SLIP Sockets

This library and CDK project creates a websocket server similar to PUSHPIN and the GRIP protocol. It will make HTTP requests to your backend app in response to events (connection, disconnection and text frames). It manages a pub sub infrastructure so you can publish events to all connected websockets, and it has a client library for communication.

It takes a slightly annoying api from api gateway and makes it straight forward to use. You can now queue events to be sent on connection, have connection metadata and a pub sub system that's straightforward to use.

• See the slip-sockets README for the client library.
• See the @slip-sockets/stack README for the CDK project.

// In you application callback handler

const wsPublisher = new SlipSocketPublisher({ controlApi, jwtSecret })

export async function POST(request: Request) {
  const connection = await wsPublisher.parseRequest(request)
  if (!connection) {
    return new Response('Invalid token', {
      status: 403,
    })
  }

  for (const event of connection.inEvents) {
    if (event.type === 'OPEN') {
      connection.accept()
      connection.subscribe('cool-channel')
      connection.publishText('cool-channel', 'New connection has joined!')
      connection.sendText('Welcome to the cool channel, be nice or get out')
      continue
    }
    if (event.type ==='CLOSE') {
      connection.publish('cool-channel', 'A Connection has left')
      continue
    }

    if (event.type === 'TEXT') {
      if (event.data === 'quit') {
        connection.close()
        continue
      }
      connection.publishText('cool-channel', `${event.connectionId} says ${event.text}`)
      continue
    }

    assertUnreachable(event)
  }

  return connection.endResponse()
}

Publishing

• run pnpm changeset to create a new changeset file in your PR. This will prompt you for the packages you want to bump versions for and the type of bump (major, minor, patch). Only bump the packages you have made changes to.
• A github action will run pnpm changeset version and keep a PR up to date with the next versions of the packages previously specified with pnpm changeset (and any dependents of those) and update the changelog files.
• Merge the PR and the release workflow will run pnpm publish -r. Which will publish all packages that have bumped versions not yet present in the registry.