# @cats-cradle/message-broker > An API for publishing and receiving async messages Latest version **1.0.0** (published 2023-03-12) · 0 weekly downloads ## Install ```sh npm install @cats-cradle/message-broker pnpm add @cats-cradle/message-broker yarn add @cats-cradle/message-broker bun add @cats-cradle/message-broker ``` Provides the command `app`. ## Health **Score 20/100 (F)** — status: abandoned. Positive: esm support; no vulnerabilities. Warnings: low downloads; no types. Negative: abandoned; low maintenance score. ## Facts | | | |---|---| | Version | 1.0.0 | | Published | 2023-03-12 | | First published | 2023-03-12 | | Weekly downloads | 0 | | TypeScript types | none | | Module format | ESM + CommonJS | | Dependencies | 29 | | Unpacked size | 158.8 KB | | Known vulnerabilities | 0 (+13 in 7 direct dependencies) | | Install scripts | no | | Maintainers | hxtree | ## Links - npm: https://www.npmjs.com/package/@cats-cradle/message-broker - npm.io page: https://npm.io/package/@cats-cradle/message-broker ## Dependencies (29) - [rxjs](https://npm.io/package/rxjs.md) 7.5.6 - [uuid](https://npm.io/package/uuid.md) ~9.0.0 - [lodash](https://npm.io/package/lodash.md) ~4.17.21 - [express](https://npm.io/package/express.md) 4.18.2 - [mongoose](https://npm.io/package/mongoose.md) ~6.9.1 - [aws-lambda](https://npm.io/package/aws-lambda.md) 1.0.7 - [handlebars](https://npm.io/package/handlebars.md) ~4.7.7 - [node-cache](https://npm.io/package/node-cache.md) 5.1.2 - [@nestjs/core](https://npm.io/package/@nestjs/core.md) 9.2.1 - [html-to-text](https://npm.io/package/html-to-text.md) ~9.0.4 - [@nestjs/common](https://npm.io/package/@nestjs/common.md) 9.2.1 - [@nestjs/config](https://npm.io/package/@nestjs/config.md) 2.2.0 - [@nestjs/swagger](https://npm.io/package/@nestjs/swagger.md) ~6.1.3 - [class-validator](https://npm.io/package/class-validator.md) 0.13.2 - [@nestjs/mongoose](https://npm.io/package/@nestjs/mongoose.md) 9.2.1 - [@nestjs/terminus](https://npm.io/package/@nestjs/terminus.md) 9.1.1 - [reflect-metadata](https://npm.io/package/reflect-metadata.md) 0.1.13 - [class-transformer](https://npm.io/package/class-transformer.md) 0.5.1 - [@aws-sdk/client-s3](https://npm.io/package/@aws-sdk/client-s3.md) ~3.287.0 - [source-map-support](https://npm.io/package/source-map-support.md) ~0.5.21 - [@aws-sdk/client-ses](https://npm.io/package/@aws-sdk/client-ses.md) ~3.279.0 - [aws-sdk-client-mock](https://npm.io/package/aws-sdk-client-mock.md) ~2.1.0 - [aws-serverless-express](https://npm.io/package/aws-serverless-express.md) ~3.4.0 - [@cats-cradle/constructs](https://npm.io/package/@cats-cradle/constructs.md) 0.0.1 - [@cats-cradle/base-nodejs](https://npm.io/package/@cats-cradle/base-nodejs.md) 1.0.2 - [@nestjs/platform-express](https://npm.io/package/@nestjs/platform-express.md) 9.3.9 - [@vendia/serverless-express](https://npm.io/package/@vendia/serverless-express.md) 4.8.2 - [@cats-cradle/nestjs-modules](https://npm.io/package/@cats-cradle/nestjs-modules.md) 0.2.0 - [@cats-cradle/validation-schemas](https://npm.io/package/@cats-cradle/validation-schemas.md) 0.2.2 ## Recent versions - 1.0.0 (latest) — 2023-03-12 ## README # @cats-cradle/message-broker This is a “Pub/Sub Message Broker”. It enables async communication between microservices to provide loosely coupling. - SNS topics are deployed with the message broker. - SQS deployments should be owned by consumer. ## Message Categories **Command** Command send a idempotent request to a topic asking subscribers to perform task. The consumer of a command does not inform provide a response to the publisher. The publisher does expect something to occur as a result of the request. > Publisher -> SNS -> SQS -> Consumer **Event** Publish to a SNS topic informing any subscribers that something occurred within a given system. Events published may be significant events that were published only for the purpose of data retention and analytic purposes. > Publisher -> SNS -> SQS -> Consumer **Request** Publish an async message to a single queue letting them know which queue to send a reply to. > Publisher -> SQS -> Consumer -> (SQS -> Publisher) **Reply** In response to a request publish an message to a single queue as request. > (Publisher -> SQS) -> Consumer -> SQS -> Publisher ## TODO - Add a feature to make it easy for apps to publish to events. - Add a feature to make it easy to subscribe to events. - Provision S3 bucket and place all history of all events into. - Save all messages received to bucket. - Indicate whether message was sent only for testing / debugging purposes and should not contaminate history. - Hydration that ties into api-client query might be nifty. - logical id format - decouple topics from broker into global lib ## Documentation - - - --- _Source: https://npm.io/package/@cats-cradle/message-broker · Machine-readable twin of the npm.io package page. Health data is recomputed on every publish._