Generating the Client (JavaScript)

Overview

The Prisma client is auto-generated using the prisma1 generate command of the Prisma CLI. One Prisma client connects to exactly one Prisma service.

prisma1 generate reads the information that's specified under the generate root property in your service's prisma.yml.

Configuring generate in prisma.yml

The generate root property accepts a list of objects. Each object has two fields:

• generator: The programming language in which the Prisma client should be generated. Here are the accepted values:

  • typescript-client
  • javascript-client
  • flow-client
  • go-client
• output: The path and name of the file in which the Prisma client should be stored.

Example

As an example, consider the following prisma.yml:

datamodel: datamodel.prisma
endpoint: http://localhost:4466
secret: mysecret42

generate:
  - generator: javascript-client
    output: ./prisma-client/

Running prisma1 generate in the directory where that prisma.yml is located generates a Prisma client in JavaScript and stores the generated files in a directory called prisma-client.

The generated Prisma client is configured to target the endpoint specified in prisma.yml. It also knows the secret so that it can authenticate against your Prisma service when you're using it in your application.

Using environment variables in prisma.yml

Note that you can also reference environment variables in prisma.yml by using the env:-prefix and enclosing them with ${}. For example, if you have an environment variable set that's called MY_SECRET:

datamodel: datamodel.prisma
endpoint: http://localhost:4466
secret: ${env:MY_SECRET}

generate:
  - generator: javascript-client
    output: ./prisma-client/

You can find more info about using environment variables here.

Generated files

Here is an overview of the files that are generated for the JavaScript client:

• index.d.ts: Type definitions for the Prisma client (in TypeScript). The type definitions include representations of your models (from the datamodel) as well as the function signatures for the generated API operations of the Prisma client. Even though it's TypeScript, this file is included in the JavaScript Prisma client to enable auto-completion and other features in your code editor.
• index.js: The Prisma client.
• prisma-schema.js: This file is used by the Prisma client under the hood.