I want to log the current backtrace (stacktrace) in a Rails 3 app without an exception occurring. Any idea how?
Why do I want this? I'm trying to trace the calls that are made when Rails looks for a template so that I can choose a part of the process to override (because I want to change the view path for a particular subclassed controller of mine).
I'd like to call it from the file: gems\actionpack-3.2.3\lib\action_dispatch\middleware\templates\rescues\missing_template.erb. I know that's not best practice, but I know it's downstream of the stack from where the search for templates occurs.
3 Answers
You can use Kernel#caller:
# /tmp/caller.rb def foo puts caller # Kernel#caller returns an array of strings end def bar foo end def baz bar end baz Output:
caller.rb:8:in `bar' caller.rb:12:in `baz' caller.rb:15:in `<main>' Try using
Thread.current.backtrace I use this to show a custom error page when exception are raised.
rescue_from Exception do |exception| logger.error exception.class logger.error exception.message logger.error exception.backtrace.join "\n" @exception = exception # ExceptionNotifier::Notifier.exception_notification env, @exception respond_to do |format| if [AbstractController::ActionNotFound, ActiveRecord::RecordNotFound, ActionController::RoutingError, ActionController::UnknownAction].include?(exception.class) format.html { render :template => "errors/404", :status => 404 } format.js { render :nothing => true, :status => 404 } format.xml { render :nothing => true, :status => 404 } elsif exception.class == CanCan::AccessDenied format.html { render :template => "errors/401", :status => 401 #, :layout => 'application' } # format.js { render :json => { :errors => [exception.message] }, :status => 401 } # format.js { render :js => 'alert("Hello 401")' } format.js { render :template => 'errors/401.js.erb' } else ExceptionNotifier::Notifier.exception_notification(env, exception).deliver format.html { render :template => "errors/500", :status => 500 } #, :layout => 'im2/application' } # format.js { render :nothing => true, :status => 500 } format.js { render :template => 'errors/500.js.erb' } end end end 
