Prune the migration files for Airflow 3#41120
Merged
ephraimbuddy merged 2 commits intoapache:mainfrom Aug 13, 2024
Merged
Conversation
boring-cyborg
bot
added
area:CLI
area:db-migrations
ephraimbuddy
added
the
airflow3.0:breaking
ephraimbuddy
force-pushed
the
prune-migration-file
branch
from
3c720ce to
b67b0d4
Compare
ephraimbuddy
force-pushed
the
prune-migration-file
branch
3 times, most recently
from
6eed845 to
2762f60
Compare
ephraimbuddy
requested review from
XD-DENG,
ashb,
kaxil and
potiuk
as code owners
ephraimbuddy
requested review from
ashb,
jedcunningham,
kaxil and
potiuk
and removed request for
XD-DENG,
ashb,
kaxil and
potiuk
ephraimbuddy
force-pushed
the
prune-migration-file
branch
from
2762f60 to
d5f0a4f
Compare
ephraimbuddy
added
the
full tests needed
For a long time now, we have been able to create the metadata database from the ORM without going through the migration files. However, the migration files were not pruned because it would result in users being unable to roll back to a previous version. There's now an opportunity to prune this and start afresh. The migration files are getting more significant, and there are benefits to this pruning. Top in my mind is that the FAB migrations will no longer be in the airflow migration file, which would help in removing FAB from the Airflow core. This change also means we can no longer create a new database from the migration file. We can only do that through the ORM. I considered creating the 'current schema' in the migration file, which means having the database representation in the migration file and helping to create it from scratch. I dropped the idea because there would be elements of FAB in the migration files again. Due to this change, the db command option "--use-migration-files" was removed since this creates the database from the migration file.
ephraimbuddy
force-pushed
the
prune-migration-file
branch
from
d5f0a4f to
0120154
Compare
vincbeck
approved these changes
Aug 12, 2024
potiuk
approved these changes
Aug 12, 2024
Member
|
Overall LGMT, but we need to figure out what the min version we support upgrading from should be (2.10 vs some earlier 2.x). Ephraim is going to see where the FAB things are so in the migration files so we can figure out the best balance here. |
Member
|
Good point - my proposal is that migration from 2.x & should be another migration step (possibly combined with the main This way we could allow a direct migration from pre 2.10 versions as well. |
Contributor
Author
|
FAB-related migrations stopped at 2.6.0, so we are at liberty to still have the migration cut off way down, but I think we should cut 3.0.0 migration at 2.10 as in this PR and have a migration tool for anyone upgrading, as @potiuk suggested. |
Contributor
Author
|
Merging this, we can still extend it to lower versions if need be |
romsharon98
pushed a commit
to romsharon98/airflow
that referenced
this pull request
Aug 20, 2024
* Prune the migration files for Airflow 3 For a long time now, we have been able to create the metadata database from the ORM without going through the migration files. However, the migration files were not pruned because it would result in users being unable to roll back to a previous version. There's now an opportunity to prune this and start afresh. The migration files are getting more significant, and there are benefits to this pruning. Top in my mind is that the FAB migrations will no longer be in the airflow migration file, which would help in removing FAB from the Airflow core. This change also means we can no longer create a new database from the migration file. We can only do that through the ORM. I considered creating the 'current schema' in the migration file, which means having the database representation in the migration file and helping to create it from scratch. I dropped the idea because there would be elements of FAB in the migration files again. Due to this change, the db command option "--use-migration-files" was removed since this creates the database from the migration file. * fixup! Prune the migration files for Airflow 3
ephraimbuddy
added a commit
to astronomer/airflow
that referenced
this pull request
Feb 20, 2026
The `--use-migration-files` flag was removed in apache#41120 when we pruned the migration history for Airflow 3. At the time, we couldn't create a database from scratch using only migration files because the migration chain no longer started from an empty database. The oldest migration assumed an existing 2.6.2 schema. Now that we have a squashed migration (0000_2_6_2) with `down_revision = None` that creates the full baseline schema from scratch, we can re-introduce this flag. This enables a critical development workflow, which is: creating the database purely from migration files, then using `alembic revision --autogenerate` to detect schema drift between the ORM models and the migration-produced schema. Without this flag, `autogenerate` compares against an ORM-created database (via `create_all`), which masks any drift since both sides come from the same ORM definitions.
ephraimbuddy
added a commit
to astronomer/airflow
that referenced
this pull request
Feb 20, 2026
… ORM/migration files The `--use-migration-files` flag was removed in apache#41120 when we pruned the migration history for Airflow 3. At the time, we couldn't create a database from scratch using only migration files because the migration chain no longer started from an empty database. The oldest migration assumed an existing 2.6.2 schema. Now that we have a squashed migration (0000_2_6_2) with `down_revision = None` that creates the full baseline schema from scratch, we can re-introduce this flag. This enables a critical development workflow, which is: creating the database purely from migration files, then using `alembic revision --autogenerate` to detect schema drift between the ORM models and the migration-produced schema. Without this flag, `autogenerate` compares against an ORM-created database (via `create_all`), which masks any drift since both sides come from the same ORM definitions.
ephraimbuddy
added a commit
to astronomer/airflow
that referenced
this pull request
Feb 23, 2026
… ORM/migration files The `--use-migration-files` flag was removed in apache#41120 when we pruned the migration history for Airflow 3. At the time, we couldn't create a database from scratch using only migration files because the migration chain no longer started from an empty database. The oldest migration assumed an existing 2.6.2 schema. Now that we have a squashed migration (0000_2_6_2) with `down_revision = None` that creates the full baseline schema from scratch, we can re-introduce this flag. This enables a critical development workflow, which is: creating the database purely from migration files, then using `alembic revision --autogenerate` to detect schema drift between the ORM models and the migration-produced schema. Without this flag, `autogenerate` compares against an ORM-created database (via `create_all`), which masks any drift since both sides come from the same ORM definitions.
ephraimbuddy
added a commit
to astronomer/airflow
that referenced
this pull request
Feb 25, 2026
… ORM/migration files The `--use-migration-files` flag was removed in apache#41120 when we pruned the migration history for Airflow 3. At the time, we couldn't create a database from scratch using only migration files because the migration chain no longer started from an empty database. The oldest migration assumed an existing 2.6.2 schema. Now that we have a squashed migration (0000_2_6_2) with `down_revision = None` that creates the full baseline schema from scratch, we can re-introduce this flag. This enables a critical development workflow, which is: creating the database purely from migration files, then using `alembic revision --autogenerate` to detect schema drift between the ORM models and the migration-produced schema. Without this flag, `autogenerate` compares against an ORM-created database (via `create_all`), which masks any drift since both sides come from the same ORM definitions.
ephraimbuddy
added a commit
to astronomer/airflow
that referenced
this pull request
Feb 26, 2026
… ORM/migration files The `--use-migration-files` flag was removed in apache#41120 when we pruned the migration history for Airflow 3. At the time, we couldn't create a database from scratch using only migration files because the migration chain no longer started from an empty database. The oldest migration assumed an existing 2.6.2 schema. Now that we have a squashed migration (0000_2_6_2) with `down_revision = None` that creates the full baseline schema from scratch, we can re-introduce this flag. This enables a critical development workflow, which is: creating the database purely from migration files, then using `alembic revision --autogenerate` to detect schema drift between the ORM models and the migration-produced schema. Without this flag, `autogenerate` compares against an ORM-created database (via `create_all`), which masks any drift since both sides come from the same ORM definitions.
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
4 participants
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
For a long time now, we have been able to create the metadata database from the ORM without going through the migration files. However, the migration files were not pruned because it would result in users being unable to roll back to a previous version. There's now an opportunity to prune this and start afresh. The migration files are getting more significant, and there are benefits to this pruning. Top in my mind is that the FAB migrations will no longer be in the airflow migration file, which would help in removing FAB from the Airflow core.
This change also means we can no longer create a new database from the migration file. We can only do that through the ORM. I considered creating the 'current schema' in the migration file, which means having the database representation in the migration file and helping to create it from scratch. I dropped the idea because there would be elements of FAB in the migration files again.
Due to this change, the db command option "--use-migration-files" was removed since this creates the database from the migration file.