Event Store Invariant Checker

This project enables generic invariant checking via two phase commit in event store

Usage

Run the container such that it can access your event store. Then you can write __InvariantCheckRequested events to the __async_invariant stream.

InvariantCheckRequested

example

import { EventStoreDBClient, jsonEvent, NO_STREAM } from '@eventstore/db-client'

const userId = uuid()
const eventId = uuid()
const invariantCheckRequested = {
  type: '__InvariantCheckRequested',
  id: eventId,
  data: {
    invariant: {
      category: 'UserEmailReservation',
      value: 'me@example.com',
      type: 'unique',
      entityId: userId,
    },
    resultingEvent: {
      streamId: `User-${userId}`,
      type: 'UserRegistered',
      id: uuid(),
      expectedRevision: NO_STREAM,
      data: {
        userId,
        email: 'me@example.com',
        name: 'Me Me',
      },
    },
  },
  metadata: {
    $correlationId: eventId,
    $causationId: eventId,
  },
}

await client.appendToStream(
  `__async_invariant`,
  jsonEvent(invariantCheckRequested),
  {
    expectedRevision: ANY,
  }
)

How to use

1. Build the docker image

$ docker build -t invariant-checker:local .

2. Run the docker image

$ docker run --rm -it \
  -e ESDB_CONN_STRING="esdb://connectionstring" \
  --name invariant-checker \
  invariant-checker:local

3. Start sending events!