user20230119
How do you undo mix ash.codegen?
I added an attribute to my resource with allow_nil? false.
I ran mix ash.codegen add_entity_path and got resource_snapshots and migrations.
I get this error when running mix ash.migrate.
17:52:16.239 [info] alter table entities
** (Postgrex.Error) ERROR 23502 (not_null_violation) column "path" of relation "entities" contains null values
I tried changing allow_nil? true and ran mix ash.codegen add_entity_path_null, but I still get the same error.
Do I just delete the last two resource_snapshots and the migrations before running mix ash.codegen again?
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vasspilka
I think this mistake comes from the Database. Basically you have at least 1 row in the DB where the attribute is has a
nilvalue. You have to delete those recordszachdaniel
Correct. You can, however if you want, undo the migrations as you described. We’re working on a tool for generating migrations that can be easily “undone” with
mix ash.codegen --devthat tags the migrations as dev migrations. Then you can revert the dev migrations and delete them or you can “save” them withmix ash.codegen <a summary of all the changes>.Until then, there is a script you can use to do it based off of the git changes:
trentjones21
How do you revert dev migrations?
I just added a new attribute to a resource and ran
mix ash.codegen –dev. Then when I ran the migration, they failed because of null values in that column. So I then addeddefault: 0to the attribute and ranmix ash.codegen –devagain. It generated a second dev migration on top of the first on that modified the column to add a default value. However the first migration still fails.I just deleted both of those migrations and ran
mix ash.codegen —devagain and it says no changes detected. So I’m thinking I did something wrong and there are now inconsistencies in the snapshot.What is the correct way to revert?
trentjones21
Ah, I figured out my problem. I need to delete the
_dev.jsonfiles from the snapshots too. My problem is that I added those files to my .gitignore so it was obvious to me that they were there.