Rails Newbie: Recommendations for error handling in controller
Sorry if the question is obvious, I am only starting to work with Rails.
I have a following code in se开发者_如何学编程veral controller methods now:respond_to do |format|
if @project.save
format.html { redirect_to(edit_project_url(@project), :notice => '#{user.name} added to #{role}.') }
format.js
else
format.html { render :action => "edit" }
format.js #...
end
end
So the question is, what is the best way to do the same thing for errors in all methods?
Is it recommended that I usesave!
and handle it in rescue_action
?
Or should I do my own respond
method and pass save
in a block?
It's often more convenient to use the exception-raising variant of save and rescue that later in the block than to branch like that. The advantage to exceptions is they'll bust out of transactions.
def create
@project.save!
respond_to do |format|
format.html { redirect_to(edit_project_url(@project), :notice => '#{user.name} added to #{role}.') }
format.js
end
rescue ActiveRecord::RecordInvalid
respond_to do |format|
format.html { render :action => "edit" }
format.js #...
end
end
You'll find that it gets really tricky to wrangle your way out of a pile of nested if
statements when trying to save more than one object at a time, but a simple rescue
for exceptions will handle it neatly.
def create
Project.transaction do
@project.save!
@something_else.save!
@other_stuff.save!
end
# ...
rescue ActiveRecord::RecordInvalid
# ...
end
If any one of those saves blows up you'll get an exception. To ensure that all of them are displaying validation errors you might have to call .valid?
on each to prime them or you will have those after the failure left untested.
It's not a bad thing to use the if @object.save
pattern. However, if you are doing exactly the same for all your actions on your controller, you can define a rescue_from
action.
Something like
class MyController < ActionController::Base
rescue_from ActiveRecord::RecordInvalid do
render :action => edit
end
end
精彩评论