1#![doc(html_root_url = "https://docs.rs/http/0.2.11")]
2
3//! A general purpose library of common HTTP types
4//!
5//! This crate is a general purpose library for common types found when working
6//! with the HTTP protocol. You'll find `Request` and `Response` types for
7//! working as either a client or a server as well as all of their components.
8//! Notably you'll find `Uri` for what a `Request` is requesting, a `Method`
9//! for how it's being requested, a `StatusCode` for what sort of response came
10//! back, a `Version` for how this was communicated, and
11//! `HeaderName`/`HeaderValue` definitions to get grouped in a `HeaderMap` to
12//! work with request/response headers.
13//!
14//! You will notably *not* find an implementation of sending requests or
15//! spinning up a server in this crate. It's intended that this crate is the
16//! "standard library" for HTTP clients and servers without dictating any
17//! particular implementation. Note that this crate is still early on in its
18//! lifecycle so the support libraries that integrate with the `http` crate are
19//! a work in progress! Stay tuned and we'll be sure to highlight crates here
20//! in the future.
21//!
22//! ## Requests and Responses
23//!
24//! Perhaps the main two types in this crate are the `Request` and `Response`
25//! types. A `Request` could either be constructed to get sent off as a client
26//! or it can also be received to generate a `Response` for a server. Similarly
27//! as a client a `Response` is what you get after sending a `Request`, whereas
28//! on a server you'll be manufacturing a `Response` to send back to the client.
29//!
30//! Each type has a number of accessors for the component fields. For as a
31//! server you might want to inspect a requests URI to dispatch it:
32//!
33//! ```
34//! use http::{Request, Response};
35//!
36//! fn response(req: Request<()>) -> http::Result<Response<()>> {
37//! match req.uri().path() {
38//! "/" => index(req),
39//! "/foo" => foo(req),
40//! "/bar" => bar(req),
41//! _ => not_found(req),
42//! }
43//! }
44//! # fn index(_req: Request<()>) -> http::Result<Response<()>> { panic!() }
45//! # fn foo(_req: Request<()>) -> http::Result<Response<()>> { panic!() }
46//! # fn bar(_req: Request<()>) -> http::Result<Response<()>> { panic!() }
47//! # fn not_found(_req: Request<()>) -> http::Result<Response<()>> { panic!() }
48//! ```
49//!
50//! On a `Request` you'll also find accessors like `method` to return a
51//! `Method` and `headers` to inspect the various headers. A `Response`
52//! has similar methods for headers, the status code, etc.
53//!
54//! In addition to getters, request/response types also have mutable accessors
55//! to edit the request/response:
56//!
57//! ```
58//! use http::{HeaderValue, Response, StatusCode};
59//! use http::header::CONTENT_TYPE;
60//!
61//! fn add_server_headers<T>(response: &mut Response<T>) {
62//! response.headers_mut()
63//! .insert(CONTENT_TYPE, HeaderValue::from_static("text/html"));
64//! *response.status_mut() = StatusCode::OK;
65//! }
66//! ```
67//!
68//! And finally, one of the most important aspects of requests/responses, the
69//! body! The `Request` and `Response` types in this crate are *generic* in
70//! what their body is. This allows downstream libraries to use different
71//! representations such as `Request<Vec<u8>>`, `Response<impl Read>`,
72//! `Request<impl Stream<Item = Vec<u8>, Error = _>>`, or even
73//! `Response<MyCustomType>` where the custom type was deserialized from JSON.
74//!
75//! The body representation is intentionally flexible to give downstream
76//! libraries maximal flexibility in implementing the body as appropriate.
77//!
78//! ## HTTP Headers
79//!
80//! Another major piece of functionality in this library is HTTP header
81//! interpretation and generation. The `HeaderName` type serves as a way to
82//! define header *names*, or what's to the left of the colon. A `HeaderValue`
83//! conversely is the header *value*, or what's to the right of a colon.
84//!
85//! For example, if you have an HTTP request that looks like:
86//!
87//! ```http
88//! GET /foo HTTP/1.1
89//! Accept: text/html
90//! ```
91//!
92//! Then `"Accept"` is a `HeaderName` while `"text/html"` is a `HeaderValue`.
93//! Each of these is a dedicated type to allow for a number of interesting
94//! optimizations and to also encode the static guarantees of each type. For
95//! example a `HeaderName` is always a valid `&str`, but a `HeaderValue` may
96//! not be valid UTF-8.
97//!
98//! The most common header names are already defined for you as constant values
99//! in the `header` module of this crate. For example:
100//!
101//! ```
102//! use http::header::{self, HeaderName};
103//!
104//! let name: HeaderName = header::ACCEPT;
105//! assert_eq!(name.as_str(), "accept");
106//! ```
107//!
108//! You can, however, also parse header names from strings:
109//!
110//! ```
111//! use http::header::{self, HeaderName};
112//!
113//! let name = "Accept".parse::<HeaderName>().unwrap();
114//! assert_eq!(name, header::ACCEPT);
115//! ```
116//!
117//! Header values can be created from string literals through the `from_static`
118//! function:
119//!
120//! ```
121//! use http::HeaderValue;
122//!
123//! let value = HeaderValue::from_static("text/html");
124//! assert_eq!(value.as_bytes(), b"text/html");
125//! ```
126//!
127//! And header values can also be parsed like names:
128//!
129//! ```
130//! use http::HeaderValue;
131//!
132//! let value = "text/html";
133//! let value = value.parse::<HeaderValue>().unwrap();
134//! ```
135//!
136//! Most HTTP requests and responses tend to come with more than one header, so
137//! it's not too useful to just work with names and values only! This crate also
138//! provides a `HeaderMap` type which is a specialized hash map for keys as
139//! `HeaderName` and generic values. This type, like header names, is optimized
140//! for common usage but should continue to scale with your needs over time.
141//!
142//! # URIs
143//!
144//! Each HTTP `Request` has an associated URI with it. This may just be a path
145//! like `/index.html` but it could also be an absolute URL such as
146//! `https://www.rust-lang.org/index.html`. A `URI` has a number of accessors to
147//! interpret it:
148//!
149//! ```
150//! use http::Uri;
151//! use http::uri::Scheme;
152//!
153//! let uri = "https://www.rust-lang.org/index.html".parse::<Uri>().unwrap();
154//!
155//! assert_eq!(uri.scheme(), Some(&Scheme::HTTPS));
156//! assert_eq!(uri.host(), Some("www.rust-lang.org"));
157//! assert_eq!(uri.path(), "/index.html");
158//! assert_eq!(uri.query(), None);
159//! ```
160
161#![deny(missing_docs, missing_debug_implementations)]
162
163#[cfg(test)]
164#[macro_use]
165extern crate doc_comment;
166
167#[cfg(test)]
168doctest!("../README.md");
169
170#[macro_use]
171mod convert;
172
173pub mod header;
174pub mod method;
175pub mod request;
176pub mod response;
177pub mod status;
178pub mod uri;
179pub mod version;
180
181mod byte_str;
182mod error;
183mod extensions;
184
185pub use crate::error::{Error, Result};
186pub use crate::extensions::Extensions;
187#[doc(no_inline)]
188pub use crate::header::{HeaderMap, HeaderName, HeaderValue};
189pub use crate::method::Method;
190pub use crate::request::Request;
191pub use crate::response::Response;
192pub use crate::status::StatusCode;
193pub use crate::uri::Uri;
194pub use crate::version::Version;
195
196fn _assert_types() {
197 fn assert_send<T: Send>() {}
198 fn assert_sync<T: Sync>() {}
199
200 assert_send::<Request<()>>();
201 assert_send::<Response<()>>();
202
203 assert_sync::<Request<()>>();
204 assert_sync::<Response<()>>();
205}
206
207mod sealed {
208 /// Private trait to this crate to prevent traits from being implemented in
209 /// downstream crates.
210 pub trait Sealed {}
211}
212