PubSub HTTP Handler

PubSub HTTP Handler is a simple Typescript/Javascript package that solves serving an HTTP endpoint that can consume PubSub messages. It is intended to use with Google Cloud Functions or Google Cloud Run.

This package was built so that when creating microservices that subscribes to a PubSub-topic, we don't have to implement a server or validate the request.

The package utilizes Fastify to serve HTTP.

Quickstart

▶ yarn add pubsub-http-handler

Example

import { createPubSubServer, PubSubHandler } from 'pubsub-http-handler';

interface MyHandler {
  hello: string;
  world: string;
}

const server = async () => {
  const handler: PubSubHandler<MyHandler> = ({ message, data }) => {
    // `message` contains attributes, data (as string), messageId
    // `data` contains a base64 decoded JSON serialized object (type is MyHandler in the example)
    // ...
  };

  const { listen } = await createPubSubServer(handler);
  await listen();
};

We also support fastify-plugin and cloud-functions. See more examples in the examples/ folder.

Read more about configuration here or check out the API documentation

Options

• onError (function, default is undefined). Use to ensure that the function doesn't throw. Warning: Using this option will make the function return 204 regardless.

• parseJson (boolean, default is true). When set to true, uses JSON.parse to parse the data sent through PubSub.

• parser (function, optional). This option can be used to parse data coming from PubSub. The function must return data (this data is passed to the handler, as data). You can optionally throw an exception if the data could not be parsed, which in turn can be caught by onError if you'd like.

We export a function called makePubSubConfig to help with type inference. This is basicly a function that lets you return a function while using parser, which is returned in handler. If you know a way for the types to work without using a function like this, we would love a pull request!

Contributing

We love contributions! 🙏 Bug reports and pull requests are welcome on GitHub.