tower_http/follow_redirect/policy/
limited.rs

1use super::{Action, Attempt, Policy};
2
3/// A redirection [`Policy`] that limits the number of successive redirections.
4#[derive(Clone, Copy, Debug)]
5pub struct Limited {
6    remaining: usize,
7}
8
9impl Limited {
10    /// Create a new [`Limited`] with a limit of `max` redirections.
11    pub fn new(max: usize) -> Self {
12        Limited { remaining: max }
13    }
14}
15
16impl Default for Limited {
17    /// Returns the default [`Limited`] with a limit of `20` redirections.
18    fn default() -> Self {
19        // This is the (default) limit of Firefox and the Fetch API.
20        // https://hg.mozilla.org/mozilla-central/file/6264f13d54a1caa4f5b60303617a819efd91b8ee/modules/libpref/init/all.js#l1371
21        // https://fetch.spec.whatwg.org/#http-redirect-fetch
22        Limited::new(20)
23    }
24}
25
26impl<B, E> Policy<B, E> for Limited {
27    fn redirect(&mut self, _: &Attempt<'_>) -> Result<Action, E> {
28        if self.remaining > 0 {
29            self.remaining -= 1;
30            Ok(Action::Follow)
31        } else {
32            Ok(Action::Stop)
33        }
34    }
35}
36
37#[cfg(test)]
38mod tests {
39    use http::{Request, Uri};
40
41    use super::*;
42
43    #[test]
44    fn works() {
45        let uri = Uri::from_static("https://example.com/");
46        let mut policy = Limited::new(2);
47
48        for _ in 0..2 {
49            let mut request = Request::builder().uri(uri.clone()).body(()).unwrap();
50            Policy::<(), ()>::on_request(&mut policy, &mut request);
51
52            let attempt = Attempt {
53                status: Default::default(),
54                location: &uri,
55                previous: &uri,
56            };
57            assert!(Policy::<(), ()>::redirect(&mut policy, &attempt)
58                .unwrap()
59                .is_follow());
60        }
61
62        let mut request = Request::builder().uri(uri.clone()).body(()).unwrap();
63        Policy::<(), ()>::on_request(&mut policy, &mut request);
64
65        let attempt = Attempt {
66            status: Default::default(),
67            location: &uri,
68            previous: &uri,
69        };
70        assert!(Policy::<(), ()>::redirect(&mut policy, &attempt)
71            .unwrap()
72            .is_stop());
73    }
74}
tower_http/follow_redirect/policy/limited.rs

tower_http/follow_redirect/policy/
limited.rs
