use self::sealed::AsCoding;
use util::FlatCsv;
use HeaderValue;
/// `Content-Encoding` header, defined in
/// [RFC7231](
http://tools.ietf.org/html/rfc7231#section-3.1.2.2)
///
/// The `Content-Encoding` header field indicates what content codings
/// have been applied to the representation, beyond those inherent in the
/// media type, and thus what decoding mechanisms have to be applied in
/// order to obtain data in the media type referenced by the Content-Type
/// header field. Content-Encoding is primarily used to allow a
/// representation's data to be compressed without losing the identity of
/// its underlying media type.
///
/// # ABNF
///
/// ```text
/// Content-Encoding = 1#content-coding
/// ```
///
/// # Example values
///
/// * `gzip`
///
/// # Examples
///
/// ```
/// # extern crate headers;
/// use headers::ContentEncoding;
///
/// let content_enc = ContentEncoding::gzip();
/// ```
#[derive(Clone, Debug)]
pub struct ContentEncoding(FlatCsv);
derive_header! {
ContentEncoding(_),
name: CONTENT_ENCODING
}
impl ContentEncoding {
/// A constructor to easily create a `Content-Encoding: gzip` header.
#[inline]
pub fn gzip() -> ContentEncoding {
ContentEncoding(HeaderValue::from_static("gzip").into())
}
/// Check if this header contains a given "coding".
///
/// This can be used with these argument types:
///
/// - `&str`
///
/// # Example
///
/// ```
/// # extern crate headers;
/// use headers::ContentEncoding;
///
/// let content_enc = ContentEncoding::gzip();
///
/// assert!(content_enc.contains("gzip"));
/// assert!(!content_enc.contains("br"));
/// ```
pub fn contains(&self, coding: impl AsCoding) -> bool {
let s = coding.as_coding();
self.0.iter().find(|&opt| opt == s).is_some()
}
}
mod sealed {
pub trait AsCoding: Sealed {}
pub trait Sealed {
fn as_coding(&self) -> &str;
}
impl<'a> AsCoding for &'a str {}
impl<'a> Sealed for &'a str {
fn as_coding(&self) -> &str {
*self
}
}
}
