Installing NPM Packages in Supabase Edge Functions If you're familiar with Supabase Edge Functions, you may know that installing npm packages is not as straightforward as in a typical Node.js or Express application. However, there are several methods to include npm packages in Supabase Edge Functions. In this guide, I'll demonstrate how to use the import_map.json file to achieve this.

Ensure Docker is installed on your machine.

Choose your directory and run the following command:

npx supabase init

This will create a supabase folder in your directory.

Run the following command to start the project:

npx supabase start

This process may take a few minutes as it pulls Docker images and starts the containers.

Open the directory in your favorite code editor and run the following command to create a new Supabase Edge Function:

npx supabase functions new <your-function-name>

This will create a folder with the name of your function inside the functions directory.

You can install any npm package. For this example, we'll install LangChain packages to create a basic RAG pipeline.

Create a file named import_map.json in your functions folder and add the following JSON block:

{
  "imports": {
    "@supabase/supabase-js": "npm:@supabase/supabase-js@2.43.1",
    "langchain/": "https://esm.sh/langchain@0.2.0/",
    "@langchain/openai/": "https://esm.sh/@langchain/openai@0.0.28/",
    "@langchain/core/": "https://esm.sh/@langchain/core@0.1.62/",
    "@langchain/community/": "https://esm.sh/@langchain/community@0.0.56/"
  }
}

If you want to use submodules of an npm package, ensure you add a / at the end of the package name. For reference, see the import of @supabase/supabase-js and the remaining langchain packages.

Ensure your project is linked with your Supabase cloud project.

To deploy your edge function to Supabase, run the following command:

npx supabase functions deploy

This command will deploy all functions.

To deploy a specific function, use:

npx supabase functions deploy <function-name>