knu / git-merge-structure-sql

git merge driver for db/structure.sql of Rails projects

git-merge-structure-sql

This is a merge driver for Git that resolves typical merge conflicts in a db/structure.sql file of Rails.

When your project is configured with config.active_record.schema_format = :sql, the database schema is kept in db/structure.sql instead of db/schema.rb in the native dump format of the underlying database engine, which is not suitable for the default merge driver of Git to deal with. As a result, when you try to merge two branches you always have to resolve trivial conflicts manually if new schema migrations take place in both branches. This custom driver takes away such a pain.

Currently only PostgreSQL, MySQL and SQLite3 dump formats are supported.

Installation

Run this:

$ gem install git-merge-structure-sql

And enable it yourself in your Git configuration, or let it do that for you by this command:

$ git-merge-structure-sql --install

This adds necessary settings to your ~/.gitconfig or $XDG_CONFIG_HOME/git/config and the default gitattributes(5) file to enable the merge driver for structure.sql files.

If you want to enable this driver only in the current git directory, run this:

$ git-merge-structure-sql --install=local

Usage

Once enabled, Git should call this driver as necessary when it needs to merge changes made in structure.sql.

History

See CHANGELOG.md for the version history.

Author

Copyright (c) 2018-2021 Akinori MUSHA.

Licensed under the 2-clause BSD license. See LICENSE.txt for details.

Visit the GitHub Repository for the latest information.

git-merge-structure-sql's Issues

git-merge-structure-sql: No such file or directory @ rb_sysopen - /Users/X/.gitattributes

Thanks for the work on this, looks great!

When I was running git-merge-structure-sql --install, I got the error:

git-merge-structure-sql: No such file or directory @ rb_sysopen - /Users/X/.gitattributes

I'm not entirely sure how .gitattributes normally gets initialized, but I was wondering how you generally approach this. We want to have this initialized easily for our engineering team, so not doing this manually would be ideal. Additionally, we are running this directly from a rails codebase and have a .gitattributes file checked in, but based on the locations searches, it won't use it. So, we see 2 options:

1. Find a way to initialize .gitattributes, not sure if it makes sense to be in this library
2. Support looking for .gitattributes in the current directory we are installing git-merge-structure-sql in

Maybe we are approaching this wrong and there's another approach that would work, suggestions welcome!

/cc @alexanderjeurissen

Feature Request: respect .gitattributes

I typically recommend teams to use .gitattributes for recommended tooling that most team members are encouraged to use. ie the structure merge-driver; rails credentials for filter/smudge; etc

For repositories that already have the merge-structure-sql driver configured in .gitattributes, it is redundant (and potentially confusing to debug) when the local installation still writes to .git/info/attributes.

It would be nice if git-merge-structure-sql --install=local would detect that merge-structure-sql is already registered in .gitattributes (perhaps even checking db/.gitattributes? does git provide a plumbing command for checking this?) and to skip writing .git/info/attributes.

Thanks for the merge-driver; Works great!