Rails: common approach for handling exceptions in restful actions on objects that have been destroyed?
It is very common in Rails for an objects_controller
controller to have RESTful edit
and destroy
actions like so:
def edit
@object = Object.find(params[:id])
end
def destroy
@object = Object.find(params[:id])
@object.destroy
redirect_to :back
end
With an associated view that provides edit and destroy links like so:
<%= link_to "Edit the Object", edit_object_path(object) %>
<%= link_to "Delete", object, :confirm => 'Are you sure?', :method =开发者_运维百科> :delete %>
And it is easy to blow this up. If I open two browser windows, A and B, destroy an object with the "Delete" link in browser A and then press the "Edit" link in browser B, the find()
in the edit
action throws an exception.
Updating to add Jakub's suggestion
There are several ways to deal with this:
- catch the exception and recover gracefully in the
edit
action - use
@object = find(:first, "conditions... etc.
and test the@object
in theedit
action - use a general 404
But seeing as this is such a common pattern, I would love to know how other folks deal with this situation.
You edit your 404 page in public/404.html
to be something reasonably friendly explaining that what the person is trying to access is not available anymore. That's the general solution. However your domain could allow for example soft-deleting and then you could offer to un-delete the record in the edit view. Checkout the Paranoid plugin for that (I'd implement it quite generally in a before_filter).
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