Transparently integrate Flyway 6.0's support JavaMigration instances created by DI frameworks

[axelfontaine]

Starting with Flyway 6.0 (due out in Q1 2019), Spring users can use this to automatically use all JavaMigration Spring beans with Flyway:

import org.flywaydb.core.Flyway;
import org.flywaydb.core.api.migration.JavaMigration;
import org.springframework.context.ApplicationContext;

...
ApplicationContext applicationContext = ...; // obtain a reference to Spring's ApplicationContext.

Flyway flyway = Flyway.configure()
    .dataSource(url, user, password)
    // Add all Spring-instantiated JavaMigration beans
    .javaMigrations(applicationContext.getBeansOfType(JavaMigration.class).values().toArray(new JavaMigration[0]))
    .load();
flyway.migrate();

Spring Boot is most certainly able to make this fully transparent for its users.

References:

• API: Make it possible to use pre-instantiated Java-based migrations flyway/flyway#1062 (comment)
• https://twitter.com/snicoll/status/1072755676923998208

[SammyVimes]

Is there still no assignee? If so, I'd like to work on that task

[wilkinsona]

@SammyVimes Thanks for the offer, but Flyway 6 has not yet been released so nothing can be done here at the moment.

[SammyVimes]

@wilkinsona Yes, but it's possible to use Java migrations in Flyway Beta, so I thought I can add support for it and merge when the release comes out :)

[wilkinsona]

Cool. If you'd like to prepare something against the beta, ready to be updated to the GA when it's released and then merged, that'd be much appreciated.

[SammyVimes]

Done! Waiting for GA (looks like it will happen in the beginning of april).

Also, there has been slight API changes in Flyway6, so I had to fix the compatibility.

[wilkinsona]

Great! Thanks very much. Would you mind splitting the changes into two separate commits? One that does the upgrade and makes the necessary changes for breaking API changes, and one that adds support for Java migrations?

[SammyVimes]

Ofcourse!

[SammyVimes]

Flyway6

AutoConfiguration

To clarify: I've put them to different branches, so I can rebase and squash Flyway6 branch when it will be released and then autoconfiguration branch could be rebased onto it.

[wilkinsona]

This looks great. Thanks very much @SammyVimes. We'll look forward to Flyway 6's release so that we can get those changes merged.

[kedar-joshi]

Flyway 6.0 is now GA.

[SammyVimes]

Yay, thanks for the notice, I'll have merge request ready today!

[SammyVimes]

Whoops, looks like flyway 6.0.0 is broken! Tests with H2 database usage fail and the commit log of flyway repo contains this commit (so H2 just doesn't work right now)

[wilkinsona]

Looks like we'll have to wait for 6.0.1 which is currently scheduled for 27/8: https://github.com/flyway/flyway/milestone/37.

[kedar-joshi]

Flyway 6.0.1 released https://github.com/flyway/flyway/releases/tag/flyway-6.0.1.

[SammyVimes]

Good, I will update my code later this day

[wilkinsona]

Closing in favour of #17993.