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rustreqwest

Where does a variable passed to Reqwest's Result::read_to_string get the data from?

I am learning Rust and have been playing around with this example to perform an HTTP GET request and then display the data: 

extern crate reqwest;
use std::io::Read;

fn run() -> Result<()> {
    let mut res = reqwest::get("http://httpbin.org/get")?;
    let mut body = String::new();
    res.read_to_string(&mut body)?;

    println!("Status: {}", res.status());
    println!("Headers:\n{:#?}", res.headers());
    println!("Body:\n{}", body);

    Ok(())
}

I cannot understand how the variable body is actually ending up with the correct data. For headers and status, I can see the associated functions but for the body data it just uses read_to_string for the whole data?

Solution

  • The res object has a read_to_string() method which stores the response into the String that you pass it in

    res.read_to_string(&mut body);

    Edit: imported from my comment:

    reqwest::Response 0.6.2 documentation states for Read for Response:

    Read the body of the Response

    which somehow seems missing from the documentation of the current version.