@schemeless/event-store-adapter-prisma

Official Prisma adapter for the Schemeless Event Store. This package lets you use a Prisma Client instance as the persistence layer behind @schemeless/event-store, embracing Prisma's schema-first workflow while reusing the existing event sourcing APIs.

Installation

yarn add @schemeless/event-store-adapter-prisma @prisma/client
yarn add -D prisma

Setup

1. Add the EventStoreEntity model to your prisma/schema.prisma file. A ready-to-copy example lives at schema.prisma.example and is also exported from src/schema.prisma.example for programmatic access.
2. Run Prisma migrations to apply the schema to your database:
   • During development: npx prisma migrate dev
   • In production: npx prisma migrate deploy
3. Generate the Prisma Client that this adapter expects:

npx prisma generate

After these steps the generated client will include the eventStoreEntity model used by the adapter.

Usage

import { PrismaClient } from '@prisma/client';
import { makeEventStore } from '@schemeless/event-store';
import { EventStoreRepo } from '@schemeless/event-store-adapter-prisma';

const prisma = new PrismaClient();
const repo = new EventStoreRepo(prisma);

await repo.init(); // ensures the Prisma client is connected

const eventStore = await makeEventStore({
  repo,
});

// Store new events through the Event Store APIs as usual

The adapter never runs migrations or schema updates for you. Make sure your deployment pipeline runs the appropriate prisma migrate or prisma db push commands before the application starts.

API

EventStoreRepo implements the shared IEventStoreRepo interface and exposes the following methods:

• constructor(prismaClient) – Accepts an existing PrismaClient instance so you can share connection pooling with the rest of your application.
• init() – Calls prisma.$connect() to ensure the adapter has an active database connection before persisting events.
• storeEvents(events) – Persists the provided events inside a Prisma interactive transaction, maintaining write ordering.
• getAllEvents(pageSize, startFromId?) – Returns an async iterator that replays events ordered by creation time and identifier.
• resetStore() – Clears all persisted events via deleteMany, useful for tests.