Delete data when basic data streams are deleted. Fixes #488

[mstenta]

See #488

[paul121]

It seems that we had this when we had a separate legacy data stream bundle, but the hook_data_stream_delete implementation got dropped with this commit: e528813

We should add a test for this so we don't forget it in the future.

This PR is nearly identical to the original code though, so LGTM otherwise!

function farm_sensor_listener_data_stream_delete(DataStreamInterface $data_stream) {

  // Remove all legacy listener data provided by the data stream.
  if ($data_stream->bundle() == 'legacy_listener') {
    \Drupal::database()->delete('data_stream_legacy')
      ->condition('id', $data_stream->id())
      ->execute();
  }
}

[paul121]

Added a test for this!

In the process, noticed that we have the logic for removing references to data streams in the wrong place, it should be in farm_sensor. Moved the logic and added another test for this, but running into the entity reference integrity issue... so I marked the test to be skipped for now, but this still causes our test runner to fail. Gotta run but wanted to push here for now...

[mstenta]

Thanks @paul121! I separated this into two branches...

1. 2.x-delete-data-stream-data with my original commit + your test for deleting data
2. 2.x-data-stream-references with your two commits re: asset reference fields

I'll point to (2) from #485...

Running tests on this PR (2.x-delete-data-stream-data) now... I will merge if it passes.

[mstenta]

Ah tests failed because SQLSTATE[42P01]: Undefined table: 7 ERROR: relation "test36388637asset__data_stream" does not exist - this is probably what you ran into, huh @paul121 :-)

Whelp... I suppose we can just delete that original code from hook_ENTITY_TYPE_delete() (which is causing the test to fail), since we discovered in #485 that it isn't working as intended anyway (and maybe we'll end up taking a different approach to solve that issue, removing the need for that code).

[paul121]

Precisely - that's perfect!