Crate ic_timers 

Observable and recovery-aware timer primitives for Internet Computer canisters.

ic-timers is a higher-level wrapper around ic-cdk-timers, which remains the provider that arms and clears platform timers. This crate adds bounded coordination, scheduling, and observation above it.

The 0.3 runtime executes Once, after-completion, and pre-armed synchronous watchdog callbacks through one volatile canister-local registry. Consumers retain durable application authority and synchronously reconstruct retained registrations during their existing lifecycle hooks. Transient remove-on-stop callbacks use direct registration. Registration capabilities can observe exact armed provider-wakeup ownership without making snapshots or observations into scheduling authority.

Re-exports

pub use schedule::ScheduleError;

pub use schedule::TimerCadence;

pub use schedule::TimerDirective;

pub use schedule::TimerSchedule;

pub use snapshot::DeclarationLifetime;

pub use snapshot::InactiveReason;

pub use snapshot::MAX_TIMER_LABEL_BYTES;

pub use snapshot::MeasurementSummary;

pub use snapshot::OrdinaryRuntimeStateSnapshot;

pub use snapshot::TimerCompletion;

pub use snapshot::TimerCompletionOutcome;

pub use snapshot::TimerControlFailure;

pub use snapshot::TimerCounters;

pub use snapshot::TimerDirectiveSnapshot;

pub use snapshot::TimerEpoch;

pub use snapshot::TimerIdentity;

pub use snapshot::TimerIdentityError;

pub use snapshot::TimerIdentityField;

pub use snapshot::TimerLabel;

pub use snapshot::TimerLabelError;

pub use snapshot::TimerLastOutcome;

pub use snapshot::TimerObservabilitySnapshot;

pub use snapshot::TimerOutcomeSnapshot;

pub use snapshot::TimerPerformance;

pub use snapshot::TimerPolicy;

pub use snapshot::TimerProcessCondition;

pub use snapshot::TimerRegistrationStatus;

pub use snapshot::TimerRunResult;

pub use snapshot::TimerRuntimeStateSnapshot;

pub use snapshot::TimerSchedulingMode;

pub use snapshot::TimerSnapshot;

pub use snapshot::WatchdogAttemptSnapshot;

pub use snapshot::WatchdogAttemptStatus;

pub use snapshot::WatchdogDecision;

pub use snapshot::WatchdogRunResult;

pub use snapshot::WatchdogRuntimeStateSnapshot;

Modules

schedule

Checked cadence and scheduling decisions.

snapshot

Provider-neutral identity and coherent canonical snapshot values.

Structs

AfterCompletionRegistration

Opaque non-clone claim for one after-completion callback.

OnceRegistration

Opaque non-clone claim for one registered Once callback.

TimerContext

Delegated control capability scoped to one exact consumer-work attempt.

WatchdogRegistration

Opaque non-clone claim for one pre-armed watchdog callback.

Enums

RegisterError

Failure to claim one canonical timer identity.

TimerError

Failure from the canister-local timer runtime API.

TimerReconcileState

Desired volatile scheduling state during synchronous lifecycle reconciliation.

Constants

MAX_TIMER_REGISTRATIONS

Maximum declarations owned by one canonical registry.

Functions

consecutive_expected_failures

Return functional expected-failure state by identity without a full inventory.

initialize_runtime

Initialize the volatile canister-local runtime once for this Wasm instance.

reconcile_after_completion

Reconstruct or reconcile one after-completion declaration synchronously.

reconcile_once

Reconstruct or reconcile one Once declaration synchronously.

reconcile_watchdog

Reconstruct or reconcile one watchdog declaration synchronously.

register_after_completion

Register one asynchronous fixed-cadence after-completion callback.

register_once

Register one asynchronous Once callback without scheduling it.

register_watchdog

Register one synchronous pre-armed watchdog callback without scheduling it.

timer_snapshot

Return one coherent inert snapshot by identity.

timer_snapshots

Return the complete bounded inventory in deterministic identity order.