Verify No Changes Command

[justindbaur]

Problem:
I need to be able to create a CI job that can verify that there have been no changes to our database schema without a migration being added for it. So that I can create a PR gate.

Solution:
I would love a command in the dotnet ef CLI to verify no migrations are needed, something like.

dotnet ef migrations verify-no-changes

This would respond with exit code 0 if no migrations are needed and exit code 1 if migrations are needed.

I believe it would essentially just need to gather up operations like here:

efcore/src/EFCore.Design/Migrations/Design/MigrationsScaffolder.cs

Lines 145 to 146 in 702f1ce

	var upOperations = Dependencies.MigrationsModelDiffer
	.GetDifferences(lastModel, Dependencies.Model.GetRelationalModel());

Then it would just check that both lists are empty. I would be more than willing to work on this if the idea is approved.

Alternate Solution:
Add an additional options to dotnet ef migrations add for --ensure-empty so that it will fail when there are operations that are needed and will return with a non-zero exit code.

[ajcvickers]

Duplicate of #26348. Please make sure to vote (👍) for that issue.

[justindbaur]

@ajcvickers Thank you! I tried to find one but my google-fu isn't good enough I guess.