Environment Variables

Extension comes with built-in support for environment variables via .env file (and alikes).

Take for example, our ChatGPT Template.

See that it expects the EXTENSION_OPENAI_API_KEY environment variable? Create an .env file at the project root so Extension can parse its contents at runtime.

The following file names are supported:

• .env
• .env.local
• .env.defaults
• .env.example

How To Use

1. Create a new file using one of the supported file names at the same folder level as your manifest.json file.
2. In your extension code, add the Node.js pattern of process.env.YOUR_VARIABLE_NAME.

TIP: Environment variables are not supported in the manifest.json file.

See the sample below:

// service_worker.js
const helloWorld = process.env.HELLO_WORLD
console.log(helloWorld)

# .env
HELLO_WORLD=Hello, world!

Will output the following:

// service_worker.js
- const helloWorld = process.env.HELLO_WORLD
+ const helloWorld = "Hello, world!"
console.log(helloWorld)

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