headers/common/
access_control_allow_headers.rs

1use std::iter::FromIterator;
2
3use util::FlatCsv;
4use {HeaderName, HeaderValue};
5
6/// `Access-Control-Allow-Headers` header, part of
7/// [CORS](http://www.w3.org/TR/cors/#access-control-allow-headers-response-header)
8///
9/// The `Access-Control-Allow-Headers` header indicates, as part of the
10/// response to a preflight request, which header field names can be used
11/// during the actual request.
12///
13/// # ABNF
14///
15/// ```text
16/// Access-Control-Allow-Headers: "Access-Control-Allow-Headers" ":" #field-name
17/// ```
18///
19/// # Example values
20/// * `accept-language, date`
21///
22/// # Examples
23///
24/// ```
25/// # extern crate headers;
26/// extern crate http;
27/// use http::header::{CACHE_CONTROL, CONTENT_TYPE};
28/// use headers::AccessControlAllowHeaders;
29///
30/// let allow_headers = vec![CACHE_CONTROL, CONTENT_TYPE]
31///     .into_iter()
32///     .collect::<AccessControlAllowHeaders>();
33/// ```
34#[derive(Clone, Debug, PartialEq)]
35pub struct AccessControlAllowHeaders(FlatCsv);
36
37derive_header! {
38    AccessControlAllowHeaders(_),
39    name: ACCESS_CONTROL_ALLOW_HEADERS
40}
41
42impl AccessControlAllowHeaders {
43    /// Returns an iterator over `HeaderName`s contained within.
44    pub fn iter<'a>(&'a self) -> impl Iterator<Item = HeaderName> + 'a {
45        self.0
46            .iter()
47            .map(|s| s.parse().ok())
48            .take_while(|val| val.is_some())
49            .filter_map(|val| val)
50    }
51}
52
53impl FromIterator<HeaderName> for AccessControlAllowHeaders {
54    fn from_iter<I>(iter: I) -> Self
55    where
56        I: IntoIterator<Item = HeaderName>,
57    {
58        let flat = iter.into_iter().map(HeaderValue::from).collect();
59        AccessControlAllowHeaders(flat)
60    }
61}
62
63#[cfg(test)]
64mod tests {
65    use super::super::{test_decode, test_encode};
66    use super::*;
67
68    #[test]
69    fn iter() {
70        let allow_headers = test_decode::<AccessControlAllowHeaders>(&["foo, bar"]).unwrap();
71
72        let as_vec = allow_headers.iter().collect::<Vec<_>>();
73        assert_eq!(as_vec.len(), 2);
74        assert_eq!(as_vec[0], "foo");
75        assert_eq!(as_vec[1], "bar");
76    }
77
78    #[test]
79    fn from_iter() {
80        let allow: AccessControlAllowHeaders =
81            vec![::http::header::CACHE_CONTROL, ::http::header::IF_RANGE]
82                .into_iter()
83                .collect();
84
85        let headers = test_encode(allow);
86        assert_eq!(
87            headers["access-control-allow-headers"],
88            "cache-control, if-range"
89        );
90    }
91
92    #[test]
93    fn test_with_invalid() {
94        let allow_headers = test_decode::<AccessControlAllowHeaders>(&["foo foo, bar"]).unwrap();
95
96        assert!(allow_headers.iter().collect::<Vec<_>>().is_empty());
97    }
98}