A Beginner Guide to Rust HTTP Client Libraries

This repository contains an example of how to use HTTP client libraries in Rust.

We will start with low level library called Hyper and move up with high-level library called reqwest.

So, let's start with GET request.

GET Request

Below is an example code on how to perform HTTP GET request using the hyper library

extern crate hyper;

use hyper::body::HttpBody as _;
use hyper::Client;
use tokio::io::{stdout, AsyncWriteExt as _};

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error + Send + Sync>> {
    // This is where we will setup our HTTP client requests.
    println!("Hello?");

    // Still inside `async fn main`...
    let client = Client::new();

    // Parse an `http::Uri`...
    let uri = "http://httpbin.org/ip".parse()?;

    // Await the response...
    let mut resp = client.get(uri).await?;

    println!("Response: {}", resp.status());

    // And now...
    while let Some(chunk) = resp.body_mut().data().await {
        stdout().write_all(&chunk?).await?;
    }

    Ok(())
}

Maybe you are beginner like me and have the following questions:

1. What is #[tokio::main] ? Why is there?
2. Why returns Result<(), Box<dyn std::error::Error + Send + Sync>> ?

See you next time.