#![deny(missing_docs)]
#![deny(missing_debug_implementations)]
#![cfg_attr(test, deny(warnings))]
#![doc(html_root_url = "
https://docs.rs/headers-core/0.2.0")]
//! # headers-core
//!
//! This is the core crate of the typed HTTP headers system, providing only
//! the relevant traits. All actual header implementations are in other crates.
extern crate http;
pub use http::header::{self, HeaderName, HeaderValue};
use std::error;
use std::fmt::{self, Display, Formatter};
/// A trait for any object that will represent a header field and value.
///
/// This trait represents the construction and identification of headers,
/// and contains trait-object unsafe methods.
pub trait Header {
/// The name of this header.
fn name() -> &'static HeaderName;
/// Decode this type from an iterator of `HeaderValue`s.
fn decode<'i, I>(values: &mut I) -> Result<Self, Error>
where
Self: Sized,
I: Iterator<Item = &'i HeaderValue>;
/// Encode this type to a `HeaderMap`.
///
/// This function should be infallible. Any errors converting to a
/// `HeaderValue` should have been caught when parsing or constructing
/// this value.
fn encode<E: Extend<HeaderValue>>(&self, values: &mut E);
}
/// Errors trying to decode a header.
#[derive(Debug)]
pub struct Error {
kind: Kind,
}
#[derive(Debug)]
enum Kind {
Invalid,
}
impl Error {
/// Create an 'invalid' Error.
pub fn invalid() -> Error {
Error {
kind: Kind::Invalid,
}
}
}
impl Display for Error {
fn fmt(&self, f: &mut Formatter) -> fmt::Result {
match &self.kind {
Kind::Invalid => f.write_str("invalid HTTP header"),
}
}
}
impl error::Error for Error {}
