Spike: Consider creating a transformer plugin

[JanLenoch]

Expected result

The JS SDK allows the developer to define so called link resolvers and rich text resolvers. These are methods that operate on Kentico Cloud Rich text elements and produce HTML with hyperlinks and embedded content items.

The source plugin currently builds the _nodes sibling GraphQL properties that contain GraphQL links to content items in a given Rich text element. It also lacks the support for creating (or enriching) the _nodes sibling property based on links. It doesn't do any transformation of the rich text element HTML data.

Such a transformation should be dealt with separately using a Gatsby transformer plugin.

Find out:

• what it takes to create a transformer plugin that transforms links and content items in Rich text
• if the resolvers could be written by developers using the same notation as the JS SDK uses

Also, Gatsby have recently updated their best practice and recommend doing any "enhancement" of source nodes via a transformer plugin (not through a source plugin).

Therefore, consider moving the code that creates the _nodes sibling properties into the new transformer plugin.

Resources

• Resolving URL slugs (links) in JS SDK
• Resolving content items and components in Rich text fields in JS SDK

[Simply007]

Just adding showcase, how does the resolution looks like:

links: object containing properties by its ID
modular content: an array with id'S for the items

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[Simply007]

This feature is already implemented in v3 and described in Readme.