Crate sayiir_persistence 

Persistence layer for workflow execution state.

This crate provides traits and implementations for persisting workflow execution state, enabling distributed execution with checkpoint/restore capabilities.

Trait Hierarchy

The persistence layer is built around focused sub-traits:

• SnapshotStore: Core CRUD for workflow snapshots (5 methods).
• SignalStore: Cancel + pause signal primitives with default composite implementations (3 required + 3 default methods).
• TaskClaimStore: Distributed task claiming (4 methods, opt-in).
• PersistentBackend: Supertrait = SnapshotStore + SignalStore, blanket-implemented so backends never need to impl it directly.

A minimal backend only needs 8 methods (SnapshotStore + 3 SignalStore primitives) to satisfy PersistentBackend.

Example

use sayiir_persistence::{InMemoryBackend, SnapshotStore};
use sayiir_core::snapshot::WorkflowSnapshot;

// Create a backend (could be Redis, PostgreSQL, etc.)
let backend = InMemoryBackend::new();

// Save a snapshot
let snapshot = WorkflowSnapshot::new("instance-123".to_string(), "hash-abc".to_string());
backend.save_snapshot(&snapshot).await?;

// Load it back
let loaded = backend.load_snapshot("instance-123").await?;

Structs

InMemoryBackend

In-memory backend that stores snapshots in a HashMap.

Enums

BackendError

Error type for backend operations.

Traits

PersistentBackend

Supertrait combining SnapshotStore and SignalStore.

SignalStore

Signal storage for cancel and pause workflows.

SnapshotStore

Core snapshot CRUD operations.

TaskClaimStore

Task claiming for distributed multi-worker execution.