# Relationships... not the personal kind!

**URL:** <https://www.ruby-forum.com/t/relationships-not-the-personal-kind/52887>\
**Category:** Rails\
**Created:** [January 19, 2006, 10:53pm UTC](https://www.ruby-forum.com/t/relationships-not-the-personal-kind/52887 "2006-01-19T22:53:31Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![Ted\_Oleander](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/t/f19dbf/32.png) [@Ted\_Oleander](https://www.ruby-forum.com/u/Ted_Oleander)\
**Post date:** [January 19, 2006, 10:53pm UTC](https://www.ruby-forum.com/t/relationships-not-the-personal-kind/52887/1 "2006-01-19T22:53:31Z")

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Hello all,

I’m very new to Rails and I love it so far. However, there are some  
things that aren’t so clear to me.

Let’s say a blog post can have many comments, and a comment can only  
belong to one post. A user can have many posts and many comments as  
well. (this part makes perfect sense):

class Comment \< ActiveRecord::Base  
belongs\_to :posting  
belongs\_to :user  
end

class Posting \< ActiveRecord::Base  
has\_many :comments  
belongs\_to :user  
end

class User \< ActiveRecord::Base  
has\_many :comments  
has\_many :postings  
end

In the comment\_controller, how would I actually go about saving the  
comment with the appropriate foreign keys of the posting and user. In  
the comments table I have the appropriate columns (posting\_id,  
user\_id).

Here’s what I have in the comment\_controller for creating a new comment:

def new  
@comment = Comment.new  
end

def create  
@comment = Comment.new(params[:comment])  
@comment.users\_ip = request.remote\_ip  
@comment.users = session[:user] \<— Doesn’t work… stumped  
@comment.posting = @posting \<---- Where I’m stumped again  
if @comment.save  
flash[:notice] = ‘Comment was successfully created.’  
redirect\_to :action =\> ‘list’  
else  
render :action =\> ‘new’  
end  
end

Am I close at all? Is using the session[:user] the best way to get the  
logged in user to associate the comment and user?

Thank you in advanced,  
Ted

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**Author:** ![Ted\_Oleander](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/t/f19dbf/32.png) [@Ted\_Oleander](https://www.ruby-forum.com/u/Ted_Oleander)\
**Post date:** [January 20, 2006, 5:38pm UTC](https://www.ruby-forum.com/t/relationships-not-the-personal-kind/52887/2 "2006-01-20T17:38:17Z")

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On Jan 19, 2006, at 2:15 PM, Ted Oleander wrote:

> belongs\_to :posting  
> has\_many :postings  
> def new  
> redirect\_to :action =\> ‘list’  
> else  
> render :action =\> ‘new’  
> end  
> end

Looks pretty close to me!

One thing to keep in mind when you make use of associations is that  
whatever the symbol you use to define the association, that symbol is  
now the “key” in to how Rails creates all of the automagical methods.

For example, you’ve defined Comment belongs\_to :user. Note that  
you’ve used a singular ‘user’, so the automagical methods created by  
rails will be singular in this case. Thus, your “Doesn’t work…  
stumped” line up above should read:

@comment.user = session[:user]

Second, I’m not sure where the @posting variable is coming from. Do  
you have a before\_filter that sets it up somewhere? Otherwise,  
@posting is going to be nil, and that will be the equivalent of  
_un_setting the association. If you have the id of the posting in  
the params, for example, you could just do this:

@comment.posting\_id = params[:id]

Or if you have the actual object, e.g. @posting = Posting.find(params  
[:id]) then the code you’ve written above will work fine.

> Am I close at all? Is using the session[:user] the best way to get the  
> logged in user to associate the comment and user?
> 
> Thank you in advanced,  
> Ted

You’re welcome, and good luck!

Duane J.  
(canadaduane)  
[http://blog.inquirylabs.com/](http://blog.inquirylabs.com/)

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<div class="post-metadata">

**Author:** ![Ted\_Oleander](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/t/f19dbf/32.png) [@Ted\_Oleander](https://www.ruby-forum.com/u/Ted_Oleander)\
**Post date:** [January 20, 2006, 8:45pm UTC](https://www.ruby-forum.com/t/relationships-not-the-personal-kind/52887/3 "2006-01-20T20:45:50Z")

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Thanks Duane. That cleared some issues up for me.

For some reason though this doesn’t work:  
@comment.user = session[:user]

…but this does:  
@comment.user\_id = session[:user]

Even though it works the above way, is it the right way?

The comment issue: When the posting id comes into the “new” action for  
the comment, it comes in like this from  
[http://localhost:3000/listings/](http://localhost:3000/listings/)  
[http://localhost:3000/comments/new/1](http://localhost:3000/comments/new/1) ← For post number 1  
[http://localhost:3000/comments/new/2](http://localhost:3000/comments/new/2) ← For post number 2  
etc…

I’ve tried adding the following in the ‘new’ action in the Comments  
controller:

posting\_id = Comment.new(params[:id]) # Always is saved as ‘1’  
@comment.posting\_id = posting\_id

I’ve changed the params[:id] to params[:posting\_id] but I’ve had no  
luck with that.

Thanks,  
Ted

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<div class="post-metadata">

**Author:** ![Ted\_Oleander](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/t/f19dbf/32.png) [@Ted\_Oleander](https://www.ruby-forum.com/u/Ted_Oleander)\
**Post date:** [January 20, 2006, 8:54pm UTC](https://www.ruby-forum.com/t/relationships-not-the-personal-kind/52887/4 "2006-01-20T20:54:54Z")

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Ted,

I had a similar issue recently. I have no idea if this is ‘the best’  
way to accomplish it, but it works.

In your ‘new’ action you could grab the id parameter passed in and  
place it in the session:

session[:posting\_id] = params[:id]

Then in your create action you could do access it like this:

@comment.posting\_id = session[:posting\_id]

Be sure to erase the session variable after saving.

There has to be a better way though. All these session variables could  
really slow the system down over time.

Hope that helps a little!  
-Dave

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<div class="post-metadata">

**Author:** ![Ted\_Oleander](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/t/f19dbf/32.png) [@Ted\_Oleander](https://www.ruby-forum.com/u/Ted_Oleander)\
**Post date:** [January 20, 2006, 11:44pm UTC](https://www.ruby-forum.com/t/relationships-not-the-personal-kind/52887/5 "2006-01-20T23:44:25Z")

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On Jan 20, 2006, at 12:05 PM, Ted Oleander wrote:

> Thanks Duane. That cleared some issues up for me.
> 
> For some reason though this doesn’t work:  
> @comment.user = session[:user]
> 
> …but this does:  
> @comment.user\_id = session[:user]

Are you storing the ID of the user in the session? Both ways are  
valid, you just have to be sure of which convention you’re using 🙂  
It’s good (in general) to add an \_id to the end if it’s an id. E.g.:

@comment.user\_id = session[:user\_id]

Makes it more consistent, but this requires that you set the  
session’s user\_id somewhere. Where are you setting the session  
[:user]? I would switch it to session[:user\_id] = if that  
is indeed what is going on, just for readability’s sake. However, if  
it works, it works.

> controller:
> 
> posting\_id = Comment.new(params[:id]) # Always is saved as ‘1’  
> @comment.posting\_id = posting\_id
> 
> I’ve changed the params[:id] to params[:posting\_id] but I’ve had no  
> luck with that.

That code looks somewhat circuitous 🙂

Try this:

@comment = Comment.new(params[:comment])  
@comment.posting\_id = params[:id]  
if @comment.save  
# send success message etc.  
end

This assumes that you’re using the FormHelper methods in a standard  
way, e.g. in your view:

\<%= start\_form\_tag :action =\> ‘new’, :id =\> params[:id] %\>  
Your N.: \<%= text\_field ‘comment’, ‘name’ %\>  
  
Comment: \<%= text\_field ‘comment’, ‘body’ %\>  
… etc …  
\<%= end\_form\_tag %\>

Note that :id =\> params[:id] is necessary for postback forms (like  
yours) so that the Posting id is retained when the comment is submitted.

Duane J.  
(canadaduane)  
[http://blog.inquirylabs.com/](http://blog.inquirylabs.com/)