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Ruby

Posted by Dave Faliskie
Dave Faliskie
17,793 Points

sorting by forum topics

Im using ruby to make a forum. I have it set up so that each post has a topic. I was wondering how you can sort by the topic using buttons. Basically I want it to be like the treehouse forum where there is a list of topics and then a user can click a button and they will only see posts from that topic?

Im using Ruby so would this be the show file? my posts are called Discussions so I tried sorting the show with:

Discussion.where("topic = ?", @topic)

this seems to work but how do I set the variable @topic with different buttons.

Any help would be awesome.

1 Answer

Geoff Parsons
Geoff Parsons
11,679 Points

The simplest way would probably just be to pass the topic's ID in via a link_to:

  <% for topic in @topics do %>
    <%= link_to topic.name, discussions_path(topic_id: topic.id), class: "button" %>
  <% end %>

And then in your controller action you'd want to find by topic_id (assuming Discussion belongs_to topic):

  @discussions = Discussion.where(topic_id: params[:topic_id])
Dave Faliskie
Dave Faliskie
17,793 Points

I have it set up so that the topic is a column in the discussions table. Should I make the topics a table of their own?

Geoff Parsons
Geoff Parsons
11,679 Points

Ah, i apologize for the misunderstanding.

There's arguments for and against normalizing to that level. You can always extract it into its own table later via a migration.

If topic is just a string then you can pass it along in much the same way as i mentioned above:

  <%= link_to topic.name, discussions_path(topic: topic), class: "button" %>

  @discussions = Discussion.where(topic: params[:topic])

You may also want to look into setting up a custom route with a bound parameter. As it stands this will send topic via a GET parameter in the URL (e.g. /discussions?topic=ruby). A custom route may look nicer and make it less obvious how things work on the inside (e.g. /discussions/ruby).

Dave Faliskie
Dave Faliskie
17,793 Points

Thank you, Works perfectly!