taskvisor 0.4.0

Task supervisor for Tokio: restarts background tasks on failure with exponential backoff and jitter, graceful shutdown, and lifecycle events
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

//! Controller submission errors.

use thiserror::Error;

/// Error returned by controller submission methods.
#[non_exhaustive]
#[derive(Error, Debug, Clone, Copy, PartialEq, Eq)]
pub enum ControllerError {
    /// The supervisor was built without a controller.
    ///
    /// Enable the `controller` feature and configure the supervisor with `with_controller(...)` before using controller submission methods.
    #[error("controller not configured")]
    NotConfigured,

    /// The controller intake queue is full.
    ///
    /// Returned only by `try_submit`.
    /// Use async `submit` or `submit_and_watch` if the caller should wait for intake capacity instead of failing fast.
    #[error("submission queue full")]
    Full,

    /// The controller intake channel is closed.
    ///
    /// This usually means the controller loop has stopped or the supervisor is shutting down.
    #[error("controller channel closed")]
    Closed,

    /// The controller loop was started more than once.
    ///
    /// This is an internal lifecycle guard. Normal submission APIs do not return this variant.
    #[error("controller already started")]
    AlreadyStarted,
}

impl ControllerError {
    /// Returns a short stable label for logs and metrics.
    ///
    /// The label is not the same as `Display`.
    /// It is intended for machine-readable dimensions.
    #[must_use]
    pub fn as_label(&self) -> &'static str {
        match self {
            ControllerError::AlreadyStarted => "controller_already_started",
            ControllerError::NotConfigured => "controller_not_configured",
            ControllerError::Closed => "controller_closed",
            ControllerError::Full => "controller_full",
        }
    }
}