没有表格的Rails HABTM

Question

I have two models, Posts and Hashtags, in a HABTM relationship.

My post controller looks like this:

 def create
    @post = current_user.posts.new(params[:post])

    respond_to do |format|
      if @post.save
        format.html { redirect_to @post, :notice => 'Post was successfully created.' }
        format.json { render :json => @post, :status => :created, :location => @post }
      else
        format.html { render :action => "new" }
        format.json { render :json => @post.errors, :status => :unprocessable_entity }
      end
    end
  end

Now, when a user creates a new post, I want to do the following:

• check for hashtags, words starting with a '#'
• if the hashtag already exists, link the Post and the Hashtag
• if the hashtag does not exist, add it to Hashtags, and link the Post and the newly added Hashtag

I suppose I have to do this after I do the posts.new, but I am unsure how to proceed. Do I just edit the @post object? If so, what format should it be in for @post.save to pick up on the link?

Any suggestions would be greatly appreciated!

Answer 1

Ok, if you have your relationship setup properly you can run a regex on the post text to get all the hashtags out, then you could assign the hashtags with something like @post.hashtags = tags (tags being the hashtags you extracted from the text) and then save the model.

Another (less proper way I'd say), is to do the same but checking for the existence of the hashtag and creating them and saving them through the model, but good practice dictates that you do this through the relationship with the Post model.