cogo_http/header/common/
expect.rs

1use std::fmt;
2use std::str;
3
4use unicase::UniCase;
5
6use crate::header::{Header, HeaderFormat};
7
8/// The `Expect` header.
9///
10/// > The "Expect" header field in a request indicates a certain set of
11/// > behaviors (expectations) that need to be supported by the server in
12/// > order to properly handle this request.  The only such expectation
13/// > defined by this specification is 100-continue.
14/// >
15/// >    Expect  = "100-continue"
16///
17/// # Example
18/// ```
19/// use cogo_http::header::{Headers, Expect};
20/// let mut headers = Headers::new();
21/// headers.set(Expect::Continue);
22/// ```
23#[derive(Copy, Clone, PartialEq, Debug)]
24pub enum Expect {
25    /// The value `100-continue`.
26    Continue
27}
28
29const EXPECT_CONTINUE: UniCase<&'static str> = UniCase("100-continue");
30
31impl Header for Expect {
32    fn header_name() -> &'static str {
33        "Expect"
34    }
35
36    fn parse_header(raw: &[Vec<u8>]) -> crate::Result<Expect> {
37        if raw.len() == 1 {
38            let text = unsafe {
39                // safe because:
40                // 1. we just checked raw.len == 1
41                // 2. we don't actually care if it's utf8, we just want to
42                //    compare the bytes with the "case" normalized. If it's not
43                //    utf8, then the byte comparison will fail, and we'll return
44                //    None. No big deal.
45                str::from_utf8_unchecked(raw.get_unchecked(0))
46            };
47            if UniCase(text) == EXPECT_CONTINUE {
48                Ok(Expect::Continue)
49            } else {
50                Err(crate::Error::Header)
51            }
52        } else {
53            Err(crate::Error::Header)
54        }
55    }
56}
57
58impl HeaderFormat for Expect {
59    fn fmt_header(&self, f: &mut fmt::Formatter) -> fmt::Result {
60        fmt::Display::fmt(self, f)
61    }
62}
63
64impl fmt::Display for Expect {
65    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
66        f.write_str("100-continue")
67    }
68}
cogo_http/header/common/expect.rs

cogo_http/header/common/
expect.rs
