Rails Raise Standard 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 standard error 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
Rails Exceptions
this 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) f
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Ruby Rescue Standarderror
Learn more about Stack Overflow the company Business Learn more about hiring developers rails rescue exception message or posting ads with us Stack Overflow Questions Jobs Documentation Tags Users Badges Ask Question x Dismiss Join the Stack rails raise internal server error Overflow Community Stack Overflow is a community of 6.2 million programmers, just like you, helping each other. Join them; it only takes a minute: Sign up Difference between Rails 'raise StandardError.new' and 'raise StandardError' http://stackoverflow.com/questions/1918373/how-do-i-raise-an-exception-in-rails-so-it-behaves-like-other-rails-exceptions up vote 1 down vote favorite 1 To handle Rails exceptions, I see people do 'raise SomeException.new' or 'raise SomeException', what are the differences? Say if I have a class class UnableToCreateShipments < StandardError; end Can I do both? raise UnableToCreateShipments raise UnableToCreateShipments.new Or with message raise UnableToCreateShipments, 'my error message' raise UnableToCreateShipments.new('my error message') ruby share|improve this question edited Jul 13 '15 at 4:53 spickermann 38k33561 http://stackoverflow.com/questions/31373514/difference-between-rails-raise-standarderror-new-and-raise-standarderror asked Jul 12 '15 at 23:18 user1883793 1,06741634 1 This is actually Ruby (the language) not Rails (the web framework). –Andrew Grimm Jul 12 '15 at 23:22 add a comment| 1 Answer 1 active oldest votes up vote 3 down vote accepted You can do both, but Boris Batsov's Ruby Style Guide and RuboCop recommend the simpler version of just passing the exception class rather than creating an instance of it. share|improve this answer answered Jul 12 '15 at 23:25 Andrew Grimm 34.4k24124226 add a comment| Your Answer draft saved draft discarded Sign up or log in Sign up using Google Sign up using Facebook Sign up using Email and Password Post as a guest Name Email Post as a guest Name Email discard By posting your answer, you agree to the privacy policy and terms of service. Not the answer you're looking for? Browse other questions tagged ruby or ask your own question. asked 1 year ago viewed 352 times active 1 year ago Blog Stack Overflow Podcast #92 - The Guerilla Guide to Interviewing Related 706A concise explanation of nil v. empty v. blank in Ruby on Rails276Rails :include vs. :joins192Difference between attr_accessor and
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. https://wearestac.com/blog/raising-and-rescuing-custom-errors-in-rails For example, you might have a controller that is acting as a simple proxy http://daniel.fone.net.nz/blog/2013/05/28/why-you-should-never-rescue-exception-in-ruby/ to a third party service such as Twitter or Facebook, and you need any of the HTTP errors encountered when calling those 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 rails raise web application. 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 rails raise standard custom error 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
out exactly what you're trying to rescue and use rescue OneError, AnotherError => e. What’s the deal? A common pattern for rescuing exceptions in Ruby is: def do_some_job! # ... do something ... job_succeeded rescue job_failed end This is fine, but when developers need to capture the exception details, a terrible, terrible thing happens: def do_some_job! # ... do something ... job_succeeded rescue Exception => e job_failed e end I have been caught out by that code on at least three separate occasions. Twice when I wrote it. I write this post in the hope that I (and perhaps others) will finally wise up about exception handling and that my fingers will never, ever type that code again. Just to confirm this is a actually bad practice, here’s ~200k results for rescue Exception => on Github What is this I don’t even… Exception is the root of the exception class hierarchy in Ruby. Everything from signal handling to memory errors will raise a subclass of Exception. Here’s the full list of exceptions from ruby-core that we’ll inadvertently rescue when rescuing Exception. SystemStackError NoMemoryError SecurityError ScriptError NotImplementedError LoadError Gem::LoadError SyntaxError SignalException Interrupt SystemExit Gem::SystemExitException Do you really want to rescue a