Detailed Capabilities Configuration for Custom Power BI Tree-Type Visual with Parent-Child Relationships and Data Retrieval

Question

I'm working on developing a custom Power BI visual in the form of a tree-type structure, and I'm facing challenges when trying to define and configure the capabilities for my specific case. The main objective is to model parent-child relationships between two tables, even though they might have different column names.

Context:

I have two data tables. Despite having distinct column names, there are common values that I want to use to establish a parent-child relationship between them. The intention is to visualize the data in such a way that one table acts as the "parent" and displays information, while the other serves as its "child" with related data entries.

After matching a parent with its child, I wish to fetch specific data from the row of that matched child. To accomplish this, I intend to have another field in the capabilities where I can specify which columns to retrieve data from, once the matching between parent and child has occurred.

Capabilities Configuration: In my capabilities.json, I've been experimenting with the dataViewMappings property. However, I've faced the following issues:

I'm only managing to retrieve one column at a time into my visual. I've tried using both table and matrix structures in dataViewMappings, but neither seems to work as expected.

Here's a basic structure of what I've tried:

json

{
  "dataRoles": [...],
  "dataViewMappings": [
    {
      "table": {
        "rows": {
          "select": [...],
          "for": [...]
        }
      }
    }
  ]
}

I feel like I'm missing something or perhaps not structuring the capabilities correctly.

Has anyone tackled a similar challenge or could guide me on the nuances of setting up capabilities.json for parent-child table relationships in Power BI, especially when wanting to fetch data from specific columns post-match? Detailed examples or resources would be invaluable.

Thank you in advance!