Add a customized bundle

In this tutorial, you'll learn how to do the following tasks:

• Use GraphQL to define the input of your function.
• Build a cart_transform function.

• You've created a Partner account.
• You've created a development store.
• You've created an app that uses Shopify CLI 3.0 or higher, or you've migrated your existing app so that it's compatible with Shopify CLI 3.0 or higher. If you previously installed Shopify CLI, then make sure you're using the latest version.
• You've installed Node.js 16 or higher.
• You've installed your app on the development store.

The following requirements are specific to Rust-based development with Shopify Functions.

• You've installed Rust.

  On Windows, Rust requires the Microsoft C++ Build Tools. Make sure to select the Desktop development with C++ workload when installing the tools.

• You've installed cargo-wasi:

The following example shows an example of the cart input object and the result of the CartTransform function output that groups specific line items from the cart together into a bundled line. The lines might be repriced to offer customers an incentive to purchase a complete bundle.

The process to build a cart_transform function is similar to the process to create a discount function, with two key differences:

• You need to skip the discount React library and related discount React UI code.

• You need to create a cart_transform function instead of a product_discounts function:

In the following example, a metafield reference is used to assign mappings between the bundle parent and components:

You need to request the write_products access scope to run cartTransform mutations in the Shopify Admin API.

1. In shopify.app.toml in the root of your app, add the write_products scope.

2. Start your app.

3. Use the URL provided by the CLI to open and re-install your app. You should be prompted to accept the new access scope permissions in your store.

To activate your function, create a cartTransform object on the store where you installed your app. You can do this using the cartTransformCreate GraphQL mutation.

1. Install the Shopify GraphiQL app on your store. If you've already installed GraphiQL, then you should do so again to select the necessary access scopes for cartTransform.

   Make sure to select the write_products access scopes for the Admin API.

2. Find the ID of your deployed function in the .env file at the root of your app. Your function's ID is the value of the BUNDLE_CART_TRANSFORM_ID environment variable that's defined in the .env file.

3. Run the following mutation. Replace YOUR_FUNCTION_ID_HERE with the ID of your function:

   You should receive a GraphQL response that includes the ID of the new cartTransform object.

• Learn how to build a user interface for bundles in the Shopify admin.
• Learn how to use variables in your input query.