Experiment with parse toml

[bakura10]

Declarative custom data (https://shopify.dev/beta/next-gen-dev-platform/declarative-custom-data-definitions) will allow to create metafield and metaobject definitions directly in a schema. This is, more or less, what this library was doing for the createFromSchema.

However, declarative custom data offers a lot of advantages:

• They don't rqeuire the app to perform check or post-install hook, improving performance
• Schema is kept in sync across all merchants automatically
• Limits are no longer shared among apps

While the feature is not yet available, I think it will be better to wait for a stable release and integrate with this instead. However, because the schema is no longer available as a const, all the TypeScript magic and schema knowledge can't be done anymore.

One approach I'm considering is bundling a CLI tool to generate various things based on the schema found in the TOML file.

Generating types

Considering a schema, this would generate types for the models. For instance considering this:

[metaobjects.app.payment_messages]
name = "Payment Messages"

[metaobjects.app.payment_messages.fields.payment_type]
name = "Payment Type"
type = "single_line_text_field"
required = true

[metaobjects.app.payment_messages.fields.message]
name = "Message"
type = "single_line_text_field"
required = true

This would generate this:

export type PaymentMessages = {
   paymentType: string;
   message: string;
}

Emitting metadata

The library itself needs to know a few things about the schema. This helps knowing how to optimize queries (for instance, knowing if we must fetch references, what are their type... and so on).

To do that, I think the library should also, from this schema, create a global metadata, that could be re-used by the library:

globalThis.__METAOBJECTS_METADATA__ = {
  '$app:payment_messages': {
     fields: {
       payment_type: 'single_line_text_field',
       message: 'single_line_text_field'
    }
  }
}

When we populate a reference, we would therefore now know the type.