Codecov Report

Merging #1258 (5e19c8e) into main (d0c1fd6) will decrease coverage by 0.00%.
The diff coverage is 37.50%.

@@            Coverage Diff             @@
##             main    #1258      +/-   ##
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- Coverage   58.46%   58.46%   -0.01%     
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  Files         206      206              
  Lines       25258    25264       +6     
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+ Hits        14768    14771       +3     
- Misses       9395     9398       +3     
  Partials     1095     1095              

A little background here. I originally wrote it this way (or at least tried) because of the uncertainty around how the db type is configured, and a desire for the core db-migration functionality to be as portable as possible. That is, I tried to write it so that it could convert any databases, not just ones specific to Cosmos. Looking back, there were definitely some flaws in that thinking.

Here's where things can get tricky though. There's two places where the db type can be configured that affect different db directories:

1. The db_backend config field.
2. The app_db_backend config field. If this isn't set, it falls back to the db_backend value. This replaced the DBBackend variable that needed to be set during compilation (and didn't fall back or anything).

If I'm remembering correctly, the app_db_backend value defines the application and snapshots dbs, and db_backend defines the rest. Basically, it's possible that not every db is the same type. I wanted the dbmigrator to work on any directory (not specific to data), so I decided it would be best to not hard-code an associate of which db name goes with which configuration parameter. And at the time I started writing it, the dbmigrator didn't have access to that DBBackend variable since it's compiled separately.

Additionally, it's not uncommon to get a data dir, but not the configs associated with it. So I often didn't know what type it was.