hyper_sync/header/common/
preference_applied.rs

1use std::fmt;
2
3use header::{Header, Raw, Preference};
4use header::parsing::{from_comma_delimited, fmt_comma_delimited};
5
6/// `Preference-Applied` header, defined in [RFC7240](http://tools.ietf.org/html/rfc7240)
7///
8/// The `Preference-Applied` response header may be included within a
9/// response message as an indication as to which `Prefer` header tokens were
10/// honored by the server and applied to the processing of a request.
11///
12/// # ABNF
13///
14/// ```text
15/// Preference-Applied = "Preference-Applied" ":" 1#applied-pref
16/// applied-pref = token [ BWS "=" BWS word ]
17/// ```
18///
19/// # Example values
20///
21/// * `respond-async`
22/// * `return=minimal`
23/// * `wait=30`
24///
25/// # Examples
26///
27/// ```
28/// use hyper_sync::header::{Headers, PreferenceApplied, Preference};
29///
30/// let mut headers = Headers::new();
31/// headers.set(
32///     PreferenceApplied(vec![Preference::RespondAsync])
33/// );
34/// ```
35///
36/// ```
37/// use hyper_sync::header::{Headers, PreferenceApplied, Preference};
38///
39/// let mut headers = Headers::new();
40/// headers.set(
41///     PreferenceApplied(vec![
42///         Preference::RespondAsync,
43///         Preference::ReturnRepresentation,
44///         Preference::Wait(10u32),
45///         Preference::Extension("foo".to_owned(),
46///                               "bar".to_owned(),
47///                               vec![]),
48///     ])
49/// );
50/// ```
51#[derive(PartialEq, Clone, Debug)]
52pub struct PreferenceApplied(pub Vec<Preference>);
53
54__hyper__deref!(PreferenceApplied => Vec<Preference>);
55
56impl Header for PreferenceApplied {
57    fn header_name() -> &'static str {
58        static NAME: &'static str = "Preference-Applied";
59        NAME
60    }
61
62    fn parse_header(raw: &Raw) -> ::Result<PreferenceApplied> {
63        let preferences = try!(from_comma_delimited(raw));
64        if !preferences.is_empty() {
65            Ok(PreferenceApplied(preferences))
66        } else {
67            Err(::Error::Header)
68        }
69    }
70
71    fn fmt_header(&self, f: &mut ::header::Formatter) -> fmt::Result {
72        f.fmt_line(self)
73    }
74}
75
76impl fmt::Display for PreferenceApplied {
77    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
78        //TODO: format this without allocating a Vec and cloning contents
79        let preferences: Vec<_> = self.0.iter().map(|pref| match pref {
80            // The spec ignores parameters in `Preferences-Applied`
81            &Preference::Extension(ref name, ref value, _) => Preference::Extension(
82              name.to_owned(),
83              value.to_owned(),
84              vec![]
85            ),
86            preference => preference.clone()
87        }).collect();
88        fmt_comma_delimited(f, &preferences)
89    }
90}
91
92#[cfg(test)]
93mod tests {
94    use header::Preference;
95    use super::*;
96
97    #[test]
98    fn test_format_ignore_parameters() {
99        assert_eq!(
100            format!("{}", PreferenceApplied(vec![Preference::Extension(
101                "foo".to_owned(),
102                "bar".to_owned(),
103                vec![("bar".to_owned(), "foo".to_owned()), ("buz".to_owned(), "".to_owned())]
104            )])),
105            "foo=bar".to_owned()
106        );
107    }
108}
109
110bench_header!(normal,
111    PreferenceApplied, { vec![b"respond-async, return=representation".to_vec(), b"wait=100".to_vec()] });
hyper_sync/header/common/preference_applied.rs

hyper_sync/header/common/
preference_applied.rs
