How to set environment variables with Prisma, Nextjs, and Vercel

Question

Nextjs wants you to use a .env.local file to store env vars. Prisma uses .env

If I use a .env.local file then setting up the Prisma db

datasource db {
  provider = "postgresql"
  url      = env("DATABASE_URL")
}

I get a DATABASE_URL does not exist error.

What's the right way to set up env vars for a Prisma, Nextjs, Vercel app?

Answer 1

You can use dotenv-cli to force loading specific environment file.

1- Install dotenv-cli package

2- create script to run env before prisma migration on your package

"scripts": {
    ...
    "prismaDev": "dotenv -e .env.local prisma migrate dev ",
  }

3- now you can simply run npm run prismaDev