Supporting metabase "Display values" for foreign keys (/api/field/XXX/dimension)

[janmechtel]

In metabase admin > Table Metadata one can choose to display a value from the

Display values
Choose to show the original value from the database, or have this field display associated or custom information.

If metabase know of the columns relation to another table via foreign/primary key...
... there are usually two options:

1. Use Original Value - which display for example the ID (this is usually the metabase type Entity Key in the Primary Key's table)
2. Use Foreign key - which shows a second dropdown from where one can chose which field to display, it defaults to the field that has the metabase type Entity Name

Ideally I'd like to set this "dimension" via the .yml:

          metabase.semantic_type: type/FK
          metabase.fk_target_table: schema.entities
          metabase.fk_target_field: entity_id
          metabase.display_field: entity_name 

This would indicate to display the column called entity_name .

This would require a POST https://metabase.domain.com/api/field/20000/dimension with the payload:

{"type":"external","name":"Name","human_readable_field_id":25000}

Removing reqiores a DELETE toward /api/field/20000/dimension

Questions:

1. Whether this functionality already exists? I suspect not because I didn't find any code mentioning dimension
2. Would you consider giving me pointers how to add this?

[gouline]

Does not currently exist. Have a look at existing fields (like display_name) for how to add it to the metadata. Since it requires a separate API call though, you'll have to figure out where that lives against the existing calls.