Skip to content

amqp-contractType-safe contracts for AMQP/RabbitMQ

End-to-end type safety ยท Runtime validation ยท Reliable retry patterns

amqp-contract

Quick Example โ€‹

Define your contract once โ€” get type safety everywhere:

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

const ordersExchange = defineExchange("orders", "topic", { durable: true });
const ordersDlx = defineExchange("orders-dlx", "topic", { durable: true });
const orderProcessingQueue = defineQueue("order-processing", {
  deadLetter: { exchange: ordersDlx },
  retry: { mode: "ttl-backoff" }, // Automatic retry with exponential backoff
});

const orderMessage = defineMessage(
  z.object({
    orderId: z.string(),
    amount: z.number(),
  }),
);

// Event pattern: publisher broadcasts, consumers subscribe
const orderCreatedEvent = defineEventPublisher(ordersExchange, orderMessage, {
  routingKey: "order.created",
});

// Compose contract - configs go directly, bindings auto-generated
export const contract = defineContract({
  exchanges: { orders: ordersExchange, ordersDlx },
  queues: { orderProcessing: orderProcessingQueue },
  publishers: {
    // EventPublisherConfig โ†’ auto-extracted to publisher
    orderCreated: orderCreatedEvent,
  },
  consumers: {
    // EventConsumerResult โ†’ auto-extracted to consumer + binding
    processOrder: defineEventConsumer(orderCreatedEvent, orderProcessingQueue),
  },
});
typescript
import { TypedAmqpClient } from "@amqp-contract/client";
import { contract } from "./contract";

const client = await TypedAmqpClient.create({
  contract,
  urls: ["amqp://localhost"],
}).resultToPromise();

await client.publish("orderCreated", {
  orderId: "ORD-123", // โœ… TypeScript knows!
  amount: 99.99,
});
typescript
import { TypedAmqpWorker } from "@amqp-contract/worker";
import { Future, Result } from "@swan-io/boxed";
import { contract } from "./contract";

const worker = await TypedAmqpWorker.create({
  contract,
  handlers: {
    processOrder: ({ payload }) => {
      console.log(payload.orderId); // โœ… Fully typed!
      return Future.value(Result.Ok(undefined));
    },
  },
  urls: ["amqp://localhost"],
}).resultToPromise();

Released under the MIT License.