Stores Overview

Stores persist saga state to databases.

Choosing a Store

Store	Best For	Features
PostgreSQL	General purpose	ACID, JSON support
MySQL	MySQL shops	Wide compatibility
SQL Server	Microsoft stack	Enterprise features
MongoDB	Document-oriented	Flexible schema
DynamoDB	AWS serverless	Auto-scaling
Redis	High performance	TTL support
SQLite	Local development	Zero config
Prisma	ORM users	Type-safe queries
In-Memory	Testing	No persistence

Store Interface

All stores implement:

interface SagaStore<TState extends SagaState> {
  getById(sagaName: string, sagaId: string): Promise<TState | null>;
  getByCorrelationId(sagaName: string, correlationId: string): Promise<TState | null>;
  insert(sagaName: string, correlationId: string, state: TState): Promise<void>;
  update(sagaName: string, state: TState, expectedVersion: number): Promise<void>;
  delete(sagaName: string, sagaId: string): Promise<void>;
}

Basic Usage

import { PostgresSagaStore } from '@saga-bus/store-postgres';

const store = new PostgresSagaStore({
  connectionString: process.env.DATABASE_URL,
});

const bus = createBus({
  transport,
  store,
  sagas: [{ definition: orderSaga }],
});

Schema Management

Most SQL stores provide schema helpers:

import { createSchema, getSchemaSql } from '@saga-bus/store-postgres';

// Create tables programmatically
await createSchema(pool);

// Or get SQL for manual migration
const sql = getSchemaSql();

Shared vs Per-Saga

// Shared store (recommended)
const bus = createBus({
  store: sharedStore,
  sagas: [{ definition: saga1 }, { definition: saga2 }],
});

// Per-saga stores
const bus = createBus({
  sagas: [
    { definition: saga1, store: store1 },
    { definition: saga2, store: store2 },
  ],
});