We had concerns about the cached values on Redis with the previous two
releases strategy:
First release (this commit):
- Create new encrypted fields in the database.
- Start populating new encrypted fields, read the encrypted fields or
fallback to the plaintext fields.
- Backfill the data removing the plaintext fields to the encrypted
fields.
Second release:
- Remove the virtual attribute (created in step 2).
- Drop plaintext columns from the database (empty columns after
step 3).
We end up with a better strategy only using migration scripts in one
release:
- Pre-deployment migration: Add columns required for storing encrypted
values.
- Pre-deployment migration: Store the encrypted values in the new
columns.
- Post-deployment migration: Remove the old unencrypted columns
This is the plan to encrypt the plaintext tokens:
First release (this commit):
1. Create new encrypted fields in the database.
2. Start populating new encrypted fields, read the encrypted fields or
fallback to the plaintext fields.
3. Backfill the data removing the plaintext fields to the encrypted fields.
Second release:
4. Remove the virtual attribute (created in step 2).
5. Drop plaintext columns from the database (empty columns after step 3).