restore best-effort behavior of afterColumn

Environment

Liquibase Version: 4.13.0

Liquibase Integration & Version: gradle, spring boot

Liquibase Extension(s) & Version:

Database Vendor & Version: mysql, postgresql

Operating System Type & Version:

Infrastructure Type/Provider:

Description

https://github.com/spinnaker/orca (migrations are here) uses afterColumn in some of its migrations, and tests those migrations using both mysql and postgresql. Before version 4.13.0, and specifically https://github.com/liquibase/liquibase/pull/2943, afterColumn worked with mysql, and did nothing with postgresql. With 4.13.0, afterColumn still works with mysql, but throws a validation error with postgresql. For example:

PgTopApplicationExecutionCleanupPollingNotificationAgentSpec > initializationError FAILED
    com.netflix.spinnaker.kork.sql.test.SqlTestUtil$DatabaseInitializationFailed: liquibase.exception.ValidationFailedException: Validation Failed:
         4 changes have validation failures
              addAfterColumn is not allowed on postgresql, db/changelog/20180510-add-legacy-id-fields.yml::add-legacy-id-fields::cthielen
              addAfterColumn is not allowed on postgresql, db/changelog/20180510-add-legacy-id-fields.yml::add-legacy-id-fields::cthielen
              addAfterColumn is not allowed on postgresql, db/changelog/20180510-add-legacy-id-fields.yml::add-legacy-id-fields::cthielen
              addAfterColumn is not allowed on postgresql, db/changelog/20180510-add-legacy-id-fields.yml::add-legacy-id-fields::cthielen
        at com.netflix.spinnaker.kork.sql.test.SqlTestUtil.initDatabase(SqlTestUtil.java:248)
        at com.netflix.spinnaker.kork.sql.test.SqlTestUtil.initTcPostgresDatabase(SqlTestUtil.java:97)
        at com.netflix.spinnaker.orca.sql.cleanup.PgTopApplicationExecutionCleanupPollingNotificationAgentSpec.getDatabase(TopApplicationExecutionCleanupPollingNotificationAgentSpec.groovy:161)

        Caused by:
        liquibase.exception.ValidationFailedException: Validation Failed:
             4 changes have validation failures
                  addAfterColumn is not allowed on postgresql, db/changelog/20180510-add-legacy-id-fields.yml::add-legacy-id-fields::cthielen
                  addAfterColumn is not allowed on postgresql, db/changelog/20180510-add-legacy-id-fields.yml::add-legacy-id-fields::cthielen
                  addAfterColumn is not allowed on postgresql, db/changelog/20180510-add-legacy-id-fields.yml::add-legacy-id-fields::cthielen
                  addAfterColumn is not allowed on postgresql, db/changelog/20180510-add-legacy-id-fields.yml::add-legacy-id-fields::cthielen
            at liquibase.changelog.DatabaseChangeLog.validate(DatabaseChangeLog.java:307)
            at liquibase.Liquibase.lambda$update$1(Liquibase.java:228)
            at liquibase.Scope.lambda$child$0(Scope.java:180)
            at liquibase.Scope.child(Scope.java:189)
            at liquibase.Scope.child(Scope.java:179)
            at liquibase.Scope.child(Scope.java:158)
            at liquibase.Liquibase.runInScope(Liquibase.java:2400)
            at liquibase.Liquibase.update(Liquibase.java:208)
            at liquibase.Liquibase.update(Liquibase.java:194)
            at liquibase.Liquibase.update(Liquibase.java:190)
            at liquibase.Liquibase.update(Liquibase.java:182)
            at com.netflix.spinnaker.kork.sql.test.SqlTestUtil.initDatabase(SqlTestUtil.java:246)
            ... 2 more

One use of afterColumn is:

    - addColumn:
        tableName: orchestration_stages
        columns:
        - column:
            name: legacy_id
            type: varchar(500)
            afterColumn: id

Expected/Desired Behavior

https://github.com/liquibase/liquibase/pull/2943 notes that this is the new behavior. I’d love a way to go back to the old behavior, where addColumn works where supported, and is ignored where it’s not. There are some migrations where adding e.g.:

modifySql:
  dbms: "mysql"
  append:
    value: " after id"

works, but many where it doesn’t.

[kataggart]

thanks @jfisbein - also saw you comment over on #3094. Same issue, different command. Stay tuned.

[dbyron-sf]

Turns out that https://github.com/liquibase/liquibase/issues/3094#issuecomment-1194426594 is actually the heart of the matter:

I’m mainly interested in my changelogs not breaking, and your change breaks them both ways… Leaving the postition=“x” in breaks things, removing the attribute also breaks things, since the signature of the changeset changes.

And yes, there is also the thing about different platforms, which is one of the main selling points for Liquibase 😃

So even if it’s possible to do things with custom sql, the changeset checksums fail.

I think what I’m really asking for is to change this from an enhancement to a bug.