pglite-prisma-adapter

A Prisma driver adapter for PGlite - the embedded PostgreSQL database for JavaScript.

Overview

This adapter enables you to use Prisma ORM with PGlite, a serverless PostgreSQL database that runs in-process in Node.js applications. PGlite provides a fully SQL-compatible database without the need to run a database server.

Prerequisites

- Node.js ≥ 18
- Prisma CLI installed

Installation

Install the adapter and the PGlite driver:

``bash
npm install pglite-prisma-adapter @electric-sql/pglite
`

Or using yarn:

`bash
yarn add pglite-prisma-adapter @electric-sql/pglite
`

Configuration

$3

Create a .env file in your project root:

`env


Path to the database directory (where PGlite will store its files)


DATABASE_DIR="./some/path"
`

$3

Create a schema.prisma file with the required configuration:

`prisma
// schema.prisma
generator client {
provider = "prisma-client-js"
previewFeatures = ["driverAdapters"]
}

datasource db {
provider = "postgres"
// Note: This URL is required by Prisma but will be ignored when using the adapter
url = "postgresql://localhost:5432/mydb"
}

// Define your models
model User {
id Int @id @default(autoincrement())
email String? @unique(map: "uniq_email") @db.VarChar(255)
name String? @db.VarChar(255)
}
`

Usage

$3

Here's how to set up the adapter and run basic queries:

`js
import { PGlite } from "@electric-sql/pglite";
import { PrismaPGlite } from "pglite-prisma-adapter";
import { PrismaClient } from "@prisma/client";
import "dotenv/config";

// Initialize PGlite client with the database directory
const client = new PGlite(process.env.DATABASE_DIR);

// Initialize the PGlite adapter for Prisma
const adapter = new PrismaPGlite(client);

// Create Prisma client with the adapter
const prisma = new PrismaClient({ adapter });

async function main() {
// Create a new user
const user = await prisma.user.create({
data: {
email: "user@example.com",
name: "Example User",
},
});
console.log("Created user:", user);

// Query all users
const users = await prisma.user.findMany();
console.log("All users:", users);
}

main()
.catch(console.error)
.finally(() => prisma.$disconnect());
`

$3

PGlite adapter supports Prisma transactions:

`js
import { PGlite } from "@electric-sql/pglite";
import { PrismaPGlite } from "pglite-prisma-adapter";
import { PrismaClient } from "@prisma/client";
import "dotenv/config";

const client = new PGlite(process.env.DATABASE_DIR);
const adapter = new PrismaPGlite(client);
const prisma = new PrismaClient({ adapter });

async function main() {
try {
// This transaction will fail because both operations create users with the same email
await prisma.$transaction([
prisma.user.create({
data: {
email: "duplicate@example.com",
name: "User 1",
},
}),
prisma.user.create({
data: {
email: "duplicate@example.com", // Same email, will cause a unique constraint violation
name: "User 2",
},
}),
]);
} catch (error) {
console.log("Transaction failed as expected:", error.message);

// This transaction will succeed
const result = await prisma.$transaction([
prisma.user.create({
data: {
email: "user1@example.com",
name: "User 1",
},
}),
prisma.user.create({
data: {
email: "user2@example.com",
name: "User 2",
},
}),
]);

console.log("Successful transaction:", result);
}
}

main()
.catch(console.error)
.finally(() => prisma.$disconnect());
`

Schema Management

PGlite adapter supports Prisma Early Access migration commands, similar to Cloudflare D1 and Turso/LibSQL adapters.

$3

Create a prisma.config.ts file in your project root:

`typescript
// prisma.config.ts
import path from "node:path";
import type { PrismaConfig } from "prisma";
import { PGlite } from "@electric-sql/pglite";
import { PrismaPGlite } from "pglite-prisma-adapter";
import "dotenv/config";

type Env = {
DATABASE_DIR: string;
};

export default {
earlyAccess: true,
schema: path.join("prisma", "schema.prisma"),
migrate: {
async adapter(env) {
const client = new PGlite({ dataDir: env.DATABASE_DIR });
return new PrismaPGlite(client);
},
},
studio: {
async adapter(env) {
const client = new PGlite({ dataDir: env.DATABASE_DIR });
return new PrismaPGlite(client);
},
},
} satisfies PrismaConfig;
`

$3

With the configuration above, you can use these Prisma commands:

| Command | Description |
| ------------------------- | ------------------------------------------------------------ |
| npx prisma db push | Updates your database schema based on your Prisma schema |
| npx prisma db pull | Introspects your database and updates your Prisma schema |
| npx prisma migrate diff | Shows the difference between your database and Prisma schema |
| npx prisma studio | Opens Prisma Studio to interact with your database |

> Note: Support for prisma migrate dev and prisma migrate deploy` is planned for future updates.

Limitations

- This adapter supports Prisma Client for all CRUD operations
- Prisma migrations are supported via Early Access commands
- Some advanced Prisma features may not be fully supported yet

Examples

For more detailed examples, check the examples directory in the PGlite repository.

Credits

This adapter is based on:

- @tidbcloud/prisma-adapter
- @prisma/adapter-pg

License

MIT