Encrypt integration - alternative approach

[svendecabooter]

Alternative, simplified approach for integrating the field_encrypt module with the Encrypt module:

• removes the FieldEncryptMap logic altogether - we assume each field has properties that can encrypted by the Encrypt service. Perhaps this will need some extra validation or documentation, since it moves responsibility a bit more to the end user (but avoids the limitations of fixed field mappings)
• the field storage form now has 3 settings
  • whether to encrypt the field (checkbox)
  • which properties to encrypt (the "value" property in most cases - some reasonable defaults are provided)
  • the encryption profile to encrypt with
• upon encrypting fields, we check these settings, and encrypt the selected properties in case encryption was enabled, using the selected encryption profile.

This alternative approach makes the dependency on Encrypt module a bit less open-ended, but I don't think that's necessarily a bad thing...

[svendecabooter]

See also the listing of TODOs in https://github.com/d8-contrib-modules/field_encrypt/pull/19. Perhaps it wasn't the best idea to create a new PR for the flow of the discussion, but it's easier to separate the 2 alternative approaches.

Some extra remarks, which were raised in https://github.com/d8-contrib-modules/field_encrypt/pull/19:

• global properties like ID and other internal properties don't seem to be returned when calling FieldStorageConfig::getPropertyDefinitions(), which the new code does. I only tested for a few common field types for now, so this needs some extra verification, but at first glance it seems we won't have to filter out those, since they aren't returned in the first place.
• base64 encoding seems needed to avoid database errors. The Key module provides base64 encoding / decoding of the keys, but the Encrypt module doesn't encode / decode the encrypted / decrypted strings. Perhaps we can add that as an optional setting in the EncryptService's encrypt() and decrypt() methods, instead of doing the base64 work in field_encrypt. But i'll leave it in for now, until we decided on that.

[nerdstein]

Finished reviewing and left comments.

YES this is much closer to what I was thinking. I really like it.

[svendecabooter]

Added settings form to select default properties per field type, to be used when setting up any field for field encryption. Upon installing the module, sensible defaults are already set for core Drupal field types.

[nerdstein]

This is perfect, I'm merging this in to get this going. I love it