Question

Is there a way to set up a Rails model to have default associations to existing resources, i.e. I create a new blog post and it automatically gets assigned author with id 10.

Answer 1

You could do something like this in your BlogPost model, this would assign user 10 with every blog post that’s created.

after_create do |blog_post|
  blog_post.user = User.find(10)
  blog_post.tags = Tag.all  # Or whatever
end

Edit:

To have this happen when you call new use the after_initialize callback instead:

after_initialize do |blog_post|
  blog_post.user = User.find(10)
  blog_post.tags = Tag.all  # Or whatever
end