http_types/cache/
age.rs

1use crate::headers::{HeaderName, HeaderValue, Headers, ToHeaderValues, AGE};
2use crate::Status;
3
4use std::fmt::Debug;
5use std::option;
6use std::time::Duration;
7
8/// HTTP `Age` header
9///
10/// # Specifications
11///
12/// - [RFC 7234, section 5.1: Age](https://tools.ietf.org/html/rfc7234#section-5.1)
13///
14/// # Examples
15///
16/// ```
17/// # fn main() -> http_types::Result<()> {
18/// #
19/// use http_types::Response;
20/// use http_types::cache::Age;
21///
22/// let age = Age::from_secs(12);
23///
24/// let mut res = Response::new(200);
25/// age.apply(&mut res);
26///
27/// let age = Age::from_headers(res)?.unwrap();
28/// assert_eq!(age, Age::from_secs(12));
29/// #
30/// # Ok(()) }
31/// ```
32#[derive(Debug, Ord, PartialOrd, Eq, PartialEq)]
33pub struct Age {
34    dur: Duration,
35}
36
37impl Age {
38    /// Create a new instance of `Age`.
39    pub fn new(dur: Duration) -> Self {
40        Self { dur }
41    }
42
43    /// Create a new instance of `Age` from secs.
44    pub fn from_secs(secs: u64) -> Self {
45        let dur = Duration::from_secs(secs);
46        Self { dur }
47    }
48
49    /// Get the duration from the header.
50    pub fn duration(&self) -> Duration {
51        self.dur
52    }
53
54    /// Create an instance of `Age` from a `Headers` instance.
55    pub fn from_headers(headers: impl AsRef<Headers>) -> crate::Result<Option<Self>> {
56        let headers = match headers.as_ref().get(AGE) {
57            Some(headers) => headers,
58            None => return Ok(None),
59        };
60
61        // If we successfully parsed the header then there's always at least one
62        // entry. We want the last entry.
63        let header = headers.iter().last().unwrap();
64
65        let num: u64 = header.as_str().parse().status(400)?;
66        let dur = Duration::from_secs_f64(num as f64);
67
68        Ok(Some(Self { dur }))
69    }
70
71    /// Insert a `HeaderName` + `HeaderValue` pair into a `Headers` instance.
72    pub fn apply(&self, mut headers: impl AsMut<Headers>) {
73        headers.as_mut().insert(AGE, self.value());
74    }
75
76    /// Get the `HeaderName`.
77    pub fn name(&self) -> HeaderName {
78        AGE
79    }
80
81    /// Get the `HeaderValue`.
82    pub fn value(&self) -> HeaderValue {
83        let output = self.dur.as_secs().to_string();
84
85        // SAFETY: the internal string is validated to be ASCII.
86        unsafe { HeaderValue::from_bytes_unchecked(output.into()) }
87    }
88}
89
90impl ToHeaderValues for Age {
91    type Iter = option::IntoIter<HeaderValue>;
92    fn to_header_values(&self) -> crate::Result<Self::Iter> {
93        // A HeaderValue will always convert into itself.
94        Ok(self.value().to_header_values().unwrap())
95    }
96}
97
98#[cfg(test)]
99mod test {
100    use super::*;
101    use crate::headers::Headers;
102
103    #[test]
104    fn smoke() -> crate::Result<()> {
105        let age = Age::new(Duration::from_secs(12));
106
107        let mut headers = Headers::new();
108        age.apply(&mut headers);
109
110        let age = Age::from_headers(headers)?.unwrap();
111        assert_eq!(age, Age::new(Duration::from_secs(12)));
112        Ok(())
113    }
114
115    #[test]
116    fn bad_request_on_parse_error() {
117        let mut headers = Headers::new();
118        headers.insert(AGE, "<nori ate the tag. yum.>");
119        let err = Age::from_headers(headers).unwrap_err();
120        assert_eq!(err.status(), 400);
121    }
122}
http_types/cache/age.rs

http_types/cache/
age.rs
