Question

In rails when updating or creating, if i need to run another method this is what i have been doing for my apps.(located in my controller)

def create
  # Perform stuff
end

def update
  # Perform stuff
end

Something about this looks like it is really hacked out, there must be a more professional way of doing this than what i have now. Is there some way i need to set up my model in order to run tasks when a model is created or updated.

Answer 1

In Rails, your controllers handle your incoming web requests. So if a person clicks a link to create a new comment, they might hit a route like:

http://mysite.com/comments

Which is then routed to the CommentsController#create action. Now, if you have a lot of code that goes into creating a new comment, then yes you should move some of that into the Comment model. Otherwise, if it’s pretty straightforward, don’t worry about it.

Example of a straightforward scenario:

# POST /comments
def create
  @comment = Comment.new(:content => params[:comment_content])

  if @comment.save
    respond_with @comment
  else
    # error handling
  end
end

If you need to run a method after that comment is created, then put a callback in the Comment model:

class Comment < ActiveRecord::Base
  after_create :do_something

  def do_something
    # some code here
  end
end

---

If it’s more complex to create a comment (i.e. if there is a ton of code that you don’t want in the Controller), then move some code into the Comment model:

CommentsController

# POST /comments
def create
  @comment = Comment.create_comment!(params[:comment_content])

  if @comment.errors.any?
    # handle errors
  else
    respond_with @comment
  end
end

Comment Model

class << self
  def create_comment!(comment_content)
    comment = Comment.new(:content => comment_content)

    # lots of complex comment creation code goes here

    return comment
  end
end

This allows you to keep you controller code simple while moving more verbose code into your Model.