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PostgreSQL Store

Production-ready store using PostgreSQL.

Installation​

npm install @saga-bus/store-postgres pg

Basic Usage​

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

const store = new PostgresSagaStore({
  connectionString: 'postgres://user:pass@localhost:5432/mydb',
});

Configuration​

OptionTypeDefaultDescription
connectionStringstringRequiredPostgreSQL connection string
poolPool-Existing pg Pool instance
tableNamestring'sagas'Table name
schemastring'public'Schema name

Schema Setup​

Automatic​

import { createSchema } from '@saga-bus/store-postgres';
import { Pool } from 'pg';

const pool = new Pool({ connectionString: process.env.DATABASE_URL });
await createSchema(pool);

Manual Migration​

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

const sql = getSchemaSql();
// Add to your migration tool

SQL Schema​

CREATE TABLE IF NOT EXISTS sagas (
  saga_name VARCHAR(255) NOT NULL,
  saga_id UUID NOT NULL,
  correlation_id VARCHAR(255) NOT NULL,
  version INTEGER NOT NULL DEFAULT 1,
  state JSONB NOT NULL,
  is_completed BOOLEAN NOT NULL DEFAULT FALSE,
  created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
  updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
  PRIMARY KEY (saga_name, saga_id)
);

CREATE INDEX idx_sagas_correlation ON sagas (saga_name, correlation_id);
CREATE INDEX idx_sagas_completed ON sagas (saga_name, is_completed);

Full Example​

import { createBus } from '@saga-bus/core';
import { RabbitMqTransport } from '@saga-bus/transport-rabbitmq';
import { PostgresSagaStore, createSchema } from '@saga-bus/store-postgres';
import { Pool } from 'pg';

const pool = new Pool({
  connectionString: process.env.DATABASE_URL,
  max: 20,
});

// Create schema if needed
await createSchema(pool);

const store = new PostgresSagaStore({ pool });
const transport = new RabbitMqTransport({ url: process.env.RABBITMQ_URL });

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

await bus.start();

Docker Setup​

services:
  postgres:
    image: postgres:16
    environment:
      POSTGRES_DB: sagas
      POSTGRES_USER: postgres
      POSTGRES_PASSWORD: postgres
    ports:
      - "5432:5432"