relay_server/services/projects/cache/
handle.rs

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
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
use std::fmt;
use std::sync::Arc;

use relay_base_schema::project::ProjectKey;
use relay_config::Config;
use relay_system::Addr;
use tokio::sync::broadcast;

use super::state::Shared;
use crate::services::projects::cache::service::ProjectChange;
use crate::services::projects::cache::{Project, ProjectCache};

/// A synchronous handle to the [`ProjectCache`].
///
/// The handle allows lock free access to cached projects. It also acts as an interface
/// to the [`ProjectCacheService`](super::ProjectCacheService).
#[derive(Clone)]
pub struct ProjectCacheHandle {
    pub(super) shared: Arc<Shared>,
    pub(super) config: Arc<Config>,
    pub(super) service: Addr<ProjectCache>,
    pub(super) project_changes: broadcast::Sender<ProjectChange>,
}

impl ProjectCacheHandle {
    /// Returns the current project state for the `project_key`.
    pub fn get(&self, project_key: ProjectKey) -> Project<'_> {
        let project = self.shared.get_or_create(project_key);
        // Always trigger a fetch after retrieving the project to make sure the state is up to date.
        self.fetch(project_key);

        Project::new(project, &self.config)
    }

    /// Triggers a fetch/update check in the project cache for the supplied project.
    pub fn fetch(&self, project_key: ProjectKey) {
        self.service.send(ProjectCache::Fetch(project_key));
    }

    /// Returns a subscription to all [`ProjectChange`]'s.
    ///
    /// This stream notifies the subscriber about project state changes in the project cache.
    /// Events may arrive in arbitrary order and be delivered multiple times.
    pub fn changes(&self) -> broadcast::Receiver<ProjectChange> {
        self.project_changes.subscribe()
    }
}

impl fmt::Debug for ProjectCacheHandle {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        f.debug_struct("ProjectCacheHandle")
            .field("shared", &self.shared)
            .finish()
    }
}

#[cfg(test)]
mod test {
    use super::*;
    use crate::services::projects::project::ProjectState;

    impl ProjectCacheHandle {
        /// Creates a new [`ProjectCacheHandle`] for testing only.
        ///
        /// A project cache handle created this way does not require a service to function.
        pub fn for_test() -> Self {
            Self {
                shared: Default::default(),
                config: Default::default(),
                service: Addr::dummy(),
                project_changes: broadcast::channel(999_999).0,
            }
        }

        /// Sets the project state for a project.
        ///
        /// This can be used to emulate a project cache update in tests.
        pub fn test_set_project_state(&self, project_key: ProjectKey, state: ProjectState) {
            let is_pending = state.is_pending();
            self.shared.test_set_project_state(project_key, state);
            if is_pending {
                let _ = self
                    .project_changes
                    .send(ProjectChange::Evicted(project_key));
            } else {
                let _ = self.project_changes.send(ProjectChange::Ready(project_key));
            }
        }

        /// Returns `true` if there is a project created for this `project_key`.
        ///
        /// A project is automatically created on access via [`Self::get`].
        pub fn test_has_project_created(&self, project_key: ProjectKey) -> bool {
            self.shared.test_has_project_created(project_key)
        }

        /// The amount of fetches triggered for projects.
        ///
        /// A fetch is triggered for both [`Self::get`] and [`Self::fetch`].
        pub fn test_num_fetches(&self) -> u64 {
            self.service.len()
        }
    }
}