parse_link_header

A library for parsing HTTP Link header.

• How to use
  • Note for version 0.1.x
  • Example
• parse_with_rel
• Feature: url
• How to contribute
• License

How to use

Note for version 0.1.x

The version 0.1 can't correctly handle the relative ref which described in https://tools.ietf.org/html/rfc3986#section-4.1

The parsed value of version 0.1 refers to the return value of https://github.com/thlorenz/parse-link-header, which is a HashMap with the same structure.

So if you want to parse relative ref, please use version >=0.2.

Or if you don't care about relative ref and want a simple HashMap<String, HashMap<String, String>> result, you can use version 0.1.

Example

In your Cargo.toml, add:

[dependencies]
parse_link_header = "0.4"

Then:

let link_header = r#"<https://api.github.com/repositories/41986369/contributors?page=2>; rel="next", <https://api.github.com/repositories/41986369/contributors?page=14>; rel="last""#;

let res = parse_link_header::parse(link_header);
assert!(res.is_ok());

let val = res.unwrap();
assert_eq!(val.len(), 2);
assert_eq!(val.get(&Some("next".to_string())).unwrap().raw_uri, "https://api.github.com/repositories/41986369/contributors?page=2");
assert_eq!(val.get(&Some("last".to_string())).unwrap().raw_uri, "https://api.github.com/repositories/41986369/contributors?page=14");

The parsed value is a Result<HashMap<Option<Rel>, Link>, Error> (aka a LinkMap), which Rel and Link is:

use std::collections::HashMap;

#[cfg(not(feature = "url"))]
use http::Uri;

#[cfg(feature = "url")]
use url::Url as Uri;

#[derive(Debug, PartialEq)]
pub struct Link {
    pub uri: Uri,
    pub raw_uri: String,
    pub queries: HashMap<String, String>,
    pub params: HashMap<String, String>,
}

type Rel = String;

Note that according to https://tools.ietf.org/html/rfc8288#section-3.3 (October 2017), the rel parameter must be present. That's why the key of HashMap<Option<Rel>, Link> is Option<Rel>. So if you find that the key is None, check if you specified the rel type.

parse_with_rel

Version >= 0.3.0

Alternatively, use the parse_with_rel() function to get a HashMap<String, Link> (aka a RelLinkMap), as in:

let link_header = r#"<https://api.github.com/repositories/41986369/contributors?page=2>; rel="next", <https://api.github.com/repositories/41986369/contributors?page=14>; rel="last""#;

let res = parse_link_header::parse_with_rel(link_header);
assert!(res.is_ok());

let val = res.unwrap();
assert_eq!(val.len(), 2);
assert_eq!(val.get("next").unwrap().raw_uri, "https://api.github.com/repositories/41986369/contributors?page=2");
assert_eq!(val.get("last").unwrap().raw_uri, "https://api.github.com/repositories/41986369/contributors?page=14");

You can use this function if you ensure that the rel parameter is present in the header.

Feature: url

Version >= 0.3.0

If the url feature is enabled, the uri field in struct parse_link_header::Link will be of type url::Url from the url crate, rather than the http::uri::Uri it normally is. This allows integration with other libraries that use the url crate, such as reqwest.

NOTE: This implicitly disabled support for relative refs, as URLs do not support relative refs (whereas URIs do).

How to contribute

Pull a request or open an issue to describe your changes or problems.

License

MIT @ g1eny0ung