Raise Rails Error
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here for a quick overview of the site Help Center Detailed answers to any questions you might have Meta Discuss the workings and policies of this site About Us Learn more about Stack Overflow the company Business Learn more about hiring developers rails raise custom exception or posting ads with us Stack Overflow Questions Jobs Documentation Tags Users Badges Ask Question x rails exceptions Dismiss Join the Stack Overflow Community Stack Overflow is a community of 6.2 million programmers, just like you, helping each other. Join them; it rails raise exception in model only takes a minute: Sign up How do I raise an exception in Rails so it behaves like other Rails exceptions? up vote 51 down vote favorite 11 I would like to raise an exception so that it does the rails exception types same thing a normal Rails exception does. Specially, show the exception and stack trace in development mode and show "We're sorry, but something went wrong" page in production mode. I tried the following: raise "safety_care group missing!" if group.nil? But it simply writes "ERROR signing up, group missing!" to the development.log file ruby-on-rails exception exception-handling share|improve this question asked Dec 16 '09 at 22:49 Chirag Patel 2,24762433 2 the error message you posted does not seem to come from this
Rails Standard Error
exception (it's a different message) is this really what you're seeing? –levinalex Dec 17 '09 at 0:31 add a comment| 2 Answers 2 active oldest votes up vote 84 down vote accepted You don't have to do anything special, it should just be working. When I have a fresh rails app with this controller: class FooController < ApplicationController def index raise "error" end end and go to http://127.0.0.1:3000/foo/ I am seeing the exception with a stack trace. You might not see the whole stacktrace in the console log because Rails (since 2.3) filters lines from the stack trace that come from the framework itself. See config/initializers/backtrace_silencers.rb in your Rails project share|improve this answer edited Dec 17 '09 at 0:30 answered Dec 17 '09 at 0:11 levinalex 3,8902544 2 Excellent, concise answer. –rcd Jan 5 '14 at 22:13 The skitch link (seeing the exception with a stack trace) isn't working anymore –Asaf Jun 14 at 12:47 @levinalex will this be safe in production mode to show the stacktrace? –BKSpurgeon Aug 24 at 4:18 @levinalex - thank you alex. is there any way of adding a custom string to the error message ? –BKSpurgeon Aug 24 at 4:26 add a comment| up vote 38 down vote You can do it like this: class UsersController < ApplicationController ## Exception Handling class NotActivated < StandardError end rescue_from NotActivated, :with => :not_activated def not_activated(exception) flash[:notice] = "This
and rescuing custom errors in a Rails application. It's often useful to map custom Ruby errors to HTTP response status codes and have Rails render the appropriate HTML error pages.
Raise Error Ruby
For example, you might have a controller that is acting as a simple proxy rails raise internal server error to a third party service such as Twitter or Facebook, and you need any of the HTTP errors encountered when calling those ruby raise custom exception sites to be handled natively by your app. Another use case would be in a Service-oriented architecture (SOA), where you want any errors in your back end services propagated to your front end web application. http://stackoverflow.com/questions/1918373/how-do-i-raise-an-exception-in-rails-so-it-behaves-like-other-rails-exceptions In this post we'll demonstrate rescuing status errors in an imaginary proxy controller using the awesome Faraday gem. For the sake of brevity we've omitted the inclusion of tests though in the wild we'd build such a feature using TDD and our favourite test weapon, RSpec. Not Found To start, let's handle basic 404 Not Found errors that occur when calling a service. For this we'll need a custom error https://wearestac.com/blog/raising-and-rescuing-custom-errors-in-rails class that extends StandardError. # lib/errors/not_found.rb module Errors class NotFound < StandardError; end end Faraday provides a neat Rack-esque middleware feature. By creating our own custom middleware we can catch any Faraday 404s and raise our custom error. Furthermore, we can re-use the middleware anytime we need the same behaviour. # lib/errors/raise_error.rb module Errors class RaiseError < Faraday::Response::Middleware def on_complete(env) raise Errors::NotFound if env[:status] == 404 end end end Now for the proxy controller. # app/controllers/proxy_controller.rb class ProxyController < ApplicationController def index connection = Faraday.new(:url => 'http://someservice') do |f| f.adapter Faraday.default_adapter f.use Errors::RaiseError # Include custom middleware end response = connection.get('/some/resource') render :text => response.body end end At this point any NotFounds raised will still result in a 500 Internal Server Error in Rails. To alleviate this let's create a module that uses rescue_from, catches any custom NotFounds and renders the default 404 page. # lib/errors/rescue_error.rb module Errors module RescueError def self.included(base) base.rescue_from Errors::NotFound do |e| render "public/404", :status => 404 end end end end We can then mixin RescueError into our application controller and handle NotFounds app-wide. # app/controllers/application_controller.rb class ApplicationController < ActionController::Base include Errors::RescueError end Unprocessible Entity and Internal Server Error Next, let's create custom errors to help us manage proxy 422s and 500s. # lib/errors/internal_server_error.rb module Error
in realizing this i18n interface and with this article I don't want to attack them in any way. You may want to read Sven Fuchs' writeup on rails raise the Rails i18n features first in order to better understand some parts of the article. The Stumbling Block A few days ago when I tried to implement the i18n functionality for Rails' Date and Time raise custom exception classes I stumbled across an interesting part in the i18n source or, to be more specific, in the simple backend's localize method: def localize(locale, object, format = :default) raise ArgumentError, "Object must be a Date, DateTime or Time object. #{object.inspect} given." unless object.respond_to?(:strftime) type = object.respond_to?(:sec) ? 'time' : 'date' formats = translate(locale, :"#{type}