Astro

Introduction

Prisma ORM offers type-safe database access, and Astro is built for performance. Together with Prisma Postgres, you get a fast, content-first stack with zero cold starts and end-to-end speed.

In this guide, you'll learn to integrate Prisma ORM with a Prisma Postgres database in an Astro project from scratch. You can find a complete example of this guide on GitHub.

Prerequisites

• Node.js 20+
• Astro VSCode extension (recommended)

1. Set up your project

Create a new Astro project:

npx create-astro@latest

Navigate into the newly created project directory:

cd astro-prisma

2. Install and Configure Prisma

2.1. Install dependencies

To get started with Prisma, you'll need to install a few dependencies:

npm install prisma tsx @types/pg --save-dev

npm install @prisma/client @prisma/adapter-pg dotenv pg

Once installed, initialize Prisma in your project:

npx prisma init --db --output ../prisma/generated

This will create:

• A prisma/ directory with a schema.prisma file
• A prisma.config.ts file for configuring Prisma
• A .env file with a DATABASE_URL already set

2.2. Define your Prisma Schema

In the prisma/schema.prisma file, add the following models and change the generator to use the prisma-client provider:

generator client {
  provider   = "prisma-client"
  output     = "../prisma/generated"
}

datasource db {
  provider = "postgresql"
}

model User { 
  id    Int     @id @default(autoincrement()) 
  email String  @unique
  name  String?
  posts Post[]
} 
model Post { 
  id        Int     @id @default(autoincrement()) 
  title     String
  content   String?
  published Boolean @default(false) 
  authorId  Int
  author    User    @relation(fields: [authorId], references: [id]) 
} 

This creates two models: User and Post, with a one-to-many relationship between them.

2.3 Add dotenv to prisma.config.ts

To get access to the variables in the .env file, they can either be loaded by your runtime, or by using dotenv. Include an import for dotenv at the top of the prisma.config.ts

import "dotenv/config"; 
import { defineConfig, env } from "prisma/config";
export default defineConfig({
  schema: "prisma/schema.prisma",
  migrations: {
    path: "prisma/migrations",
  },
  datasource: {
    url: env("DATABASE_URL"),
  },
});

2.4. Run migrations and generate Prisma Client

Now, run the following command to create the database tables:

npx prisma migrate dev --name init

Then generate Prisma Client:

npx prisma generate

2.5. Seed the database

Let's add some seed data to populate the database with sample users and posts.

Create a new file called seed.ts in the prisma/ directory:

import { PrismaClient, Prisma } from "../prisma/generated/client";
import { PrismaPg } from "@prisma/adapter-pg";

const adapter = new PrismaPg({
  connectionString: process.env.DATABASE_URL!,
});

const prisma = new PrismaClient({
  adapter,
});

const userData: Prisma.UserCreateInput[] = [
  {
    name: "Alice",
    email: "alice@prisma.io",
    posts: {
      create: [
        {
          title: "Join the Prisma Discord",
          content: "https://pris.ly/discord",
          published: true,
        },
        {
          title: "Prisma on YouTube",
          content: "https://pris.ly/youtube",
        },
      ],
    },
  },
  {
    name: "Bob",
    email: "bob@prisma.io",
    posts: {
      create: [
        {
          title: "Follow Prisma on Twitter",
          content: "https://www.twitter.com/prisma",
          published: true,
        },
      ],
    },
  },
];

export async function main() {
  console.log("Starting to seed...");

  for (const u of userData) {
    await prisma.user.upsert({
      where: { email: u.email },
      update: {},
      create: u,
    });
  }

  console.log("Seeding finished.");
}

main()
  .catch((e) => {
    console.error(e);
    process.exit(1);
  })
  .finally(async () => {
    await prisma.$disconnect();
  });

Now, tell Prisma how to run this script by updating your prisma.config.ts:

import "dotenv/config";
import { defineConfig, env } from "prisma/config";
export default defineConfig({
  schema: "prisma/schema.prisma",
  migrations: {
    path: "prisma/migrations",
    seed: `tsx prisma/seed.ts`,
  },
  datasource: {
    url: env("DATABASE_URL"),
  },
});

Run the seed script:

npx prisma db seed

And open Prisma Studio to inspect your data:

npx prisma studio

3. Integrate Prisma into Astro

3.1. Create TypeScript environment definitions

First, create an env.d.ts file in your src directory to provide TypeScript definitions for environment variables:

interface ImportMetaEnv {
  readonly DATABASE_URL: string;
}

interface ImportMeta {
  readonly env: ImportMetaEnv;
}

3.2. Create a Prisma Client

Inside of /src, create a lib directory and a prisma.ts file inside it. This file will be used to create and export your Prisma Client instance.

mkdir src/lib
touch src/lib/prisma.ts

Set up the Prisma client like this:

import { PrismaClient } from "../../prisma/generated/client";
import { PrismaPg } from "@prisma/adapter-pg";

const adapter = new PrismaPg({
  connectionString: import.meta.env.DATABASE_URL,
});

const prisma = new PrismaClient({
  adapter,
});

export default prisma;

3.3. Create an API route

An API route is the best way to fetch data from your database in an Astro app.

Create a new file called api/users.ts in the src/pages directory:

mkdir src/pages/api
touch src/pages/api/users.ts

Now, create a GET route that fetches the Users data from your database, making sure to include each user's Posts by adding them to the include field:

import type { APIRoute } from "astro";
import prisma from "../../lib/prisma";

export const GET: APIRoute = async () => {
  const users = await prisma.user.findMany({
    include: { posts: true },
  });

  return new Response(JSON.stringify(users), {
    headers: { "Content-Type": "application/json" },
  });
};

3.4. Fetch the data from the API route (Recommended Method)

Instead of using fetch() with HTTP requests, Astro recommends importing endpoint functions directly. This approach is more efficient and avoids URL parsing issues.

Start by creating a new type that combines the User and Post models called UserWithPosts:

---
import type { User, Post } from "../../prisma/generated/client"; 
import { GET } from "./api/users.ts"; 
type UserWithPosts = User & { posts: Post[] }; 
const response = await GET(Astro); 
const users: UserWithPosts[] = await response.json(); 
---

<html lang="en">
  <head>
    <meta charset="utf-8" />
    <link rel="icon" type="image/svg+xml" href="/favicon.svg" />
    <meta name="viewport" content="width=device-width" />
    <meta name="generator" content={Astro.generator} />
    <title>Astro + Prisma</title>
  </head>
  <body>
    <h1>Astro + Prisma</h1>
    <ul> // [!code ++]
      {users.map((user: UserWithPosts) => ( 
        <li> // [!code ++]
          <h2>{user.name}</h2> // [!code ++]
          <ul> // [!code ++]
            {user.posts.map((post: Post) => ( 
              <li>{post.title}</li> 
            ))} // [!code ++]
          </ul> // [!code ++]
        </li> 
      ))} // [!code ++]
    </ul> // [!code ++]
  </body>
</html>

3.5. Run your app

Now start your development server to see your Astro app in action:

npm run dev

Open your browser at http://localhost:4321 to see the users and their posts displayed on the page.

Summary

You're done! You've just created an Astro app with Prisma that's connected to a Prisma Postgres database. Below are some next steps to explore, as well as some more resources to help you get started expanding your project.

Next Steps

Now that you have a working Astro app connected to a Prisma Postgres database, you can:

• Extend your Prisma schema with more models and relationships
• Add create/update/delete routes and forms
• Explore authentication and validation
• Enable query caching with Prisma Postgres for better performance

More Info

• Prisma Documentation
• Astro Documentation