@amqp-contract/contract

Contract builder for amqp-contract - Define type-safe AMQP messaging contracts.

📖 Full documentation →

Installation

pnpm add @amqp-contract/contract

Quick Start

Recommended: Publisher-First / Consumer-First Patterns

For robust contract definitions with guaranteed consistency, use definePublisherFirst (for events) or defineConsumerFirst (for commands):

import {
  definePublisherFirst,
  defineContract,
  defineExchange,
  defineQueue,
  defineMessage,
} from "@amqp-contract/contract";
import { z } from "zod";

// Event-oriented pattern: publisher doesn't need to know about queues
const ordersExchange = defineExchange("orders", "topic", { durable: true });
const orderMessage = defineMessage(
  z.object({
    orderId: z.string(),
    amount: z.number(),
  }),
);

const { publisher: orderCreatedPublisher, createConsumer: createOrderCreatedConsumer } =
  definePublisherFirst(ordersExchange, orderMessage, { routingKey: "order.created" });

// Multiple queues can consume the same event
const orderQueue = defineQueue("order-processing", { durable: true });
const { consumer, binding } = createOrderCreatedConsumer(orderQueue);

// For topic exchanges, consumers can override with their own pattern
const analyticsQueue = defineQueue("analytics", { durable: true });
const { consumer: analyticsConsumer, binding: analyticsBinding } = createOrderCreatedConsumer(
  analyticsQueue,
  "order.*",
); // Subscribe to all order events

const contract = defineContract({
  exchanges: { orders: ordersExchange },
  queues: { orderQueue, analyticsQueue },
  bindings: { orderBinding: binding, analyticsBinding },
  publishers: { orderCreated: orderCreatedPublisher },
  consumers: {
    processOrder: consumer,
    trackOrders: analyticsConsumer,
  },
});

Benefits:

• ✅ Guaranteed message schema consistency between publishers and consumers
• ✅ Routing key validation and type safety
• ✅ Full type safety with TypeScript inference
• ✅ Event-oriented (publisher-first) and command-oriented (consumer-first) patterns
• ✅ Flexible routing key patterns for topic exchanges

Documentation

📖 Read the full documentation →

• Getting Started Guide
• Publisher-First Pattern
• Consumer-First Pattern
• Complete API Reference

License

MIT