Sort migration ids before writing to summary file

[kshepard]

I encountered a problem when performing the following steps:

• Use the example project, perform an mg init followed by a mg migrate
• Delete the database file
• Run another mg init followed by a migrate
• The migrations failed to run, because the migrations summary file had the migrations listed in an incorrect order (M3, M2, M1) -- it would try to run M3 first and would fail.

This commit ensures that the migrations in the summary file are properly ordered and fixes the above issue.

[lastland]

Hi @kshepard,

Thanks for reporting this and submitting a pull request! However, there are a few things I would like to clarify:

• You are not supposed to run mg init after mg migrate. The command should only be run the first time you start the migration or after a mg reset command.
• Deleting the database file manually is NOT recommended for restarting the migrations. The best way to do it is via the mg reset command: it will reset the database as well as other related files (like the summary file and the generated source code).

Maybe I should try to make this explanation more visible somewhere.

[lastland]

The identifier sortedIds is not used in anywhere but the next line. Maybe it's a good idea to chain it in the next line (like ids.sortWith(...).map(...))? What do you think?

[kshepard]

Yeah, that sounds good to me, I'll update the PR.

[kshepard]

Hi @lastland, thanks for taking a look at the PR!
The reason I was deleting the database file was to simulate a deployment scenario. I wanted to see what it would be like to develop the migrations locally, and then at a later time, change my database configuration and migrate a different, remote database. The database deletion was a simple way for me to test this out without needing to set up a completely separate database, but the results should be the same.

[lastland]

@kshepard Yeah that makes good sense. Thanks again for the PR!

[kshepard]

No problem, thanks for building this project!
Also, curious about your release cycle: approximately when do you next expect to publish a 0.2.2 release?

[lastland]

There has been quite a few changes so I plan to publish a 0.2.2 release soon -- hopefully tomorrow. Would that be OK for you?

[kshepard]

Sounds wonderful, thank you!

[lastland]

0.2.2 is released, though it may take a few hours before the release is synced to mvn repo center.