Crate reqwest

reqwest

The reqwest crate provides a convenient, higher-level HTTP Client.

It handles many of the things that most people just expect an HTTP client to do for them.

• Uses system-native TLS
• Plain bodies, JSON, urlencoded, multipart
• Customizable redirect policy
• Proxies
• (TODO: Cookies)

The reqwest::Client is synchronous, making it a great fit for applications that only require a few HTTP requests, and wish to handle them synchronously.

Making a GET request

For a single request, you can use the get shortcut method.

use std::io::Read;

let mut resp = reqwest::get("https://www.rust-lang.org")?;
assert!(resp.status().is_success());

let mut content = String::new();
resp.read_to_string(&mut content);

As you can see, reqwest's Response struct implements Rust's Read trait, so many useful standard library and third party crates will have convenience methods that take a Response anywhere T: Read is acceptable.

If you plan to perform multiple requests, it is best to create a Client and reuse it, taking advantage of keep-alive connection pooling.

Making POST requests (or setting request bodies)

There are several ways you can set the body of a request. The basic one is by using the body() method of a RequestBuilder. This lets you set the exact raw bytes of what the body should be. It accepts various types, including String, Vec<u8>, and File. If you wish to pass a custom Reader, you can use the reqwest::Body::new() constructor.

let client = reqwest::Client::new();
let res = client.post("http://httpbin.org/post")
    .body("the exact body that is sent")
    .send()?;

Forms

It's very common to want to send form data in a request body. This can be done with any type that can be serialized into form data.

This can be an array of tuples, or a HashMap, or a custom type that implements Serialize.

// This will POST a body of `foo=bar&baz=quux`
let params = [("foo", "bar"), ("baz", "quux")];
let client = reqwest::Client::new();
let res = client.post("http://httpbin.org/post")
    .form(&params)
    .send()?;

JSON

There is also a json method helper on the RequestBuilder that works in a similar fashion the form method. It can take any value that can be serialized into JSON.

// This will POST a body of `{"lang":"rust","body":"json"}`
let mut map = HashMap::new();
map.insert("lang", "rust");
map.insert("body", "json");

let client = reqwest::Client::new();
let res = client.post("http://httpbin.org/post")
    .json(&map)
    .send()?;

Modules

header	Headers container, and common header fields.
mime
multipart
unstable	A set of unstable functionality.

Structs

Body	The body of a Request.
Certificate	Represent an X509 certificate.
Client	A Client to make Requests with.
ClientBuilder	A ClientBuilder can be used to create a Client with custom configuration.
Error	The Errors that may occur when processing a Request.
Identity	Represent a private key and X509 cert as a client certificate.
Proxy	Configuration of a proxy that a Client should pass requests to.
RedirectAction	An action to perform when a redirect status code is found.
RedirectAttempt	A type that holds information on the next request and previous requests in redirect chain.
RedirectPolicy	A type that controls the policy on how to handle the following of redirects.
Request	A request which can be executed with Client::execute().
RequestBuilder	A builder to construct the properties of a Request.
Response	A Response to a submitted Request.
Url	A parsed URL record.

Enums

Method	The Request Method (VERB)
StatusCode	An HTTP status code (status-code in RFC 7230 et al.).
UrlError	Errors that can occur during parsing.

Traits

IntoUrl

A trait to try to convert some type into a Url.

Functions

get	Shortcut method to quickly make a GET request.

Type Definitions

Result

A Result alias where the Err case is reqwest::Error.