如何使用 Reqwest 设置请求 headers？

Question

我需要使用 Reqwest 库向带有 cookie 的网站发出 GET 请求。我想出了如何发送 GET 请求：

let response = reqwest::get("http://example.com")?;

如何发送相同的请求但添加一些自定义 headers？

Answer 1

要求 0.10

从 crate's documentation 开始，我们看到：

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

get's documentation 状态：

This function creates a new internal Client on each call, and so should not be used if making many requests. Create a Client instead.

Client 有一个 request 方法，它指出：

Returns a RequestBuilder, which will allow setting headers and request body before sending.

RequestBuilder 有一个 header method。这可以用作：

use reqwest::header::USER_AGENT;

let client = reqwest::Client::new();
let res = client
    .get("https://www.rust-lang.org")
    .header(USER_AGENT, "My Rust Program 1.0")
    .send()
    .await?;

How do I add custom headers?

如果您查看 header 的签名，您会发现它接受通用类型：

pub fn header<K, V>(self, key: K, value: V) -> RequestBuilder where
    HeaderName: TryFrom<K>,
    <HeaderName as TryFrom<K>>::Error: Into<Error>,
    HeaderValue: TryFrom<V>,
    <HeaderValue as TryFrom<V>>::Error: Into<Error>,

有an implementation of TryFrom<&'a str> for HeaderName，所以可以使用字符串字面量：

use reqwest; // 0.10.0
use tokio; // 0.2.6

#[tokio::main]
async fn main() -> Result<(), reqwest::Error> {
    let client = reqwest::Client::new();
    let res = client
        .get("https://www.rust-lang.org")
        .header("X-My-Custom-Header", "foo")
        .send()
        .await?;

    Ok(())
}

Answer 2

在版本为 ~0.9.19 的 reqwest 客户端中发送 Cookie

use reqwest; // 0.9.19
use http::{HeaderMap, HeaderValue, header::{COOKIE}};

// create client first
let init_client = reqwest::Client::builder()
        .cookie_store(true).build().unwrap();
// create Header Map
// Here cookie store is optional based on if making more than one request with the // same client 
let mut headers = HeaderMap::new();
headers.insert(COOKIE, HeaderValue::from_str("key=value").unwrap());
let resp = init_client.get("api")
           .headers(headers)
           .query(&[("name", "foo")])
           .send()
           .map(|resp|{
               println!("{:?}", resp.status());
               resp
           })
           .map_err(|err|{
              println!("{:?}", err);
              err
           });

希望这可能有所帮助。

如何使用 Reqwest 设置请求 headers？

How do I set the request headers using Reqwest?

http

http-headers

rust

reqwest

要求 0.10