Question

To start out, I know what I am trying to do is not typical to Rails. I open to suggestions to better alternatives. I am novice with rails so suggestions are welcome 🙂

Basically, I have a notifications bar that has 5 notifications. After a user clicks and sees the notifications I want to set the a column in the database called seen to true.

Here is my Jquery function:

<script type="text/javascript">
            $(document).ready(function(){
              $("button").click(function(){
                    $("div#count").html("<%= escape_javascript(render('shared/notification_count')) %>");
              });
            });
</script>

And here is the code I am trying to execute only after the click(located in _notification_count.html.erb)

<% notification_ids =   current_user.notifications.map(&:id).join(', ')%>
<% sql = "UPDATE notifications SET SEEN = true where id IN(#{notification_ids})" %>
<% User.connection.select_all(sql) %>

However, it appears that this code is getting executed automatically when the page loads and not after the click. What is my problem?

Answer 1

Firstly, you cannot simply attach a render to your button to make changes to your database (whether it’s a read or a write). You must make an AJAX call back to your controller using something like

$.ajax({
    url: "/path/to/your/method",
    type: "GET",
    dataType: "script"
});

And in your controller you will handle what you need to do, and then render your js file with a

respond_to do |format|
    format.js {render 'shared/notification_count'}
end

This is because when a user clicks on your button, the code will be executed on the clients side, but if you never make a request back to the server, then you will not be able to see the updated version of your database. I suggest you reading more on this, that helped me a lot.