Daily Refactor #69: Inline Temp in SourceNews#migrate

I wanted to start refactoring my Redmine merge plugin now. I’m getting it ready for a release so doing a few refactorings now will help me make sure it’s working properly.

The Refactoring

Using inline temp I was able to clean up how the SourceNews#migrate converts data from one database to the other database.

Before

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class SourceNews  'SourceUser', :foreign_key => 'author_id'
 
  def self.migrate
    all.each do |source_news|
      n = News.new
      n.attributes = source_news.attributes
      n.project = Project.find(RedmineMerge::Mapper.get_new_project_id(source_news.project_id))
      n.author = User.find_by_login(source_news.author.login)
      n.save!
    end
  end
end

After

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class SourceNews  'SourceUser', :foreign_key => 'author_id'
 
  def self.migrate
    all.each do |source_news|
      News.create!(source_news.attributes) do |n|
        n.project = Project.find(RedmineMerge::Mapper.get_new_project_id(source_news.project_id))
        n.author = User.find_by_login(source_news.author.login)
      end
    end
  end
end

Review

Since SourceNews#migrate was a pretty simple method, this refactoring is easy to understand. By using the block method of ActiveRecord#create! I don’t have to worry about calling #save! at the end. It’s also a nice and simple way to keep all of the News construction in places (inside the block).

Reference commit