README.md

Prisma Client Extension - JSON Field Types

This example shows how to use a Prisma Client extension to provide static and runtime types for a Json field. It uses Zod to parse the field data and infer static TypeScript types.

This example includes a User model with a JSON profile field, which has a sparse structure which may vary between each users. The extension has two parts:

• A result extension that adds a computed profileData field. This field uses the Profile Zod parser to parse the untyped profile field. TypeScript infers the static data type from the parser, so query results have both static and runtime type safety.
• A query extension that parses the profile field of input data for the User model's write methods like create and update.

Caveats

NOTE: Query extensions do not currently work for nested operations. In this example, validations are only run on the top level data object passed to methods such as prisma.user.create(). Validations implemented this way do not automatically run for nested writes.

This extension is provided as an example only. It is not intended to be used in production environments.

Please read the documentation on query extensions and result extensions for more information.

How to use

Prerequisites

• Install Node.js
• Install Docker

1. Download example & install dependencies

Clone this repository:

git clone [email protected]:sbking/prisma-client-extensions.git

Create a .env file and install dependencies:

cd json-field-types
cp .env.example .env
npm install

2. Start the database

Run the following command to start a new Postgres database in a Docker container:

docker compose up -d

3. Run migrations

Run this command to apply migrations to the database:

npx prisma migrate deploy

4. Seed the database

Run the following command to add seed data to the database:

npx prisma db seed

5. Run the dev script

To run the script.ts file, run the following command:

npm run dev