rama_http/layer/trace/
on_request.rs

1use super::DEFAULT_MESSAGE_LEVEL;
2use crate::Request;
3use rama_core::telemetry::tracing::{Level, Span};
4
5/// Trait used to tell [`Trace`] what to do when a request is received.
6///
7/// See the [module docs](../trace/index.html#on_request) for details on exactly when the
8/// `on_request` callback is called.
9///
10/// [`Trace`]: super::Trace
11pub trait OnRequest<B>: Send + Sync + 'static {
12    /// Do the thing.
13    ///
14    /// `span` is the `tracing` [`Span`], corresponding to this request, produced by the closure
15    /// passed to [`TraceLayer::make_span_with`]. It can be used to [record field values][record]
16    /// that weren't known when the span was created.
17    ///
18    /// [`Span`]: https://docs.rs/tracing/latest/tracing/span/index.html
19    /// [record]: https://docs.rs/tracing/latest/tracing/span/struct.Span.html#method.record
20    /// [`TraceLayer::make_span_with`]: crate::layer::trace::TraceLayer::make_span_with
21    fn on_request(&self, request: &Request<B>, span: &Span);
22}
23
24impl<B> OnRequest<B> for () {
25    #[inline]
26    fn on_request(&self, _: &Request<B>, _: &Span) {}
27}
28
29impl<B, F> OnRequest<B> for F
30where
31    F: Fn(&Request<B>, &Span) + Send + Sync + 'static,
32{
33    fn on_request(&self, request: &Request<B>, span: &Span) {
34        self(request, span)
35    }
36}
37
38/// The default [`OnRequest`] implementation used by [`Trace`].
39///
40/// [`Trace`]: super::Trace
41#[derive(Clone, Debug)]
42pub struct DefaultOnRequest {
43    level: Level,
44}
45
46impl Default for DefaultOnRequest {
47    fn default() -> Self {
48        Self {
49            level: DEFAULT_MESSAGE_LEVEL,
50        }
51    }
52}
53
54impl DefaultOnRequest {
55    /// Create a new `DefaultOnRequest`.
56    #[must_use]
57    pub fn new() -> Self {
58        Self::default()
59    }
60
61    rama_utils::macros::generate_set_and_with! {
62        /// Set the [`Level`] used for [tracing events].
63        ///
64        /// Please note that while this will set the level for the tracing events
65        /// themselves, it might cause them to lack expected information, like
66        /// request method or path. You can address this using
67        /// [`DefaultMakeSpan::level`].
68        ///
69        /// Defaults to [`Level::DEBUG`].
70        ///
71        /// [tracing events]: https://docs.rs/tracing/latest/tracing/#events
72        /// [`DefaultMakeSpan::level`]: crate::layer::trace::DefaultMakeSpan::level
73        pub fn level(mut self, level: Level) -> Self {
74            self.level = level;
75            self
76        }
77    }
78}
79
80impl<B> OnRequest<B> for DefaultOnRequest {
81    fn on_request(&self, _: &Request<B>, span: &Span) {
82        event_dynamic_lvl!(
83            parent: span,
84            self.level,
85            "started processing request",
86        );
87    }
88}
rama_http/layer/trace/on_request.rs

rama_http/layer/trace/
on_request.rs
