sentry-tracing 0.48.0

Sentry integration for the tracing and tracing-subscriber crates.
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79

//! This module contains code for stack-like storage for `HubSwitchGuard`s keyed
//! by tracing span ID.

use std::collections::hash_map::Entry;
use std::collections::HashMap;

use sentry_core::HubSwitchGuard;
use tracing_core::span::Id as SpanId;

/// Holds per-span stacks of `HubSwitchGuard`s to handle span re-entrancy.
///
/// Each time a span is entered, we should push a new guard onto the stack.
/// When the span exits, we should pop the guard from the stack.
pub(super) struct SpanGuardStack {
    /// The map of span IDs to their respective guard stacks.
    guards: HashMap<SpanId, Vec<HubSwitchGuard>>,
}

impl SpanGuardStack {
    /// Creates an empty guard stack map.
    pub(super) fn new() -> Self {
        Self {
            guards: HashMap::new(),
        }
    }

    /// Pushes a guard for the given span ID, creating the stack if needed.
    pub(super) fn push(&mut self, id: SpanId, guard: HubSwitchGuard) {
        self.guards.entry(id).or_default().push(guard);
    }

    /// Pops the most recent guard for the span ID, removing the stack when empty.
    #[must_use]
    pub(super) fn pop(&mut self, id: SpanId) -> Option<HubSwitchGuard> {
        match self.guards.entry(id) {
            Entry::Occupied(mut entry) => {
                let stack = entry.get_mut();
                let guard = stack.pop();
                if stack.is_empty() {
                    entry.remove();
                }
                guard
            }
            Entry::Vacant(_) => None,
        }
    }
}

#[cfg(test)]
mod tests {
    use super::SpanGuardStack;
    use sentry_core::{Hub, HubSwitchGuard};
    use std::sync::Arc;
    use tracing_core::span::Id as SpanId;

    #[test]
    fn pop_is_lifo() {
        let initial = Hub::current();
        let hub_a = Arc::new(Hub::new_from_top(initial.clone()));
        let hub_b = Arc::new(Hub::new_from_top(hub_a.clone()));

        let mut stack = SpanGuardStack::new();
        let id = SpanId::from_u64(1);

        stack.push(id.clone(), HubSwitchGuard::new(hub_a.clone()));
        assert!(Arc::ptr_eq(&Hub::current(), &hub_a));

        stack.push(id.clone(), HubSwitchGuard::new(hub_b.clone()));
        assert!(Arc::ptr_eq(&Hub::current(), &hub_b));

        drop(stack.pop(id.clone()).expect("guard for hub_b"));
        assert!(Arc::ptr_eq(&Hub::current(), &hub_a));

        drop(stack.pop(id.clone()).expect("guard for hub_a"));
        assert!(Arc::ptr_eq(&Hub::current(), &initial));

        assert!(stack.pop(id).is_none());
    }
}