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Rose Gold, Gold, Silver, Space Gray
iPhone 6s Plus
Rose Gold, Gold, Silver, Space Gray
iPhone 6s Plus
5.44 inches (138.3 mm)
2.64 inches (67.1 mm)
0.28 inch (7.1 mm)
Weight: 5.04 ounces (143 grams)
6.23 inches (158.2 mm)
3.07 inches (77.9 mm)
0.29 inch (7.3 mm)
iPhone 6s Plus
Weight: 6.77 ounces (192 grams)
Retina HD display with 3D Touch
4.7-inch (diagonal) LED-backlit widescreen
1334-by-750-pixel resolution at 326 ppi
1400:1 contrast ratio (typical)
iPhone 6s Plus
Retina HD display with 3D Touch
5.5-inch (diagonal) LED-backlit widescreen
1920-by-1080-pixel resolution at 401 ppi
1300:1 contrast ratio (typical)
Both models:
500 cd/m2 max brightness (typical)
Full sRGB standard
Dual-domain pixels for wide viewing angles
Fingerprint-resistant oleophobic coating on front
Support for display of multiple languages and characters simultaneously
Display Zoom
Reachability
A9 chip with 64-bit architecture
Embedded M9 motion coprocessor
12-megapixel camera
Live Photos with stabilization
Autofocus with Focus Pixels
Optical image stabilization (iPhone 6s Plus only)
True Tone flash
Panorama (up to 63 megapixels)
Auto HDR for photos
Exposure control
Burst mode
Timer mode
?/2.2 aperture
Five-element lens
5x digital zoom
Hybrid IR filter
Backside illumination sensor
Sapphire crystal lens cover
Auto image stabilization
Local tone mapping
Noise reduction
Face detection
Photo geotagging
4K video recording at 30 fps
1080p HD video recording at 30 fps or 60 fps
720p HD video recording at 30 fps
Optical image stabilization for video (iPhone 6s Plus only)
True Tone flash
Slo-mo video support for 1080p at 120 fps and 720p at 240 fps
Time-lapse video with stabilization
Cinematic video stabilization (1080p and 720p)
Continuous autofocus video
Noise reduction
Take 8-megapixel still photos while recording 4K video
Playback zoom
3x digital zoom
Face detection
Video geotagging
Fingerprint sensor built into the Home button
Pay with your iPhone using Touch ID in stores, within apps, and on the web
Complete purchases made with Apple Pay on your Mac
Receive and redeem rewards using rewards cards
LTE (Bands 1, 2, 3, 4, 5, 7, 8, 12, 13, 17, 18, 19, 20, 25, 26, 27, 28, 29, 30)
TD-LTE (Bands 38, 39, 40, 41)
TD-SCDMA 1900 (F), 2000 (A)
UMTS/HSPA+/DC-HSDPA (850, 900, ,
CDMA EV-DO Rev. A (800, ,
GSM/EDGE (850, 900,
LTE (Bands 1, 2, 3, 4, 5, 7, 8, 12, 13, 17, 18, 19, 20, 25, 26, 27, 28, 29)
TD-LTE (Bands 38, 39, 40, 41)
TD-SCDMA 1900 (F), 2000 (A)
CDMA EV-DO Rev. A (800, ,
UMTS/HSPA+/DC-HSDPA (850, 900, ,
GSM/EDGE (850, 900,
802.11a/b/g/n/ac Wi-Fi with MIMO
Bluetooth 4.2 wireless technology
Assisted GPS and GLONASS
Digital compass
iBeacon microlocation
FaceTime video calling over Wi-Fi or cellular
FaceTime audio
Voice over LTE (VoLTE)4
Wi-Fi calling4
Audio formats supported: AAC (8 to 320 Kbps), Protected AAC (from iTunes Store), HE-AAC, MP3 (8 to 320 Kbps), MP3 VBR, Dolby Digital (AC-3), Dolby Digital Plus (E-AC-3), Audible (formats 2, 3, 4, Audible Enhanced Audio, AAX, and AAX+), Apple Lossless, AIFF, and WAV
User-configurable maximum volume limit
AirPlay Mirroring, photos, audio, and video out to Apple TV (2nd generation or later)
Video mirroring and video out support: Up to 1080p through Lightning Digital AV Adapter and Lightning to VGA Adapter (adapters sold separately)
Video formats supported: H.264 video up to 4K, 30 frames per second, High Profile level 4.2 with AAC-LC audio up to 160 Kbps, 48kHz, stereo audio or Dolby Audio up to 1008 Kbps, 48kHz, stereo or multichannel audio, in .m4v, .mp4, and . MPEG-4 video up to 2.5 Mbps, 640 by 480 pixels, 30 frames per second, Simple Profile with AAC-LC audio up to 160 Kbps per channel, 48kHz, stereo audio or Dolby Audio up to 1008 Kbps, 48kHz, stereo or multichannel audio, in .m4v, .mp4, and . Motion JPEG (M-JPEG) up to 35 Mbps, 1280 by 720 pixels, 30 frames per second, audio in ulaw, PCM stereo audio in .avi file format
Use your voice to send messages, set reminders, and more
Get proactive suggestions
Use hands-free
Listen and identify songs
Touch ID sensor
Volume up/down
Ring/Silent
On/OffSleep/Wake
Lightning connector
Microphones
Built-in speaker
Talk time: Up to 14 hours on 3G
Internet use: Up to 10 hours on 3G, up to 10 hours on LTE, up to 11 hours on Wi-Fi
HD video playback: Up to 11 hours
Audio playback: Up to 50 hours
Standby time: Up to 10 days
iPhone 6s Plus
Talk time: Up to 24 hours on 3G
Internet use: Up to 12 hours on 3G, up to 12 hours on LTE, up to 12 hours on Wi-Fi
HD video playback: Up to 14 hours
Audio playback: Up to 80 hours
Standby time: Up to 16 days
Both models:
Built-in rechargeable lithium-ion battery
Charging via USB to computer system or power adapter
Touch ID fingerprint sensor
Three-axis gyro
Accelerometer
Proximity sensor
Ambient light sensor
With an all-new design and all-new features, iOS 10 is the world’s most advanced mobile OS. It brings your iPhone to life in more intelligent and expressive ways than ever.
Control Center
iCloud Keychain
Multitasking
Night Shift
Notification Center
Spotlight Search
iTunes Store
Calculator
Voice Memos
iCloud Drive
Find My iPhone
Find My Friends
GarageBand
Apple Store
Apple TV Remote
iTunes Remote
Music Memos
iPhone 6s and iPhone 6s Plus are not compatible with existing micro-SIM cards.
iPhone 6s (Model A1633, A1688): M3, T4
iPhone 6s Plus (Model A1634, A1687): M3, T4
Viewable document types
.jpg, .tiff, .gif (images); .doc and .docx (Microsoft Word); .htm and .html (web pages); .key (Keynote); .numbers (Numbers); .pages (Pages); .pdf (Preview and Adobe Acrobat); .ppt and .pptx (Microsoft PowerPoint); .txt (text); .rtf (rich text format); .vcf (contact information); .xls and .xlsx (Microsoft Excel); . .ics
Apple ID (required for some features)
Internet access8
Syncing with iTunes on a Mac or PC requires:
Mac: OS X v10.8.5 or later
PC: Windows 7 or later
iTunes 12.3 or later (free download from )
Operating ambient temperature: 32° to 95° F (0° to 35° C)
Nonoperating temperature: -4° to 113° F (-20° to 45° C)
Relative humidity: 5% to 95% noncondensing
Operating altitude: tested up to 10,000 feet (3000 m)
Language support
English (Australia, Canada, UK, U.S.), Chinese (Simplified, Traditional, Traditional Hong Kong), French (Canada, France), German, Italian, Japanese, Korean, Spanish (Latin America, Mexico, Spain), Arabic, Catalan, Croatian, Czech, Danish, Dutch, Finnish, Greek, Hebrew, Hindi, Hungarian, Indonesian, Malay, Norwegian, Polish, Portuguese (Brazil, Portugal), Romanian, Russian, Slovak, Swedish, Thai, Turkish, Ukrainian, Vietnamese
QuickType keyboard support
English (Australia, Canada, India, Singapore, UK, U.S.), Chinese - Simplified (Handwriting, Pinyin, Stroke), Chinese - Traditional (Cangjie, Handwriting, Pinyin, Stroke, Sucheng, Zhuyin), French (Belgium, Canada, France, Switzerland), German (Austria, Germany, Switzerland), Italian, Japanese (Kana, Romaji), Korean, Spanish (Latin America, Mexico, Spain), Arabic, Bengali, Bulgarian, Catalan, Cherokee, Croatian, Czech, Danish, Dutch, Emoji, Estonian, Filipino, Finnish, Flemish, Greek, Gujarati, Hawaiian, Hebrew, Hindi (Devanagari, Transliteration), Hinglish, Hungarian, Icelandic, Indonesian, Latvian, Lithuanian, Macedonian, Malay, Marathi, Norwegian, Polish, Portuguese (Brazil, Portugal), Punjabi, Romanian, Russian, Serbian (Cyrillic, Latin), Slovak, Slovenian, Swedish, Tamil (Script, Transliteration), Telugu, Thai, Turkish, Ukrainian, Urdu, Vietnamese
QuickType keyboard support with predictive input9
English (Australia, Canada, India, Singapore, UK, U.S.), Chinese (Simplified, Traditional), French (Belgium, Canada, France, Switzerland), German (Austria, Germany, Switzerland), Italian, Japanese, Korean, Russian, Spanish (Latin America, Mexico, Spain), Portuguese (Brazil, Portugal), Thai, Turkish
Siri languages
English (Australia, Canada, India, Ireland, New Zealand, Singapore, South Africa, UK, U.S.), Spanish (Chile, Mexico, Spain, U.S.), French (Belgium, Canada, France, Switzerland), German (Austria, Germany, Switzerland), Italian (Italy, Switzerland), Japanese, Korean, Mandarin (Mainland China, Taiwan), Cantonese (Mainland China, Hong Kong), Arabic (Saudi Arabia, United Arab Emirates), Danish (Denmark), Dutch (Belgium, Netherlands), Finnish (Finland), Hebrew (Israel), Malay (Malaysia), Norwegian (Norway), Russian (Russia), Swedish (Sweden), Turkish (Turkey), Thai (Thailand), Portuguese (Brazil)
Dictation languages
English (Australia, Canada, India, Ireland, Malaysia, New Zealand, Philippines, Saudi Arabia, Singapore, South Africa, UAE, UK, U.S.), Spanish (Chile, Colombia, Mexico, Spain, U.S.), French (Belgium, Canada, France, Luxembourg, Switzerland), German (Austria, Germany, Switzerland), Italian (Italy, Switzerland), Japanese, Korean, Mandarin (Mainland China, Taiwan), Cantonese (Hong Kong), Arabic (Kuwait, Saudi Arabia, Qatar, UAE), Catalan, Croatian, Czech, Danish, Dutch (Belgium, Luxembourg, Netherlands), Finnish, Greek, Hebrew, Hungarian, Indonesian, Malaysian, Norwegian, Polish, Portuguese (Brazil, Portugal), Romanian, Russian, Slovakian, Swedish, Turkish, Thai, Ukrainian, Vietnamese
Definition dictionary support
English, Chinese (Simplified, Traditional), Danish, Dutch, French, German, Hindi, Italian, Japanese, Korean, Norwegian, Portuguese (Brazil), Russian, Spanish, Swedish, Thai, Turkish
Bilingual dictionary support
Chinese (Simplified), Dutch, French, German, Italian, Japanese, Korean, Spanish
Spell check
English (Australia, Canada, UK, U.S.), French, German, Italian, Spanish, Danish, Dutch, Finnish, Korean, Norwegian, Polish, Portuguese (Brazil, Portugal), Russian, Swedish, Turkish
iPhone with iOS 10
EarPods with 3.5 mm Headphone Plug
Lightning to USB Cable
USB Power Adapter
Documentation
Mercury-free LED-backlit display
Arsenic-free display glass
Brominated flame retardant–free
Beryllium-free
Recyclable aluminum enclosure
Power adapter outperforms strictest global energy efficiency standards
Speaker enclosure with 30 percent post-consumer recycled plastic
about Apple’s dedication to reducing the environmental impact of our products and process. Or read our
for detailed information on the environmental performance of every Apple product.
Apple takes a holistic view of materials management and waste minimization.A Guide for Upgrading Ruby on Rails — Ruby on Rails Guides
A Guide for Upgrading Ruby on RailsThis guide provides steps to be followed when you upgrade your applications to a newer version of Ruby on Rails. These steps are also available in individual release guides.
1 General AdviceBefore attempting to upgrade an existing application, you should be sure you have a good reason to upgrade. You need to balance several factors: the need for new features, the increasing difficulty of finding support for old code, and your available time and skills, to name a few.1.1 Test CoverageThe best way to be sure that your application still works after upgrading is to have good test coverage before you start the process. If you don't have automated tests that exercise the bulk of your application, you'll need to spend time manually exercising all the parts that have changed. In the case of a Rails upgrade, that will mean every single piece of functionality in the application. Do yourself a favor and make sure your test coverage is good before you start an upgrade.1.2 The Upgrade ProcessWhen changing Rails versions, it's best to move slowly, one minor version at a time, in order to make good use of the deprecation warnings. Rails version numbers are in the form Major.Minor.Patch. Major and Minor versions are allowed to make changes to the public API, so this may cause errors in your application. Patch versions only include bug fixes, and don't change any public API.The process should go as follows:
Write tests and make sure they pass.
Move to the latest patch version after your current version.
Fix tests and deprecated features.
Move to the latest patch version of the next minor version.
Repeat this process until you reach your target Rails version. Each time you move versions, you will need to change the Rails version number in the Gemfile (and possibly other gem versions) and run bundle update. Then run the Update task mentioned below to update configuration files, then run your tests.You can find a list of all released Rails versions .1.3 Ruby VersionsRails generally stays close to the latest released Ruby version when it's released:
Rails 5 requires Ruby 2.2.2 or newer.
Rails 4 prefers Ruby 2.0 and requires 1.9.3 or newer.
Rails 3.2.x is the last branch to support Ruby 1.8.7.
Rails 3 and above require Ruby 1.8.7 or higher. Support for all of the previous Ruby versions has been dropped officially. You should upgrade as early as possible.
Rails provides the app:update task (rails:update on 4.2 and earlier). After updating the Rails version
in the Gemfile, run this task.
This will help you with the creation of new files and changes of old files in an
interactive session.
$ rails app:update
config/boot.rb
config/routes.rb
Overwrite /myapp/config/routes.rb? (enter "h" for help) [Ynaqdh]
config/routes.rb
config/application.rb
Overwrite /myapp/config/application.rb? (enter "h" for help) [Ynaqdh]
config/application.rb
config/environment.rb
Don't forget to review the difference, to see if there were any unexpected changes.2 Upgrading from Rails 4.2 to Rails 5.0For more information on changes made to Rails 5.0 please see the .2.1 Ruby 2.2.2+ requiredFrom Ruby on Rails 5.0 onwards, Ruby 2.2.2+ is the only supported Ruby version.
Make sure you are on Ruby 2.2.2 version or greater, before you proceed.2.2 Active Record Models Now Inherit from ApplicationRecord by DefaultIn Rails 4.2, an Active Record model inherits from ActiveRecord::Base. In Rails 5.0,
all models inherit from ApplicationRecord.ApplicationRecord is a new superclass for all app models, analogous to app
controllers subclassing ApplicationController instead of
ActionController::Base. This gives apps a single spot to configure app-wide
model behavior.When upgrading from Rails 4.2 to Rails 5.0, you need to create an
application_record.rb file in app/models/ and add the following content:
class ApplicationRecord & ActiveRecord::Base
self.abstract_class = true
2.3 Halting Callback Chains via throw(:abort)
In Rails 4.2, when a 'before' callback returns false in Active Record
and Active Model, then the entire callback chain is halted. In other words,
successive 'before' callbacks are not executed, and neither is the action wrapped
in callbacks.In Rails 5.0, returning false in an Active Record or Active Model callback
will not have this side effect of halting the callback chain. Instead, callback
chains must be explicitly halted by calling throw(:abort).When you upgrade from Rails 4.2 to Rails 5.0, returning false in those kind of
callbacks will still halt the callback chain, but you will receive a deprecation
warning about this upcoming change.When you are ready, you can opt into the new behavior and remove the deprecation
warning by adding the following configuration to your config/application.rb:
ActiveSupport.halt_callback_chains_on_return_false = false
Note that this option will not affect Active Support callbacks since they never
halted the chain when any value was returned.See
for more details.2.4 ActiveJob Now Inherits from ApplicationJob by DefaultIn Rails 4.2, an Active Job inherits from ActiveJob::Base. In Rails 5.0, this
behavior has changed to now inherit from ApplicationJob.When upgrading from Rails 4.2 to Rails 5.0, you need to create an
application_job.rb file in app/jobs/ and add the following content:
class ApplicationJob & ActiveJob::Base
Then make sure that all your job classes inherit from it.See
for more details.2.5 Rails Controller Testingassigns and assert_template have been extracted to the rails-controller-testing gem. To
continue using these methods in your controller tests, add gem 'rails-controller-testing' to
your Gemfile.If you are using Rspec for testing, please see the extra configuration required in the gem's
documentation.2.6 Autoloading is Disabled After Booting in the Production EnvironmentAutoloading is now disabled after booting in the production environment by
default.Eager loading the application is part of the boot process, so top-level
constants are fine and are still autoloaded, no need to require their files.Constants in deeper places only executed at runtime, like regular method bodies,
are also fine because the file defining them will have been eager loaded while booting.For the vast majority of applications this change needs no action. But in the
very rare event that your application needs autoloading while running in
production mode, set Rails.application.config.enable_dependency_loading to
true.2.7 XML SerializationActiveModel::Serializers::Xml has been extracted from Rails to the activemodel-serializers-xml
gem. To continue using XML serialization in your application, add gem 'activemodel-serializers-xml'
to your Gemfile.2.8 Removed Support for Legacy mysql Database AdapterRails 5 removes support for the legacy mysql database adapter. Most users should be able to
use mysql2 instead. It will be converted to a separate gem when we find someone to maintain
it.2.9 Removed Support for Debuggerdebugger is not supported by Ruby 2.2 which is required by Rails 5. Use byebug instead.2.10 Use bin/rails for running tasks and testsRails 5 adds the ability to run tasks and tests through bin/rails instead of rake. Generally
these changes are in parallel with rake, but some were ported over altogether.To use the new test runner simply type bin/rails test.rake dev:cache is now rails dev:cache.Run bin/rails to see the list of commands available.2.11 ActionController::Parameters No Longer Inherits from HashWithIndifferentAccess
Calling params in your application will now return an object instead of a hash. If your
parameters are already permitted, then you will not need to make any changes. If you are using slice
and other methods that depend on being able to read the hash regardless of permitted? you will
need to upgrade your application to first permit and then convert to a hash.
params.permit([:proceed_to, :return_to]).to_h
2.12 protect_from_forgery Now Defaults to prepend: false
protect_from_forgery defaults to prepend: false which means that it will be inserted into
the callback chain at the point in which you call it in your application. If you want
protect_from_forgery to always run first, then you should change your application to use
protect_from_forgery prepend: true.2.13 Default Template Handler is Now RAWFiles without a template handler in their extension will be rendered using the raw handler.
Previously Rails would render files using the ERB template handler.If you do not want your file to be handled via the raw handler, you should add an extension
to your file that can be parsed by the appropriate template handler.2.14 Added Wildcard Matching for Template DependenciesYou can now use wildcard matching for your template dependencies. For example, if you were
defining your templates as such:
&% # Template Dependency: recordings/threads/events/subscribers_changed %&
&% # Template Dependency: recordings/threads/events/completed %&
&% # Template Dependency: recordings/threads/events/uncompleted %&
You can now just call the dependency once with a wildcard.
&% # Template Dependency: recordings/threads/events/* %&
2.15 Removed Support for protected_attributes GemThe protected_attributes gem is no longer supported in Rails 5.2.16 Removed support for activerecord-deprecated_finders gemThe activerecord-deprecated_finders gem is no longer supported in Rails 5.2.17 ActiveSupport::TestCase Default Test Order is Now RandomWhen tests are run in your application, the default order is now :random
instead of :sorted. Use the following config option to set it back to :sorted.
# config/environments/test.rb
Rails.application.configure do
config.active_support.test_order = :sorted
2.18 ActionController::Live became a Concern
If you include ActionController::Live in another module that is included in your controller, then you
should also extend the module with ActiveSupport::Concern. Alternatively, you can use the self.included hook
to include ActionController::Live directly to the controller once the StreamingSupport is included.This means that if your application used to have its own streaming module, the following code
would break in production mode:
# This is a work-around for streamed controllers performing authentication with Warden/Devise.
# See /plataformatec/devise/issues/2332
# Authenticating in the router is another solution as suggested in that issue
class StreamingSupport
include ActionController::Live # this won't work in production for Rails 5
# extend ActiveSupport::Concern # unless you uncomment this line.
def process(name)
super(name)
rescue ArgumentError =& e
if e.message == 'uncaught throw :warden'
throw :warden
2.19 New Framework Defaults2.19.1 Active Record belongs_to Required by Default Optionbelongs_to will now trigger a validation error by default if the association is not present.This can be turned off per-association with optional: true.This default will be automatically configured in new applications. If existing application
want to add this feature it will need to be turned on in an initializer.
config.active_record.belongs_to_required_by_default = true
2.19.2 Per-form CSRF TokensRails 5 now supports per-form CSRF tokens to mitigate against code-injection attacks with forms
created by JavaScript. With this option turned on, forms in your application will each have their
own CSRF token that is specified to the action and method for that form.
config.action_controller.per_form_csrf_tokens = true
2.19.3 Forgery Protection with Origin CheckYou can now configure your application to check if the HTTP Origin header should be checked
against the site's origin as an additional CSRF defense. Set the following in your config to
config.action_controller.forgery_protection_origin_check = true
2.19.4 Allow Configuration of Action Mailer Queue NameThe default mailer queue name is mailers. This configuration option allows you to globally change
the queue name. Set the following in your config:
config.action_mailer.deliver_later_queue_name = :new_queue_name
2.19.5 Support Fragment Caching in Action Mailer ViewsSet config.action_mailer.perform_caching in your config to determine whether your Action Mailer views
should support caching.
config.action_mailer.perform_caching = true
2.19.6 Configure the Output of db:structure:dump
If you're using schema_search_path or other PostgreSQL extentions, you can control how the schema is
dumped. Set to :all to generate all dumps, or to :schema_search_path to generate from schema search path.
config.active_record.dump_schemas = :all
2.19.7 Configure SSL Options to Enable HSTS with SubdomainsSet the following in your config to enable HSTS when using subdomains:
config.ssl_options = { hsts: { subdomains: true } }
When using Ruby 2.4, you can preserve the timezone of the receiver when calling to_time.
ActiveSupport.to_time_preserves_timezone = false
3 Upgrading from Rails 4.1 to Rails 4.23.1 Web ConsoleFirst, add gem 'web-console', '~& 2.0' to the :development group in your Gemfile and run bundle install (it won't have been included when you upgraded Rails). Once it's been installed, you can simply drop a reference to the console helper (i.e., &%= console %&) into any view you want to enable it for. A console will also be provided on any error page you view in your development environment.3.2 Respondersrespond_with and the class-level respond_to methods have been extracted to the responders gem. To use them, simply add gem 'responders', '~& 2.0' to your Gemfile. Calls to respond_with and respond_to (again, at the class level) will no longer work without having included the responders gem in your dependencies:
# app/controllers/users_controller.rb
class UsersController & ApplicationController
respond_to :html, :json
@user = User.find(params[:id])
respond_with @user
Instance-level respond_to is unaffected and does not require the additional gem:
# app/controllers/users_controller.rb
class UsersController & ApplicationController
@user = User.find(params[:id])
respond_to do |format|
format.html
format.json { render json: @user }
for more details.3.3 Error handling in transaction callbacksCurrently, Active Record suppresses errors raised
within after_rollback or after_commit callbacks and only prints them to
the logs. In the next version, these errors will no longer be suppressed.
Instead, the errors will propagate normally just like in other Active
Record callbacks.When you define an after_rollback or after_commit callback, you
will receive a deprecation warning about this upcoming change. When
you are ready, you can opt into the new behavior and remove the
deprecation warning by adding following configuration to your
config/application.rb:
config.active_record.raise_in_transactional_callbacks = true
for more details.3.4 Ordering of test casesIn Rails 5.0, test cases will be executed in random order by default. In
anticipation of this change, Rails 4.2 introduced a new configuration option
active_support.test_order for explicitly specifying the test ordering. This
allows you to either lock down the current behavior by setting the option to
:sorted, or opt into the future behavior by setting the option to :random.If you do not specify a value for this option, a deprecation warning will be
emitted. To avoid this, add the following line to your test environment:
# config/environments/test.rb
Rails.application.configure do
config.active_support.test_order = :sorted # or `:random` if you prefer
3.5 Serialized attributesWhen using a custom coder (e.g. serialize :metadata, JSON),
assigning nil to a serialized attribute will save it to the database
as NULL instead of passing the nil value through the coder (e.g. "null"
when using the JSON coder).3.6 Production log levelIn Rails 5, the default log level for the production environment will be changed
to :debug (from :info). To preserve the current default, add the following
line to your production.rb:
# Set to `:info` to match the current default, or set to `:debug` to opt-into
# the future default.
config.log_level = :info
3.7 after_bundle in Rails templatesIf you have a Rails template that adds all the files in version control, it
fails to add the generated binstubs because it gets executed before Bundler:
# template.rb
generate(:scaffold, "person name:string")
route "root to: 'people#index'"
rake("db:migrate")
git add: "."
git commit: %Q{ -m 'Initial commit' }
You can now wrap the git calls in an after_bundle block. It will be run
after the binstubs have been generated.
# template.rb
generate(:scaffold, "person name:string")
route "root to: 'people#index'"
rake("db:migrate")
after_bundle do
git add: "."
git commit: %Q{ -m 'Initial commit' }
3.8 Rails HTML SanitizerThere's a new choice for sanitizing HTML fragments in your applications. The
venerable html-scanner approach is now officially being deprecated in favor of
.This means the methods sanitize, sanitize_css, strip_tags and
strip_links are backed by a new implementation.This new sanitizer uses
internally. Loofah in turn uses Nokogiri, which
wraps XML parsers written in both C and Java, so sanitization should be faster
no matter which Ruby version you run.The new version updates sanitize, so it can take a Loofah::Scrubber for
powerful scrubbing.
.Two new scrubbers have also been added: PermitScrubber and TargetScrubber.
for more information.The documentation for PermitScrubber and TargetScrubber explains how you
can gain complete control over when and how elements should be stripped.If your application needs to use the old sanitizer implementation, include rails-deprecated_sanitizer in your Gemfile:
gem 'rails-deprecated_sanitizer'
3.9 Rails DOM TestingThe
(containing methods such as assert_tag),
in favor of the assert_select methods from the SelectorAssertions module, which has been extracted into the .3.10 Masked Authenticity TokensIn order to mitigate SSL attacks, form_authenticity_token is now masked so that it varies with each request.
Thus, tokens are validated by unmasking and then decrypting.
As a result, any strategies for verifying requests from non-rails forms that relied on a static session CSRF token have to take this into account.3.11 Action MailerPreviously, calling a mailer method on a mailer class will result in the
corresponding instance method being executed directly. With the introduction of
Active Job and #deliver_later, this is no longer true. In Rails 4.2, the
invocation of the instance methods are deferred until either deliver_now or
deliver_later is called. For example:
class Notifier & ActionMailer::Base
def notify(user, ...)
puts "Called"
mail(to: user.email, ...)
mail = Notifier.notify(user, ...) # Notifier#notify is not yet called at this point
mail = mail.deliver_now
# Prints "Called"
This should not result in any noticeable differences for most applications.
However, if you need some non-mailer methods to be executed synchronously, and
you were previously relying on the synchronous proxying behavior, you should
define them as class methods on the mailer class directly:
class Notifier & ActionMailer::Base
def self.broadcast_notifications(users, ...)
users.each { |user| Notifier.notify(user, ...) }
3.12 Foreign Key SupportThe migration DSL has been expanded to support foreign key definitions. If
you've been using the Foreigner gem, you might want to consider removing it.
Note that the foreign key support of Rails is a subset of Foreigner. This means
that not every Foreigner definition can be fully replaced by its Rails
migration DSL counterpart.The migration procedure is as follows:
remove gem "foreigner" from the Gemfile.
run bundle install.
run bin/rake db:schema:dump.
make sure that db/schema.rb contains every foreign key definition with
the necessary options.
4 Upgrading from Rails 4.0 to Rails 4.1Or, "whaaat my tests are failing!!!?" or "my &script& widget is busted!!"Cross-site request forgery (CSRF) protection now covers GET requests with
JavaScript responses, too. This prevents a third-party site from remotely
referencing your JavaScript with a &script& tag to extract sensitive data.This means that your functional and integration tests that use
get :index, format: :js
will now trigger CSRF protection. Switch to
xhr :get, :index, format: :js
to explicitly test an XmlHttpRequest.Note: Your own &script& tags are treated as cross-origin and blocked by
default, too. If you really mean to load JavaScript from &script& tags,
you must now explicitly skip CSRF protection on those actions.4.2 SpringIf you want to use Spring as your application preloader you need to:
Add gem 'spring', group: :development to your Gemfile.
Install spring using bundle install.
Springify your binstubs with bundle exec spring binstub --all.
User defined rake tasks will run in the development environment by
default. If you want them to run in other environments consult the
.4.3 config/secrets.yml
If you want to use the new secrets.yml convention to store your application's
secrets, you need to:
Create a secrets.yml file in your config folder with the following content:
development:
secret_key_base:
secret_key_base:
production:
secret_key_base: &%= ENV["SECRET_KEY_BASE"] %&
Use your existing secret_key_base from the secret_token.rb initializer to
set the SECRET_KEY_BASE environment variable for whichever users running the
Rails application in production mode. Alternatively, you can simply copy the existing
secret_key_base from the secret_token.rb initializer to secrets.yml
under the production section, replacing '&%= ENV["SECRET_KEY_BASE"] %&'.
Remove the secret_token.rb initializer.
Use rake secret to generate new keys for the development and test sections.
Restart your server.
4.4 Changes to test helperIf your test helper contains a call to
ActiveRecord::Migration.check_pending! this can be removed. The check
is now done automatically when you require 'rails/test_help', although
leaving this line in your helper is not harmful in any way.4.5 Cookies serializerApplications created before Rails 4.1 uses Marshal to serialize cookie values into
the signed and encrypted cookie jars. If you want to use the new JSON-based format
in your application, you can add an initializer file with the following content:
Rails.application.config.action_dispatch.cookies_serializer = :hybrid
This would transparently migrate your existing Marshal-serialized cookies into the
new JSON-based format.When using the :json or :hybrid serializer, you should beware that not all
Ruby objects can be serialized as JSON. For example, Date and Time objects
will be serialized as strings, and Hashes will have their keys stringified.
class CookiesController & ApplicationController
def set_cookie
cookies.encrypted[:expiration_date] = Date.tomorrow # =& Thu, 20 Mar 2014
redirect_to action: 'read_cookie'
def read_cookie
cookies.encrypted[:expiration_date] # =& ""
It's advisable that you only store simple data (strings and numbers) in cookies.
If you have to store complex objects, you would need to handle the conversion
manually when reading the values on subsequent requests.If you use the cookie session store, this would apply to the session and
flash hash as well.4.6 Flash structure changesFlash message keys are
can still be accessed using either symbols or strings. Looping through the flash
will always yield string keys:
flash["string"] = "a string"
flash[:symbol] = "a symbol"
# Rails & 4.1
flash.keys # =& ["string", :symbol]
# Rails &= 4.1
flash.keys # =& ["string", "symbol"]
Make sure you are comparing Flash message keys against strings.4.7 Changes in JSON handlingThere are a few major changes related to JSON handling in Rails 4.1.4.7.1 MultiJSON removalMultiJSON has reached its
and has been removed from Rails.If your application currently depend on MultiJSON directly, you have a few options:
Add 'multi_json' to your Gemfile. Note that this might cease to work in the future
Migrate away from MultiJSON by using obj.to_json, and JSON.parse(str) instead.
Do not simply replace MultiJson.dump and MultiJson.load with
JSON.dump and JSON.load. These JSON gem APIs are meant for serializing and
deserializing arbitrary Ruby objects and are generally .4.7.2 JSON gem compatibilityHistorically, Rails had some compatibility issues with the JSON gem. Using
JSON.generate and JSON.dump inside a Rails application could produce
unexpected errors.Rails 4.1 fixed these issues by isolating its own encoder from the JSON gem. The
JSON gem APIs will function as normal, but they will not have access to any
Rails-specific features. For example:
class FooBar
def as_json(options = nil)
{ foo: 'bar' }
&& FooBar.new.to_json # =& "{\"foo\":\"bar\"}"
&& JSON.generate(FooBar.new, quirks_mode: true) # =& "\"#&FooBar:0x007fa80a481610&\""
4.7.3 New JSON encoderThe JSON encoder in Rails 4.1 has been rewritten to take advantage of the JSON
gem. For most applications, this should be a transparent change. However, as
part of the rewrite, the following features have been removed from the encoder:
Circular data structure detection
Support for the encode_json hook
Option to encode BigDecimal objects as numbers instead of strings
If your application depends on one of these features, you can get them back by
adding the
gem to your Gemfile.#as_json for objects with time component (Time, DateTime, ActiveSupport::TimeWithZone)
now returns millisecond precision by default. If you need to keep old behavior with no millisecond
precision, set the following in an initializer:
ActiveSupport::JSON::Encoding.time_precision = 0
4.8 Usage of return within inline callback blocksPreviously, Rails allowed inline callback blocks to use return this way:
class ReadOnlyModel & ActiveRecord::Base
before_save { return false } # BAD
This behavior was never intentionally supported. Due to a change in the internals
of ActiveSupport::Callbacks, this is no longer allowed in Rails 4.1. Using a
return statement in an inline callback block causes a LocalJumpError to
be raised when the callback is executed.Inline callback blocks using return can be refactored to evaluate to the
returned value:
class ReadOnlyModel & ActiveRecord::Base
before_save { false } # GOOD
Alternatively, if return is preferred it is recommended to explicitly define
class ReadOnlyModel & ActiveRecord::Base
before_save :before_save_callback # GOOD
def before_save_callback
return false
This change applies to most places in Rails where callbacks are used, including
Active Record and Active Model callbacks, as well as filters in Action
Controller (e.g. before_action).See
details.4.9 Methods defined in Active Record fixturesRails 4.1 evaluates each fixture's ERB in a separate context, so helper methods
defined in a fixture will not be available in other fixtures.Helper methods that are used in multiple fixtures should be defined on modules
included in the newly introduced ActiveRecord::FixtureSet.context_class, in
test_helper.rb.
module FixtureFileHelpers
def file_sha(path)
Digest::SHA2.hexdigest(File.read(Rails.root.join('test/fixtures', path)))
ActiveRecord::FixtureSet.context_class.include FixtureFileHelpers
4.10 I18n enforcing available localesRails 4.1 now defaults the I18n option enforce_available_locales to true. This
means that it will make sure that all locales passed to it must be declared in
the available_locales list.To disable it (and allow I18n to accept any locale option) add the following
configuration to your application:
config.i18n.enforce_available_locales = false
Note that this option was added as a security measure, to ensure user input
cannot be used as locale information unless it is previously known. Therefore,
it's recommended not to disable this option unless you have a strong reason for
doing so.4.11 Mutator methods called on RelationRelation no longer has mutator methods like #map! and #delete_if. Convert
to an Array by calling #to_a before using these methods.It intends to prevent odd bugs and confusion in code that call mutator
methods directly on the Relation.
# Instead of this
Author.where(name: 'Hank Moody').compact!
# Now you have to do this
authors = Author.where(name: 'Hank Moody').to_pact!
4.12 Changes on Default ScopesDefault scopes are no longer overridden by chained conditions.In previous versions when you defined a default_scope in a model
it was overridden by chained conditions in the same field. Now it
is merged like any other scope.Before:
class User & ActiveRecord::Base
default_scope { where state: 'pending' }
scope :active, -& { where state: 'active' }
scope :inactive, -& { where state: 'inactive' }
# SELECT "users".* FROM "users" WHERE "users"."state" = 'pending'
User.active
# SELECT "users".* FROM "users" WHERE "users"."state" = 'active'
User.where(state: 'inactive')
# SELECT "users".* FROM "users" WHERE "users"."state" = 'inactive'
class User & ActiveRecord::Base
default_scope { where state: 'pending' }
scope :active, -& { where state: 'active' }
scope :inactive, -& { where state: 'inactive' }
# SELECT "users".* FROM "users" WHERE "users"."state" = 'pending'
User.active
# SELECT "users".* FROM "users" WHERE "users"."state" = 'pending' AND "users"."state" = 'active'
User.where(state: 'inactive')
# SELECT "users".* FROM "users" WHERE "users"."state" = 'pending' AND "users"."state" = 'inactive'
To get the previous behavior it is needed to explicitly remove the
default_scope condition using unscoped, unscope, rewhere or
class User & ActiveRecord::Base
default_scope { where state: 'pending' }
scope :active, -& { unscope(where: :state).where(state: 'active') }
scope :inactive, -& { rewhere state: 'inactive' }
# SELECT "users".* FROM "users" WHERE "users"."state" = 'pending'
User.active
# SELECT "users".* FROM "users" WHERE "users"."state" = 'active'
User.inactive
# SELECT "users".* FROM "users" WHERE "users"."state" = 'inactive'
4.13 Rendering content from stringRails 4.1 introduces :plain, :html, and :body options to render. Those
options are now the preferred way to render string-based content, as it allows
you to specify which content type you want the response sent as.
render :plain will set the content type to text/plain
render :html will set the content type to text/html
render :body will not set the content type header.
From the security standpoint, if you don't expect to have any markup in your
response body, you should be using render :plain as most browsers will escape
unsafe content in the response for you.We will be deprecating the use of render :text in a future version. So please
start using the more precise :plain, :html, and :body options instead.
Using render :text may pose a security risk, as the content is sent as
text/html.4.14 PostgreSQL json and hstore datatypesRails 4.1 will map json and hstore columns to a string-keyed Ruby Hash.
In earlier versions, a HashWithIndifferentAccess was used. This means that
symbol access is no longer supported. This is also the case for
store_accessors based on top of json or hstore columns. Make sure to use
string keys consistently.4.15 Explicit block use for ActiveSupport::Callbacks
Rails 4.1 now expects an explicit block to be passed when calling
ActiveSupport::Callbacks.set_callback. This change stems from
ActiveSupport::Callbacks being largely rewritten for the 4.1 release.
# Previously in Rails 4.0
set_callback :save, :around, -&(r, &block) { result = block. stuff }
# Now in Rails 4.1
set_callback :save, :around, -&(r, block) { result = block. stuff }
5 Upgrading from Rails 3.2 to Rails 4.0If your application is currently on any version of Rails older than 3.2.x, you should upgrade to Rails 3.2 before attempting one to Rails 4.0.The following changes are meant for upgrading your application to Rails 4.0.5.1 HTTP PATCHRails 4 now uses PATCH as the primary HTTP verb for updates when a RESTful
resource is declared in config/routes.rb. The update action is still used,
and PUT requests will continue to be routed to the update action as well.
So, if you're using only the standard RESTful routes, no changes need to be made:
resources :users
&%= form_for @user do |f| %&
class UsersController & ApplicationController
def update
# N PATCH will be preferred, and PUT will still work.
However, you will need to make a change if you are using form_for to update
a resource in conjunction with a custom route using the PUT HTTP method:
resources :users, do
put :update_name, on: :member
&%= form_for [ :update_name, @user ] do |f| %&
class UsersController & ApplicationController
def update_name
# C form_for will try to use a non-existent PATCH route.
If the action is not being used in a public API and you are free to change the
HTTP method, you can update your route to use patch instead of put:PUT requests to /users/:id in Rails 4 get routed to update as they are
today. So, if you have an API that gets real PUT requests it is going to work.
The router also routes PATCH requests to /users/:id to the update action.
resources :users do
patch :update_name, on: :member
If the action is being used in a public API and you can't change to HTTP method
being used, you can update your form to use the PUT method instead:
&%= form_for [ :update_name, @user ], method: :put do |f| %&
For more on PATCH and why this change was made, see
on the Rails blog.5.1.1 A note about media typesThe errata for the PATCH verb . One
such format is . While Rails
does not support JSON Patch natively, it's easy enough to add support:
# in your controller
def update
respond_to do |format|
format.json do
# perform a partial update
@article.update params[:article]
format.json_patch do
# perform sophisticated change
# In config/initializers/json_patch.rb:
Mime::Type.register 'application/json-patch+json', :json_patch
As JSON Patch was only recently made into an RFC, there aren't a lot of great
Ruby libraries yet. Aaron Patterson's
is one such gem, but doesn't have
full support for the last few changes in the specification.5.2 GemfileRails 4.0 removed the assets group from Gemfile. You'd need to remove that
line from your Gemfile when upgrading. You should also update your application
file (in config/application.rb):
# Require the gems listed in Gemfile, including any gems
# you've limited to :test, :development, or :production.
Bundler.require(*Rails.groups)
5.3 vendor/pluginsRails 4.0 no longer supports loading plugins from vendor/plugins. You must replace any plugins by extracting them to gems and adding them to your Gemfile. If you choose not to make them gems, you can move them into, say, lib/my_plugin/* and add an appropriate initializer in config/initializers/my_plugin.rb.5.4 Active Record
Rails 4.0 has removed the identity map from Active Record, due to . If you have manually enabled it in your application, you will have to remove the following config that has no effect anymore: config.active_record.identity_map.
The delete method in collection associations can now receive Integer or String arguments as record ids, besides records, pretty much like the destroy method does. Previously it raised ActiveRecord::AssociationTypeMismatch for such arguments. From Rails 4.0 on delete automatically tries to find the records matching the given ids before deleting them.
In Rails 4.0 when a column or a table is renamed the related indexes are also renamed. If you have migrations which rename the indexes, they are no longer needed.
Rails 4.0 has changed serialized_attributes and attr_readonly to class methods only. You shouldn't use instance methods since it's now deprecated. You should change them to use class methods, e.g. self.serialized_attributes to self.class.serialized_attributes.
When using the default coder, assigning nil to a serialized attribute will save it
to the database as NULL instead of passing the nil value through YAML ("--- \n...\n").
Rails 4.0 has removed attr_accessible and attr_protected feature in favor of Strong Parameters. You can use the
for a smooth upgrade path.
If you are not using Protected Attributes, you can remove any options related to
this gem such as whitelist_attributes or mass_assignment_sanitizer options.
Rails 4.0 requires that scopes use a callable object such as a Proc or lambda:
scope :active, where(active: true)
scope :active, -& { where active: true }
Rails 4.0 has deprecated ActiveRecord::Fixtures in favor of ActiveRecord::FixtureSet.
Rails 4.0 has deprecated ActiveRecord::TestCase in favor of ActiveSupport::TestCase.
Rails 4.0 has deprecated the old-style hash based finder API. This means that
methods which previously accepted "finder options" no longer do.
For example, Book.find(:all, conditions: { name: '1984' }) has been deprecated in favor of Book.where(name: '1984')
All dynamic methods except for find_by_... and find_by_...! are deprecated.
Here's how you can handle the changes:
find_all_by_...
becomes where(...).
find_last_by_...
becomes where(...).last.
scoped_by_...
becomes where(...).
find_or_initialize_by_... becomes find_or_initialize_by(...).
find_or_create_by_...
becomes find_or_create_by(...).
Note that where(...) returns a relation, not an array like the old finders. If you require an Array, use where(...).to_a.
These equivalent methods may not execute the same SQL as the previous implementation.
To re-enable the old finders, you can use the .
Rails 4.0 has changed to default join table for has_and_belongs_to_many relations to strip the common prefix off the second table name. Any existing has_and_belongs_to_many relationship between models with a common prefix must be specified with the join_table option. For example:
CatalogCategory & ActiveRecord::Base
has_and_belongs_to_many :catalog_products, join_table: 'catalog_categories_catalog_products'
CatalogProduct & ActiveRecord::Base
has_and_belongs_to_many :catalog_categories, join_table: 'catalog_categories_catalog_products'
Note that the prefix takes scopes into account as well, so relations between Catalog::Category and Catalog::Product or Catalog::Category and CatalogProduct need to be updated similarly.
5.5 Active ResourceRails 4.0 extracted Active Resource to its own gem. If you still need the feature you can add the
in your Gemfile.5.6 Active Model
Rails 4.0 has changed how errors attach with the ActiveModel::Validations::ConfirmationValidator. Now when confirmation validations fail, the error will be attached to :#{attribute}_confirmation instead of attribute.
Rails 4.0 has changed ActiveModel::Serializers::JSON.include_root_in_json default value to false. Now, Active Model Serializers and Active Record objects have the same default behavior. This means that you can comment or remove the following option in the config/initializers/wrap_parameters.rb file:
# Disable root element in JSON by default.
# ActiveSupport.on_load(:active_record) do
self.include_root_in_json = false
5.7 Action Pack
Rails 4.0 introduces ActiveSupport::KeyGenerator and uses this as a base from which to generate and verify signed cookies (among other things). Existing signed cookies generated with Rails 3.x will be transparently upgraded if you leave your existing secret_token in place and add the new secret_key_base.
# config/initializers/secret_token.rb
Myapp::Application.config.secret_token = 'existing secret token'
Myapp::Application.config.secret_key_base = 'new secret key base'
Please note that you should wait to set secret_key_base until you have 100% of your userbase on Rails 4.x and are reasonably sure you will not need to rollback to Rails 3.x. This is because cookies signed based on the new secret_key_base in Rails 4.x are not backwards compatible with Rails 3.x. You are free to leave your existing secret_token in place, not set the new secret_key_base, and ignore the deprecation warnings until you are reasonably sure that your upgrade is otherwise complete.If you are relying on the ability for external applications or JavaScript to be able to read your Rails app's signed session cookies (or signed cookies in general) you should not set secret_key_base until you have decoupled these concerns.
Rails 4.0 encrypts the contents of cookie-based sessions if secret_key_base has been set. Rails 3.x signed, but did not encrypt, the contents of cookie-based session. Signed cookies are "secure" in that they are verified to have been generated by your app and are tamper-proof. However, the contents can be viewed by end users, and encrypting the contents eliminates this caveat/concern without a significant performance penalty.
Please read
for details on the move to encrypted session cookies.
Rails 4.0 removed the ActionController::Base.asset_path option. Use the assets pipeline feature.
Rails 4.0 has deprecated ActionController::Base.page_cache_extension option. Use ActionController::Base.default_static_extension instead.
Rails 4.0 has removed Action and Page caching from Action Pack. You will need to add the actionpack-action_caching gem in order to use caches_action and the actionpack-page_caching to use caches_pages in your controllers.
Rails 4.0 has removed the XML parameters parser. You will need to add the actionpack-xml_parser gem if you require this feature.
Rails 4.0 changes the default layout lookup set using symbols or procs that return nil. To get the "no layout" behavior, return false instead of nil.
Rails 4.0 changes the default memcached client from memcache-client to dalli. To upgrade, simply add gem 'dalli' to your Gemfile.
Rails 4.0 deprecates the dom_id and dom_class methods in controllers (they are fine in views). You will need to include the ActionView::RecordIdentifier module in controllers requiring this feature.
Rails 4.0 deprecates the :confirm option for the link_to helper. You should
instead rely on a data attribute (e.g. data: { confirm: 'Are you sure?' }).
This deprecation also concerns the helpers based on this one (such as link_to_if
or link_to_unless).
Rails 4.0 changed how assert_generates, assert_recognizes, and assert_routing work. Now all these assertions raise Assertion instead of ActionController::RoutingError.
Rails 4.0 raises an ArgumentError if clashing named routes are defined. This can be triggered by explicitly defined named routes or by the resources method. Here are two examples that clash with routes named example_path:
get 'one' =& 'test#example', as: :example
get 'two' =& 'test#example', as: :example
resources :examples
get 'clashing/:id' =& 'test#example', as: :example
In the first case, you can simply avoid using the same name for multiple
routes. In the second, you can use the only or except options provided by
the resources method to restrict the routes created as detailed in the
Rails 4.0 also changed the way unicode character routes are drawn. Now you can draw unicode character routes directly. If you already draw such routes, you must change them, for example:
get Rack::Utils.escape('こんにちは'), controller: 'welcome', action: 'index'
get 'こんにちは', controller: 'welcome', action: 'index'
Rails 4.0 requires that routes using match must specify the request method. For example:
# Rails 3.x
match '/' =& 'root#index'
match '/' =& 'root#index', via: :get
get '/' =& 'root#index'
Rails 4.0 has removed ActionDispatch::BestStandardsSupport middleware, &!DOCTYPE html& already triggers standards mode per
and ChromeFrame header has been moved to config.action_dispatch.default_headers.
Remember you must also remove any references to the middleware from your application code, for example:
# Raise exception
config.middleware.insert_before(Rack::Lock, ActionDispatch::BestStandardsSupport)
Also check your environment settings for config.action_dispatch.best_standards_support and remove it if present.
In Rails 4.0, precompiling assets no longer automatically copies non-JS/CSS assets from vendor/assets and lib/assets. Rails application and engine developers should put these assets in app/assets or configure config.assets.precompile.
In Rails 4.0, ActionController::UnknownFormat is raised when the action doesn't handle the request format. By default, the exception is handled by responding with 406 Not Acceptable, but you can override that now. In Rails 3, 406 Not Acceptable was always returned. No overrides.
In Rails 4.0, a generic ActionDispatch::ParamsParser::ParseError exception is raised when ParamsParser fails to parse request params. You will want to rescue this exception instead of the low-level MultiJson::DecodeError, for example.
In Rails 4.0, SCRIPT_NAME is properly nested when engines are mounted on an app that's served from a URL prefix. You no longer have to set default_url_options[:script_name] to work around overwritten URL prefixes.
Rails 4.0 deprecated ActionController::Integration in favor of ActionDispatch::Integration.
Rails 4.0 deprecated ActionController::IntegrationTest in favor of ActionDispatch::IntegrationTest.
Rails 4.0 deprecated ActionController::PerformanceTest in favor of ActionDispatch::PerformanceTest.
Rails 4.0 deprecated ActionController::AbstractRequest in favor of ActionDispatch::Request.
Rails 4.0 deprecated ActionController::Request in favor of ActionDispatch::Request.
Rails 4.0 deprecated ActionController::AbstractResponse in favor of ActionDispatch::Response.
Rails 4.0 deprecated ActionController::Response in favor of ActionDispatch::Response.
Rails 4.0 deprecated ActionController::Routing in favor of ActionDispatch::Routing.
5.8 Active SupportRails 4.0 removes the j alias for ERB::Util#json_escape since j is already used for ActionView::Helpers::JavaScriptHelper#escape_javascript.5.9 Helpers Loading OrderThe order in which helpers from more than one directory are loaded has changed in Rails 4.0. Previously, they were gathered and then sorted alphabetically. After upgrading to Rails 4.0, helpers will preserve the order of loaded directories and will be sorted alphabetically only within each directory. Unless you explicitly use the helpers_path parameter, this change will only impact the way of loading helpers from engines. If you rely on the ordering, you should check if correct methods are available after upgrade. If you would like to change the order in which engines are loaded, you can use config.railties_order= method.5.10 Active Record Observer and Action Controller SweeperActiveRecord::Observer and ActionController::Caching::Sweeper have been extracted to the rails-observers gem. You will need to add the rails-observers gem if you require these features.5.11 sprockets-rails
assets:precompile:primary and assets:precompile:all have been removed. Use assets:precompile instead.
The press option should be changed to config.assets.js_compressor like so for instance:
config.assets.js_compressor = :uglifier
5.12 sass-rails
asset-url with two arguments is deprecated. For example: asset-url("rails.png", image) becomes asset-url("rails.png").
6 Upgrading from Rails 3.1 to Rails 3.2If your application is currently on any version of Rails older than 3.1.x, you
should upgrade to Rails 3.1 before attempting an update to Rails 3.2.The following changes are meant for upgrading your application to the latest
3.2.x version of Rails.6.1 GemfileMake the following changes to your Gemfile.
gem 'rails', '3.2.21'
group :assets do
gem 'sass-rails',
'~& 3.2.6'
gem 'coffee-rails', '~& 3.2.2'
gem 'uglifier',
'&= 1.0.3'
6.2 config/environments/development.rbThere are a couple of new configuration settings that you should add to your development environment:
# Raise exception on mass assignment protection for Active Record models
config.active_record.mass_assignment_sanitizer = :strict
# Log the query plan for queries taking more than this (works
# with SQLite, MySQL, and PostgreSQL)
config.active_record.auto_explain_threshold_in_seconds = 0.5
6.3 config/environments/test.rbThe mass_assignment_sanitizer configuration setting should also be added to config/environments/test.rb:
# Raise exception on mass assignment protection for Active Record models
config.active_record.mass_assignment_sanitizer = :strict
6.4 vendor/pluginsRails 3.2 deprecates vendor/plugins and Rails 4.0 will remove them completely. While it's not strictly necessary as part of a Rails 3.2 upgrade, you can start replacing any plugins by extracting them to gems and adding them to your Gemfile. If you choose not to make them gems, you can move them into, say, lib/my_plugin/* and add an appropriate initializer in config/initializers/my_plugin.rb.6.5 Active RecordOption :dependent =& :restrict has been removed from belongs_to. If you want to prevent deleting the object if there are any associated objects, you can set :dependent =& :destroy and return false after checking for existence of association from any of the associated object's destroy callbacks.7 Upgrading from Rails 3.0 to Rails 3.1If your application is currently on any version of Rails older than 3.0.x, you should upgrade to Rails 3.0 before attempting an update to Rails 3.1.The following changes are meant for upgrading your application to Rails 3.1.12, the last 3.1.x version of Rails.7.1 GemfileMake the following changes to your Gemfile.
gem 'rails', '3.1.12'
gem 'mysql2'
# Needed for the new asset pipeline
group :assets do
gem 'sass-rails',
'~& 3.1.7'
gem 'coffee-rails', '~& 3.1.1'
gem 'uglifier',
'&= 1.0.3'
# jQuery is the default JavaScript library in Rails 3.1
gem 'jquery-rails'
7.2 config/application.rbThe asset pipeline requires the following additions:
config.assets.enabled = true
config.assets.version = '1.0'
If your application is using an "/assets" route for a resource you may want change the prefix used for assets to avoid conflicts:
# Defaults to '/assets'
config.assets.prefix = '/asset-files'
7.3 config/environments/development.rbRemove the RJS setting config.action_view.debug_rjs = true.Add these settings if you enable the asset pipeline:
# Do not compress assets
press = false
# Expands the lines which load the assets
config.assets.debug = true
7.4 config/environments/production.rbAgain, most of the changes below are for the asset pipeline. You can read more about these in the
# Compress JavaScripts and CSS
press = true
# Don't fallback to assets pipeline if a precompiled asset is missed
pile = false
# Generate digests for assets URLs
config.assets.digest = true
# Defaults to Rails.root.join("public/assets")
# config.assets.manifest = YOUR_PATH
# Precompile additional assets (application.js, application.css, and all non-JS/CSS are already added)
# config.assets.precompile += %w( search.js )
# Force all access to the app over SSL, use Strict-Transport-Security, and use secure cookies.
# config.force_ssl = true
7.5 config/environments/test.rbYou can help test performance with these additions to your test environment:
# Configure static asset server for tests with Cache-Control for performance
config.public_file_server.enabled = true
config.public_file_server.headers = {
'Cache-Control' =& 'public, max-age=3600'
7.6 config/initializers/wrap_parameters.rbAdd this file with the following contents, if you wish to wrap parameters into a nested hash. This is on by default in new applications.
# Be sure to restart your server when you modify this file.
# This file contains settings for ActionController::ParamsWrapper which
# is enabled by default.
# Enable parameter wrapping for JSON. You can disable this by setting :format to an empty array.
ActiveSupport.on_load(:action_controller) do
wrap_parameters format: [:json]
# Disable root element in JSON by default.
ActiveSupport.on_load(:active_record) do
self.include_root_in_json = false
7.7 config/initializers/session_store.rbYou need to change your session key to something new, or remove all sessions:
# in config/initializers/session_store.rb
AppName::Application.config.session_store :cookie_store, key: 'SOMETHINGNEW'
$ bin/rake db:sessions:clear
7.8 Remove :cache and :concat options in asset helpers references in views
With the Asset Pipeline the :cache and :concat options aren't used anymore, delete these options from your views.
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