headers/common/
content_length.rs

Help
1use {Header, HeaderValue};
2
3/// `Content-Length` header, defined in
4/// [RFC7230](http://tools.ietf.org/html/rfc7230#section-3.3.2)
5///
6/// When a message does not have a `Transfer-Encoding` header field, a
7/// Content-Length header field can provide the anticipated size, as a
8/// decimal number of octets, for a potential payload body.  For messages
9/// that do include a payload body, the Content-Length field-value
10/// provides the framing information necessary for determining where the
11/// body (and message) ends.  For messages that do not include a payload
12/// body, the Content-Length indicates the size of the selected
13/// representation.
14///
15/// Note that setting this header will *remove* any previously set
16/// `Transfer-Encoding` header, in accordance with
17/// [RFC7230](http://tools.ietf.org/html/rfc7230#section-3.3.2):
18///
19/// > A sender MUST NOT send a Content-Length header field in any message
20/// > that contains a Transfer-Encoding header field.
21///
22/// ## ABNF
23///
24/// ```text
25/// Content-Length = 1*DIGIT
26/// ```
27///
28/// ## Example values
29///
30/// * `3495`
31///
32/// # Example
33///
34/// ```
35/// # extern crate headers;
36/// use headers::ContentLength;
37///
38/// let len = ContentLength(1_000);
39/// ```
40#[derive(Clone, Copy, Debug, PartialEq)]
41pub struct ContentLength(pub u64);
42
43impl Header for ContentLength {
44    fn name() -> &'static ::http::header::HeaderName {
45        &::http::header::CONTENT_LENGTH
46    }
47
48    fn decode<'i, I: Iterator<Item = &'i HeaderValue>>(values: &mut I) -> Result<Self, ::Error> {
49        // If multiple Content-Length headers were sent, everything can still
50        // be alright if they all contain the same value, and all parse
51        // correctly. If not, then it's an error.
52        let mut len = None;
53        for value in values {
54            let parsed = value
55                .to_str()
56                .map_err(|_| ::Error::invalid())?
57                .parse::<u64>()
58                .map_err(|_| ::Error::invalid())?;
59
60            if let Some(prev) = len {
61                if prev != parsed {
62                    return Err(::Error::invalid());
63                }
64            } else {
65                len = Some(parsed);
66            }
67        }
68
69        len.map(ContentLength).ok_or_else(::Error::invalid)
70    }
71
72    fn encode<E: Extend<::HeaderValue>>(&self, values: &mut E) {
73        values.extend(::std::iter::once(self.0.into()));
74    }
75}
76
77/*
78__hyper__tm!(ContentLength, tests {
79    // Testcase from RFC
80    test_header!(test1, vec![b"3495"], Some(HeaderField(3495)));
81
82    test_header!(test_invalid, vec![b"34v95"], None);
83
84    // Can't use the test_header macro because "5, 5" gets cleaned to "5".
85    #[test]
86    fn test_duplicates() {
87        let parsed = HeaderField::parse_header(&vec![b"5".to_vec(),
88                                                 b"5".to_vec()].into()).unwrap();
89        assert_eq!(parsed, HeaderField(5));
90        assert_eq!(format!("{}", parsed), "5");
91    }
92
93    test_header!(test_duplicates_vary, vec![b"5", b"6", b"5"], None);
94});
95*/
headers/common/content_length.rs

headers/common/
content_length.rs
