headers/common/
connection.rs

1use std::iter::FromIterator;
2
3use http::{HeaderName, HeaderValue};
4
5use self::sealed::AsConnectionOption;
6use crate::util::FlatCsv;
7
8/// `Connection` header, defined in
9/// [RFC7230](https://datatracker.ietf.org/doc/html/rfc7230#section-6.1)
10///
11/// The `Connection` header field allows the sender to indicate desired
12/// control options for the current connection.  In order to avoid
13/// confusing downstream recipients, a proxy or gateway MUST remove or
14/// replace any received connection options before forwarding the
15/// message.
16///
17/// # ABNF
18///
19/// ```text
20/// Connection        = 1#connection-option
21/// connection-option = token
22///
23/// # Example values
24/// * `close`
25/// * `keep-alive`
26/// * `upgrade`
27/// ```
28///
29/// # Examples
30///
31/// ```
32/// use headers::Connection;
33///
34/// let keep_alive = Connection::keep_alive();
35/// ```
36// This is frequently just 1 or 2 values, so optimize for that case.
37#[derive(Clone, Debug)]
38pub struct Connection(FlatCsv);
39
40derive_header! {
41    Connection(_),
42    name: CONNECTION
43}
44
45impl Connection {
46    /// A constructor to easily create a `Connection: close` header.
47    #[inline]
48    pub fn close() -> Connection {
49        Connection(HeaderValue::from_static("close").into())
50    }
51
52    /// A constructor to easily create a `Connection: keep-alive` header.
53    #[inline]
54    pub fn keep_alive() -> Connection {
55        Connection(HeaderValue::from_static("keep-alive").into())
56    }
57
58    /// A constructor to easily create a `Connection: Upgrade` header.
59    #[inline]
60    pub fn upgrade() -> Connection {
61        Connection(HeaderValue::from_static("upgrade").into())
62    }
63
64    /// Check if this header contains a given "connection option".
65    ///
66    /// This can be used with various argument types:
67    ///
68    /// - `&str`
69    /// - `&HeaderName`
70    /// - `HeaderName`
71    ///
72    /// # Example
73    ///
74    /// ```
75    /// extern crate http;
76    ///
77    /// use http::header::UPGRADE;
78    /// use headers::Connection;
79    ///
80    /// let conn = Connection::keep_alive();
81    ///
82    /// assert!(!conn.contains("close"));
83    /// assert!(!conn.contains(UPGRADE));
84    /// assert!(conn.contains("keep-alive"));
85    /// assert!(conn.contains("Keep-Alive"));
86    /// ```
87    pub fn contains(&self, name: impl AsConnectionOption) -> bool {
88        let s = name.as_connection_option();
89        self.0.iter().any(|opt| opt.eq_ignore_ascii_case(s))
90    }
91}
92
93impl FromIterator<HeaderName> for Connection {
94    fn from_iter<I>(iter: I) -> Self
95    where
96        I: IntoIterator<Item = HeaderName>,
97    {
98        let flat = iter.into_iter().map(HeaderValue::from).collect();
99        Connection(flat)
100    }
101}
102
103mod sealed {
104    use http::HeaderName;
105
106    pub trait AsConnectionOption: Sealed {
107        fn as_connection_option(&self) -> &str;
108    }
109    pub trait Sealed {}
110
111    impl AsConnectionOption for &str {
112        fn as_connection_option(&self) -> &str {
113            self
114        }
115    }
116
117    impl Sealed for &str {}
118
119    impl AsConnectionOption for &HeaderName {
120        fn as_connection_option(&self) -> &str {
121            self.as_ref()
122        }
123    }
124
125    impl Sealed for &HeaderName {}
126
127    impl AsConnectionOption for HeaderName {
128        fn as_connection_option(&self) -> &str {
129            self.as_ref()
130        }
131    }
132
133    impl Sealed for HeaderName {}
134}
headers/common/connection.rs

headers/common/
connection.rs
