s = String::from_utf8_lossy(&v);
    println!("response: {} ", s);

    Ok(())
}

#[tokio::main]
async fn main() -> Result<()> {
    print_access_token().await?;

    Ok(())
}

This will print something like the following.

200 OK
response: {"token_type":"Bearer","expires_in":3599,"ext_expires_in":3599,"access_token":"ACCESS_TOKEN"}