In the previous article, we explored how to create a UI layer for a Nuxt 3 SaaS project. Now, in part two of this series, we’ll focus on building a database layer using Drizzle. Unlike the UI layer, this won’t be a Nuxt 3 layer but rather a standalone npm package.

Setting Up the Database Layer

We will create a simple package named @jiprochazka/db, which will encapsulate our database logic using Drizzle ORM and Postgres.

Step1: Define package.json

$ cd packages
$ mkdir db

Create package.json:

// packages/db/package.json
{
  "name": "@jiprochazka/db",
  "version": "1.0.0",
  "main": "dist/index.js",
  "types": "dist/index.d.ts",
  "scripts": {
    "build": "tsc",
    "dev": "tsc --watch"
  }

Step1: Install Dependencies

Install the necessary dependencies within the db folder. Run the following command:

$ pnpm add dotenv drizzle-orm postgres

For development dependencies, install:

$ pnpm add -D @types/node drizzle-kit tsx typescript

Step 2: Configure TypeScript

Create a tsconfig.json file to configure TypeScript:

// packages/db/tsconfig.json
{
  "compilerOptions": {
    "target": "es2016",
    "module": "commonjs",
    "declaration": true,
    "outDir": "./dist",
    "esModuleInterop": true,
    "forceConsistentCasingInFileNames": true,
    "strict": true,
    "skipLibCheck": true,
    "types": ["node"],
    "moduleResolution": "node",
    "resolveJsonModule": true,
    "allowJs": true
  },
  "include": ["src", "*.ts"],
  "exclude": ["node_modules", "dist"]
}

Step 3: Implement the Database Connection

In the src directory, create an index.ts file with the following content:

// packages/db/src/index.ts
import postgres from "postgres";
import { drizzle } from "drizzle-orm/postgres-js";

export const client = postgres(process.env.DATABASE_URL!);
export const db = drizzle(client);

Explanation:

• We use postgres from postgres to establish a database connection.
• drizzle wraps the Postgres client, providing ORM functionality.
• The database URL is retrieved from environment variables.

Using the Layer

In the project app, add the npm package to the app package.json:

// apps/my-app/package.json
"dependencies": {
    ...
    "~db": "workspace:@jiprochazka/db@*",
}

Now you are ready and the usage is simple (after setting the environment variable, of course):

import { db } from "~db"

const result = await db.select().from(users);

Summary

In this article, we created a standalone npm package for our database layer using Drizzle ORM and Postgres. This package can now be imported and used in any part of our SaaS platform, making the database logic modular and reusable.

Stay tuned!