Rails: Running a script based on values in the database

Question

Right now, I have some tooltip JavaScript that I'd like to run on every page of my app, but only if the current user's model has User.advanced_tooltips set to true in my database.

What is the best way conceptually to get this JavaScript to trigger conditionally based on a value in a database? I'm having some real trouble getting JavaScript and Rails to communicate.

You could use jQuery and Ajax. Check the answer from here. http://stackoverflow.com/questions/578095/how-to-get-data-with-javascript-from-another-server — Hachi, Nov 04 '12 at 00:31

score 1 · Answer 1 · answered Nov 04 '12 at 00:53

1

You could do something like this, assuming you are using jquery:

<script type='text/javascript'>
$(document).ready(function() {
   var advtt = '<%= @user.advanced_tooltips ? "yes" : "no" %>';
   if ( advtt == 'yes')
     # ?? add css, or whatever
});
</script>

This assumes @user is set in the controller before rendering the view that contains the above Javascript.

answered Nov 04 '12 at 00:53

RadBrad

7,234
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17

That's how I normally track my user, in a before_filter that sets @user before each controller action. However, this project uses the session variable to store the current user's id, and -- since I jumped on this project's team mid-completion -- major refactoring isn't really an option. – Adam Templeton Nov 05 '12 at 18:32
I don't see how that would require a major refactoring. All you need to do is replace @user.advanced_tooltips with User.find(session[:user_id]).advanced_tooltips, or whatever it is. – RadBrad Nov 05 '12 at 18:39

score 1 · Answer 2 · answered Nov 04 '12 at 11:19

1

A clean and simple solution is to wrap javascript functions in rails logic:

<script type='text/javascript'>

  var setupTooltips = function() {
    // do something here
  }

  $(document).ready(function() {

    <% if current_user.advanced_tooltips %>
      setupTooltips();
    <% end %>

  });

</script>

answered Nov 04 '12 at 11:19

aguynamedloren

2,273
18
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Unfortunately, this is what my initial attempt at a solution looked like. I tried both embedded the code in my layout (which worked until I rendered certain views in pop-up modals sans layout) and in a js.erb file (where it was apparently unable to access the session variable, which is how I'm storing the user) – Adam Templeton Nov 05 '12 at 18:30

score 0 · Accepted Answer · answered Nov 05 '12 at 18:36

Here's the solution I ended up using (given the very weird constraints imposed by this project):

First, I set up a controller route that finds the current User and then renders its advanced_tooltip value as text.

Then, in my application.js, I made an AJAX call using $.get to that route, then checked whether the result == "true" to determine whether or not a user had advanced tooltips enabled.

It's a messy solution (and those listed above are actually better), but since I had some very rigid restrictions due to me jumping onto someone else's project's mid-completion, it's what I had to do.

Still gave both comment up-votes, as they're valid and would totally work under normal circumstances.

Rails: Running a script based on values in the database

3 Answers3