Question

I have a form to create posts. This form also has tags on the post and it is owned by a user. The form is using a virtual attribute :tag_ids.

I would like to do something like this, where you find_or_create_by_name_and_user_id and then just pass the current_user.id.

def tag_ids=(tags_string)
    self.taggings.destroy_all
    tag_names = tags_string.split(",").collect{|s| s.strip.downcase}.uniq
    tag_names.each do |tag_name|
      tag = Tag.find_or_create_by_name_and_user_id(tag_name, current_user.id)
      tagging = self.taggings.new
      tagging.tag_id = tag.id
    end
end

From what I read this isn’t how it should work. The current user should be called in the PostsContoller create method.

def create
  @post = Post.new(params[:post])
  @post.user = current_user
  respond_to do |format|
     if params[:commit]
     @post.save

…
end

This is where I’m stuck. If the params are passing all of the attributes, how can I inject the current_user id into tag model which has a :name and :user_id attribute?

I also read that this should work because of my associations.

User – has_many posts; has_many tags

Post – belongs_to user; has_many taggings; has_many tags through taggings

Tag – has many taggings; has_many posts through taggings; belongs_to user

Tagging – belongs_to post; belongs_to tag

Answer 1

You can’t get current_user in model ,you have to pass explicitly,there are may be couple of hack to do this,But simple way is,user is already stored in post so self.user.id is useful
If above method is in post model,post user is tagging user.

Tag.find_or_create_by_name_and_user_id(tag_name, self.user.id)