serverpod-offline-sync/SPEC.md

Specification for the implementation

Starting the database

• After the createAll(), call a custom function to inspect the database and list:
  • Each table unique constraints
  • All foreign keys

Check this research for reference.

How to specify which constraint to apply to each case?

Unique can be handled as:

• on_conflict_merge (default)
• on_conflict_overwrite

Foreign keys can be handled as:

• on_fk_deleted_delete_this (default, if cascade delete)
• on_fk_deleted_set_null (default, if optional)
• on_fk_deleted_restore_related

After merge on sync, a callback must be available to check custom rules

There must have an easy way to issue fixes and re-run the merge.

Next:

• Design the registration of constraints in the database.
• Integrate the CRDT for retrieval of changes.
• Integrate the CRDT merge logic.
• Integrate the compensation logic with the merge logic.
• Implement a regenerate process to run after migrations.
• Add pending tests marked as TODO.
• Transform this repo in a monorepo with this package and a Flutter version that provides a custom driftDatabase function that already passes the closure to add the next_hlc_timestamp function to the database.