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Diffstat (limited to 'guides')
36 files changed, 654 insertions, 144 deletions
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gem "arel", github: "rails/arel" end require "action_controller/railtie" diff --git a/guides/bug_report_templates/active_job_master.rb b/guides/bug_report_templates/active_job_master.rb index ce480cbb52..c0c67879f3 100644 --- a/guides/bug_report_templates/active_job_master.rb +++ b/guides/bug_report_templates/active_job_master.rb @@ -1,5 +1,7 @@ # frozen_string_literal: true +gem "bundler", "< 1.16" + begin require "bundler/inline" rescue LoadError => e @@ -13,7 +15,6 @@ gemfile(true) do git_source(:github) { |repo| "https://github.com/#{repo}.git" } gem "rails", github: "rails/rails" - gem "arel", github: "rails/arel" end require "active_job" diff --git a/guides/bug_report_templates/active_record_master.rb b/guides/bug_report_templates/active_record_master.rb index 78411e2d57..b1c83a51f6 100644 --- a/guides/bug_report_templates/active_record_master.rb +++ b/guides/bug_report_templates/active_record_master.rb @@ -1,5 +1,7 @@ # frozen_string_literal: true +gem "bundler", "< 1.16" + begin require "bundler/inline" rescue LoadError => e @@ -13,7 +15,6 @@ gemfile(true) do git_source(:github) { |repo| "https://github.com/#{repo}.git" } gem "rails", github: "rails/rails" - gem "arel", github: "rails/arel" gem "sqlite3" end diff --git a/guides/bug_report_templates/active_record_migrations_gem.rb b/guides/bug_report_templates/active_record_migrations_gem.rb index f75b6fd932..9002b8f428 100644 --- a/guides/bug_report_templates/active_record_migrations_gem.rb +++ b/guides/bug_report_templates/active_record_migrations_gem.rb @@ -37,7 +37,7 @@ end class Payment < ActiveRecord::Base end -class ChangeAmountToAddScale < ActiveRecord::Migration[5.0] +class ChangeAmountToAddScale < ActiveRecord::Migration[5.1] def change reversible do |dir| dir.up do diff --git a/guides/bug_report_templates/active_record_migrations_master.rb b/guides/bug_report_templates/active_record_migrations_master.rb index 60416ed42f..0979a42a41 100644 --- a/guides/bug_report_templates/active_record_migrations_master.rb +++ b/guides/bug_report_templates/active_record_migrations_master.rb @@ -1,5 +1,7 @@ # frozen_string_literal: true +gem "bundler", "< 1.16" + begin require "bundler/inline" rescue LoadError => e @@ -13,7 +15,6 @@ gemfile(true) do git_source(:github) { |repo| "https://github.com/#{repo}.git" } gem "rails", github: "rails/rails" - gem "arel", github: "rails/arel" gem "sqlite3" end @@ -37,7 +38,7 @@ end class Payment < ActiveRecord::Base end -class ChangeAmountToAddScale < ActiveRecord::Migration[5.0] +class ChangeAmountToAddScale < ActiveRecord::Migration[5.2] def change reversible do |dir| dir.up do diff --git a/guides/bug_report_templates/benchmark.rb b/guides/bug_report_templates/benchmark.rb index fb51273e3e..520c5e8bab 100644 --- a/guides/bug_report_templates/benchmark.rb +++ b/guides/bug_report_templates/benchmark.rb @@ -1,5 +1,7 @@ # frozen_string_literal: true +gem "bundler", "< 1.16" + begin require "bundler/inline" rescue LoadError => e @@ -13,7 +15,6 @@ gemfile(true) do git_source(:github) { |repo| "https://github.com/#{repo}.git" } gem "rails", github: "rails/rails" - gem "arel", github: "rails/arel" gem "benchmark-ips" end diff --git a/guides/bug_report_templates/generic_master.rb b/guides/bug_report_templates/generic_master.rb index 384c8b1833..f7c9fedf02 100644 --- a/guides/bug_report_templates/generic_master.rb +++ b/guides/bug_report_templates/generic_master.rb @@ -1,5 +1,7 @@ # frozen_string_literal: true +gem "bundler", "< 1.16" + begin require "bundler/inline" rescue LoadError => e @@ -13,7 +15,6 @@ gemfile(true) do git_source(:github) { |repo| "https://github.com/#{repo}.git" } gem "rails", github: "rails/rails" - gem "arel", github: "rails/arel" end require "active_support" diff --git a/guides/rails_guides/levenshtein.rb b/guides/rails_guides/levenshtein.rb index bafa6bfe9d..c48af797fa 100644 --- a/guides/rails_guides/levenshtein.rb +++ b/guides/rails_guides/levenshtein.rb @@ -38,7 +38,7 @@ module RailsGuides d[m] = x end - return x + x end end end diff --git a/guides/source/5_1_release_notes.md b/guides/source/5_1_release_notes.md index 80c9da6446..6b9a950a42 100644 --- a/guides/source/5_1_release_notes.md +++ b/guides/source/5_1_release_notes.md @@ -350,6 +350,10 @@ Please refer to the [Changelog][action-pack] for detailed changes. * Removed deprecated methods related to controller filters. ([Commit](https://github.com/rails/rails/commit/d7be30e8babf5e37a891522869e7b0191b79b757)) + +* Removed deprecated support to `:text` and `:nothing` in `render`. + ([Commit](https://github.com/rails/rails/commit/79a5ea9eadb4d43b62afacedc0706cbe88c54496), + [Commit](https://github.com/rails/rails/commit/57e1c99a280bdc1b324936a690350320a1cd8111)) ### Deprecations diff --git a/guides/source/action_cable_overview.md b/guides/source/action_cable_overview.md index dd16ba3932..1a86b1fcbb 100644 --- a/guides/source/action_cable_overview.md +++ b/guides/source/action_cable_overview.md @@ -1,12 +1,12 @@ Action Cable Overview ===================== -In this guide you will learn how Action Cable works and how to use WebSockets to +In this guide, you will learn how Action Cable works and how to use WebSockets to incorporate real-time features into your Rails application. After reading this guide, you will know: -* What Action Cable is and its integration on backend and frontend +* What Action Cable is and its integration backend and frontend * How to setup Action Cable * How to setup channels * Deployment and Architecture setup for running Action Cable @@ -129,7 +129,7 @@ subscriptions based on an identifier sent by the cable consumer. # app/channels/chat_channel.rb class ChatChannel < ApplicationCable::Channel # Called when the consumer has successfully - # become a subscriber of this channel. + # become a subscriber to this channel. def subscribed end end @@ -225,7 +225,7 @@ A *broadcasting* is a pub/sub link where anything transmitted by a publisher is routed directly to the channel subscribers who are streaming that named broadcasting. Each channel can be streaming zero or more broadcastings. -Broadcastings are purely an online queue and time dependent. If a consumer is +Broadcastings are purely an online queue and time-dependent. If a consumer is not streaming (subscribed to a given channel), they'll not get the broadcast should they connect later. @@ -515,8 +515,8 @@ user. For a user with an ID of 1, the broadcasting name would be The channel has been instructed to stream everything that arrives at `web_notifications:1` directly to the client by invoking the `received` callback. The data passed as argument is the hash sent as the second parameter -to the server-side broadcast call, JSON encoded for the trip across the wire, -and unpacked for the data argument arriving to `received`. +to the server-side broadcast call, JSON encoded for the trip across the wire +and unpacked for the data argument arriving as `received`. ### More Complete Examples @@ -555,8 +555,7 @@ The async adapter is intended for development/testing and should not be used in ##### Redis Adapter -Action Cable contains two Redis adapters: "normal" Redis and Evented Redis. Both -of the adapters require users to provide a URL pointing to the Redis server. +The Redis adapter requires users to provide a URL pointing to the Redis server. Additionally, a `channel_prefix` may be provided to avoid channel name collisions when using the same Redis server for multiple applications. See the [Redis PubSub documentation](https://redis.io/topics/pubsub#database-amp-scoping) for more details. @@ -570,7 +569,7 @@ This may change in the future. [#27214](https://github.com/rails/rails/issues/27 Action Cable will only accept requests from specified origins, which are passed to the server config as an array. The origins can be instances of -strings or regular expressions, against which a check for match will be performed. +strings or regular expressions, against which a check for the match will be performed. ```ruby config.action_cable.allowed_request_origins = ['http://rubyonrails.com', %r{http://ruby.*}] @@ -593,7 +592,7 @@ environment configuration files. ### Other Configurations -The other common option to configure, is the log tags applied to the +The other common option to configure is the log tags applied to the per-connection logger. Here's an example that uses the user account id if available, else "no-account" while tagging: @@ -608,7 +607,7 @@ config.action_cable.log_tags = [ For a full list of all configuration options, see the `ActionCable::Server::Configuration` class. -Also note that your server must provide at least the same number of database +Also, note that your server must provide at least the same number of database connections as you have workers. The default worker pool size is set to 4, so that means you have to make at least that available. You can change that in `config/database.yml` through the `pool` attribute. @@ -669,8 +668,8 @@ authentication. You can see one way of doing that with Devise in this [article]( ## Dependencies Action Cable provides a subscription adapter interface to process its -pubsub internals. By default, asynchronous, inline, PostgreSQL, evented -Redis, and non-evented Redis adapters are included. The default adapter +pubsub internals. By default, asynchronous, inline, PostgreSQL, and Redis +adapters are included. The default adapter in new Rails applications is the asynchronous (`async`) adapter. The Ruby side of things is built on top of [websocket-driver](https://github.com/faye/websocket-driver-ruby), diff --git a/guides/source/action_controller_overview.md b/guides/source/action_controller_overview.md index d53c4dedf9..28f7246197 100644 --- a/guides/source/action_controller_overview.md +++ b/guides/source/action_controller_overview.md @@ -654,8 +654,8 @@ class UsersController < ApplicationController @users = User.all respond_to do |format| format.html # index.html.erb - format.xml { render xml: @users} - format.json { render json: @users} + format.xml { render xml: @users } + format.json { render json: @users } end end end diff --git a/guides/source/action_view_overview.md b/guides/source/action_view_overview.md index 349108c207..c1e02745de 100644 --- a/guides/source/action_view_overview.md +++ b/guides/source/action_view_overview.md @@ -1160,7 +1160,7 @@ Returns a string of option tags for pretty much any time zone in the world. Returns select and option tags for the given object and method, using `time_zone_options_for_select` to generate the list of option tags. ```ruby -time_zone_select( "user", "time_zone") +time_zone_select("user", "time_zone") ``` #### date_field diff --git a/guides/source/active_record_basics.md b/guides/source/active_record_basics.md index 11aefcb05f..069a624984 100644 --- a/guides/source/active_record_basics.md +++ b/guides/source/active_record_basics.md @@ -304,6 +304,17 @@ user = User.find_by(name: 'David') user.destroy ``` +If you'd like to delete several records in bulk, you may use `destroy_all` +method: + +```ruby +# find and delete all users named David +User.where(name: 'David').destroy_all + +# delete all users +User.destroy_all +``` + Validations ----------- diff --git a/guides/source/active_record_callbacks.md b/guides/source/active_record_callbacks.md index 53417f012e..630dafe632 100644 --- a/guides/source/active_record_callbacks.md +++ b/guides/source/active_record_callbacks.md @@ -213,6 +213,7 @@ The following methods trigger callbacks: * `save!` * `save(validate: false)` * `toggle!` +* `touch` * `update_attribute` * `update` * `update!` @@ -245,7 +246,6 @@ Just as with validations, it is also possible to skip callbacks by using the fol * `increment` * `increment_counter` * `toggle` -* `touch` * `update_column` * `update_columns` * `update_all` diff --git a/guides/source/active_support_core_extensions.md b/guides/source/active_support_core_extensions.md index 067a7b7cb6..66d2fbd939 100644 --- a/guides/source/active_support_core_extensions.md +++ b/guides/source/active_support_core_extensions.md @@ -1796,7 +1796,7 @@ NOTE: Defined in `active_support/core_ext/numeric/bytes.rb`. ### Time -Enables the use of time calculations and declarations, like `45.minutes + 2.hours + 4.years`. +Enables the use of time calculations and declarations, like `45.minutes + 2.hours + 4.weeks`. These methods use Time#advance for precise date calculations when using from_now, ago, etc. as well as adding or subtracting their results from a Time object. For example: @@ -1805,13 +1805,15 @@ as well as adding or subtracting their results from a Time object. For example: # equivalent to Time.current.advance(months: 1) 1.month.from_now -# equivalent to Time.current.advance(years: 2) -2.years.from_now +# equivalent to Time.current.advance(weeks: 2) +2.weeks.from_now -# equivalent to Time.current.advance(months: 4, years: 5) -(4.months + 5.years).from_now +# equivalent to Time.current.advance(months: 4, weeks: 5) +(4.months + 5.weeks).from_now ``` +WARNING. For other durations please refer to the time extensions to `Integer`. + NOTE: Defined in `active_support/core_ext/numeric/time.rb`. ### Formatting @@ -1947,6 +1949,28 @@ The method `ordinalize` returns the ordinal string corresponding to the receiver NOTE: Defined in `active_support/core_ext/integer/inflections.rb`. +### Time + +Enables the use of time calculations and declarations, like `4.months + 5.years`. + +These methods use Time#advance for precise date calculations when using from_now, ago, etc. +as well as adding or subtracting their results from a Time object. For example: + +```ruby +# equivalent to Time.current.advance(months: 1) +1.month.from_now + +# equivalent to Time.current.advance(years: 2) +2.years.from_now + +# equivalent to Time.current.advance(months: 4, years: 5) +(4.months + 5.years).from_now +``` + +WARNING. For other durations please refer to the time extensions to `Numeric`. + +NOTE: Defined in `active_support/core_ext/integer/time.rb`. + Extensions to `BigDecimal` -------------------------- ### `to_s` @@ -2946,6 +2970,32 @@ Extensions to `Date` NOTE: All the following methods are defined in `active_support/core_ext/date/calculations.rb`. +```ruby +yesterday +tomorrow +beginning_of_week (at_beginning_of_week) +end_of_week (at_end_of_week) +monday +sunday +weeks_ago +prev_week (last_week) +next_week +months_ago +months_since +beginning_of_month (at_beginning_of_month) +end_of_month (at_end_of_month) +last_month +beginning_of_quarter (at_beginning_of_quarter) +end_of_quarter (at_end_of_quarter) +beginning_of_year (at_beginning_of_year) +end_of_year (at_end_of_year) +years_ago +years_since +last_year +on_weekday? +on_weekend? +``` + INFO: The following calculation methods have edge cases in October 1582, since days 5..14 just do not exist. This guide does not document their behavior around those days for brevity, but it is enough to say that they do what you would expect. That is, `Date.new(1582, 10, 4).tomorrow` returns `Date.new(1582, 10, 15)` and so on. Please check `test/core_ext/date_ext_test.rb` in the Active Support test suite for expected behavior. #### `Date.current` @@ -2956,68 +3006,6 @@ When making Date comparisons using methods which honor the user time zone, make #### Named dates -##### `prev_year`, `next_year` - -In Ruby 1.9 `prev_year` and `next_year` return a date with the same day/month in the last or next year: - -```ruby -d = Date.new(2010, 5, 8) # => Sat, 08 May 2010 -d.prev_year # => Fri, 08 May 2009 -d.next_year # => Sun, 08 May 2011 -``` - -If date is the 29th of February of a leap year, you obtain the 28th: - -```ruby -d = Date.new(2000, 2, 29) # => Tue, 29 Feb 2000 -d.prev_year # => Sun, 28 Feb 1999 -d.next_year # => Wed, 28 Feb 2001 -``` - -`prev_year` is aliased to `last_year`. - -##### `prev_month`, `next_month` - -In Ruby 1.9 `prev_month` and `next_month` return the date with the same day in the last or next month: - -```ruby -d = Date.new(2010, 5, 8) # => Sat, 08 May 2010 -d.prev_month # => Thu, 08 Apr 2010 -d.next_month # => Tue, 08 Jun 2010 -``` - -If such a day does not exist, the last day of the corresponding month is returned: - -```ruby -Date.new(2000, 5, 31).prev_month # => Sun, 30 Apr 2000 -Date.new(2000, 3, 31).prev_month # => Tue, 29 Feb 2000 -Date.new(2000, 5, 31).next_month # => Fri, 30 Jun 2000 -Date.new(2000, 1, 31).next_month # => Tue, 29 Feb 2000 -``` - -`prev_month` is aliased to `last_month`. - -##### `prev_quarter`, `next_quarter` - -Same as `prev_month` and `next_month`. It returns the date with the same day in the previous or next quarter: - -```ruby -t = Time.local(2010, 5, 8) # => Sat, 08 May 2010 -t.prev_quarter # => Mon, 08 Feb 2010 -t.next_quarter # => Sun, 08 Aug 2010 -``` - -If such a day does not exist, the last day of the corresponding month is returned: - -```ruby -Time.local(2000, 7, 31).prev_quarter # => Sun, 30 Apr 2000 -Time.local(2000, 5, 31).prev_quarter # => Tue, 29 Feb 2000 -Time.local(2000, 10, 31).prev_quarter # => Mon, 30 Oct 2000 -Time.local(2000, 11, 31).next_quarter # => Wed, 28 Feb 2001 -``` - -`prev_quarter` is aliased to `last_quarter`. - ##### `beginning_of_week`, `end_of_week` The methods `beginning_of_week` and `end_of_week` return the dates for the @@ -3135,6 +3123,8 @@ Date.new(2012, 2, 29).years_ago(3) # => Sat, 28 Feb 2009 Date.new(2012, 2, 29).years_since(3) # => Sat, 28 Feb 2015 ``` +`last_year` is short-hand for `#years_ago(1)`. + ##### `months_ago`, `months_since` The methods `months_ago` and `months_since` work analogously for months: @@ -3151,6 +3141,8 @@ Date.new(2010, 4, 30).months_ago(2) # => Sun, 28 Feb 2010 Date.new(2009, 12, 31).months_since(2) # => Sun, 28 Feb 2010 ``` +`last_month` is short-hand for `#months_ago(1)`. + ##### `weeks_ago` The method `weeks_ago` works analogously for weeks: @@ -3313,35 +3305,7 @@ WARNING: `DateTime` is not aware of DST rules and so some of these methods have NOTE: All the following methods are defined in `active_support/core_ext/date_time/calculations.rb`. -The class `DateTime` is a subclass of `Date` so by loading `active_support/core_ext/date/calculations.rb` you inherit these methods and their aliases, except that they will always return datetimes: - -```ruby -yesterday -tomorrow -beginning_of_week (at_beginning_of_week) -end_of_week (at_end_of_week) -monday -sunday -weeks_ago -prev_week (last_week) -next_week -months_ago -months_since -beginning_of_month (at_beginning_of_month) -end_of_month (at_end_of_month) -prev_month (last_month) -next_month -beginning_of_quarter (at_beginning_of_quarter) -end_of_quarter (at_end_of_quarter) -beginning_of_year (at_beginning_of_year) -end_of_year (at_end_of_year) -years_ago -years_since -prev_year (last_year) -next_year -on_weekday? -on_weekend? -``` +The class `DateTime` is a subclass of `Date` so by loading `active_support/core_ext/date/calculations.rb` you inherit these methods and their aliases, except that they will always return datetimes. The following methods are reimplemented so you do **not** need to load `active_support/core_ext/date/calculations.rb` for these ones: @@ -3489,8 +3453,6 @@ Extensions to `Time` NOTE: All the following methods are defined in `active_support/core_ext/time/calculations.rb`. -Active Support adds to `Time` many of the methods available for `DateTime`: - ```ruby past? today? @@ -3502,6 +3464,8 @@ change advance ago since (in) +prev_day +next_day beginning_of_day (midnight, at_midnight, at_beginning_of_day) end_of_day beginning_of_hour (at_beginning_of_hour) @@ -3517,15 +3481,17 @@ months_ago months_since beginning_of_month (at_beginning_of_month) end_of_month (at_end_of_month) -prev_month (last_month) +prev_month next_month +last_month beginning_of_quarter (at_beginning_of_quarter) end_of_quarter (at_end_of_quarter) beginning_of_year (at_beginning_of_year) end_of_year (at_end_of_year) years_ago years_since -prev_year (last_year) +prev_year +last_year next_year on_weekday? on_weekend? @@ -3583,6 +3549,74 @@ now.all_year # => Fri, 01 Jan 2010 00:00:00 UTC +00:00..Fri, 31 Dec 2010 23:59:59 UTC +00:00 ``` +#### `prev_day`, `next_day` + +In Ruby 1.9 `prev_day` and `next_day` return the date in the last or next day: + +```ruby +d = Date.new(2010, 5, 8) # => Sat, 08 May 2010 +d.prev_day # => Fri, 07 May 2010 +d.next_day # => Sun, 09 May 2010 +``` + +#### `prev_month`, `next_month` + +In Ruby 1.9 `prev_month` and `next_month` return the date with the same day in the last or next month: + +```ruby +d = Date.new(2010, 5, 8) # => Sat, 08 May 2010 +d.prev_month # => Thu, 08 Apr 2010 +d.next_month # => Tue, 08 Jun 2010 +``` + +If such a day does not exist, the last day of the corresponding month is returned: + +```ruby +Date.new(2000, 5, 31).prev_month # => Sun, 30 Apr 2000 +Date.new(2000, 3, 31).prev_month # => Tue, 29 Feb 2000 +Date.new(2000, 5, 31).next_month # => Fri, 30 Jun 2000 +Date.new(2000, 1, 31).next_month # => Tue, 29 Feb 2000 +``` + +#### `prev_year`, `next_year` + +In Ruby 1.9 `prev_year` and `next_year` return a date with the same day/month in the last or next year: + +```ruby +d = Date.new(2010, 5, 8) # => Sat, 08 May 2010 +d.prev_year # => Fri, 08 May 2009 +d.next_year # => Sun, 08 May 2011 +``` + +If date is the 29th of February of a leap year, you obtain the 28th: + +```ruby +d = Date.new(2000, 2, 29) # => Tue, 29 Feb 2000 +d.prev_year # => Sun, 28 Feb 1999 +d.next_year # => Wed, 28 Feb 2001 +``` + +#### `prev_quarter`, `next_quarter` + +`prev_quarter` and `next_quarter` return the date with the same day in the previous or next quarter: + +```ruby +t = Time.local(2010, 5, 8) # => 2010-05-08 00:00:00 +0300 +t.prev_quarter # => 2010-02-08 00:00:00 +0200 +t.next_quarter # => 2010-08-08 00:00:00 +0300 +``` + +If such a day does not exist, the last day of the corresponding month is returned: + +```ruby +Time.local(2000, 7, 31).prev_quarter # => 2000-04-30 00:00:00 +0300 +Time.local(2000, 5, 31).prev_quarter # => 2000-02-29 00:00:00 +0200 +Time.local(2000, 10, 31).prev_quarter # => 2000-07-31 00:00:00 +0300 +Time.local(2000, 11, 31).next_quarter # => 2001-03-01 00:00:00 +0200 +``` + +`prev_quarter` is aliased to `last_quarter`. + ### Time Constructors Active Support defines `Time.current` to be `Time.zone.now` if there's a user time zone defined, with fallback to `Time.now`: diff --git a/guides/source/active_support_instrumentation.md b/guides/source/active_support_instrumentation.md index 3b31557f41..25f78fd940 100644 --- a/guides/source/active_support_instrumentation.md +++ b/guides/source/active_support_instrumentation.md @@ -197,6 +197,12 @@ INFO. Additional keys may be added by the caller. } ``` +### unpermitted_parameters.action_controller + +| Key | Value | +| ------- | ---------------- | +| `:keys` | Unpermitted keys | + Action View ----------- @@ -337,6 +343,22 @@ Action Mailer } ``` +### process.action_mailer + +| Key | Value | +| ------------- | ------------------------ | +| `:mailer` | Name of the mailer class | +| `:action` | The action | +| `:args` | The arguments | + +```ruby +{ + mailer: "Notification", + action: "welcome_email", + args: [] +} +``` + Active Support -------------- @@ -450,6 +472,45 @@ Active Job | `:adapter` | QueueAdapter object processing the job | | `:job` | Job object | +Action Cable +------------ + +### perform_action.action_cable + +| Key | Value | +| ---------------- | ------------------------- | +| `:channel_class` | Name of the channel class | +| `:action` | The action | +| `:data` | A hash of data | + +### transmit.action_cable + +| Key | Value | +| ---------------- | ------------------------- | +| `:channel_class` | Name of the channel class | +| `:data` | A hash of data | +| `:via` | Via | + +### transmit_subscription_confirmation.action_cable + +| Key | Value | +| ---------------- | ------------------------- | +| `:channel_class` | Name of the channel class | + +### transmit_subscription_rejection.action_cable + +| Key | Value | +| ---------------- | ------------------------- | +| `:channel_class` | Name of the channel class | + +### broadcast.action_cable + +| Key | Value | +| --------------- | -------------------- | +| `:broadcasting` | A named broadcasting | +| `:message` | A hash of message | +| `:coder` | The coder | + Active Storage -------------- diff --git a/guides/source/api_documentation_guidelines.md b/guides/source/api_documentation_guidelines.md index 2c153d3783..10b89433e7 100644 --- a/guides/source/api_documentation_guidelines.md +++ b/guides/source/api_documentation_guidelines.md @@ -16,7 +16,7 @@ RDoc ---- The [Rails API documentation](http://api.rubyonrails.org) is generated with -[RDoc](http://docs.seattlerb.org/rdoc/). To generate it, make sure you are +[RDoc](https://ruby.github.io/rdoc/). To generate it, make sure you are in the rails root directory, run `bundle install` and execute: ```bash @@ -26,9 +26,9 @@ in the rails root directory, run `bundle install` and execute: Resulting HTML files can be found in the ./doc/rdoc directory. Please consult the RDoc documentation for help with the -[markup](http://docs.seattlerb.org/rdoc/RDoc/Markup.html), +[markup](https://ruby.github.io/rdoc/RDoc/Markup.html), and also take into account these [additional -directives](http://docs.seattlerb.org/rdoc/RDoc/Parser/Ruby.html). +directives](https://ruby.github.io/rdoc/RDoc/Parser/Ruby.html). Wording ------- diff --git a/guides/source/autoloading_and_reloading_constants.md b/guides/source/autoloading_and_reloading_constants.md index ede0324a51..dea87a18f8 100644 --- a/guides/source/autoloading_and_reloading_constants.md +++ b/guides/source/autoloading_and_reloading_constants.md @@ -330,11 +330,17 @@ its resolution next. Let's define *parent* to be that qualifying class or module object, that is, `Billing` in the example above. The algorithm for qualified constants goes like this: -1. The constant is looked up in the parent and its ancestors. +1. The constant is looked up in the parent and its ancestors. In Ruby >= 2.5, +`Object` is skipped if present among the ancestors. `Kernel` and `BasicObject` +are still checked though. 2. If the lookup fails, `const_missing` is invoked in the parent. The default implementation of `const_missing` raises `NameError`, but it can be overridden. +INFO. In Ruby < 2.5 `String::Hash` evaluates to `Hash` and the interpreter +issues a warning: "toplevel constant Hash referenced by String::Hash". Starting +with 2.5, `String::Hash` raises `NameError` because `Object` is skipped. + As you see, this algorithm is simpler than the one for relative constants. In particular, the nesting plays no role here, and modules are not special-cased, if neither they nor their ancestors have the constants, `Object` is **not** @@ -1178,6 +1184,8 @@ end #### Qualified References +WARNING. This gotcha is only possible in Ruby < 2.5. + Given ```ruby diff --git a/guides/source/caching_with_rails.md b/guides/source/caching_with_rails.md index 96650b5be9..31bc478015 100644 --- a/guides/source/caching_with_rails.md +++ b/guides/source/caching_with_rails.md @@ -366,9 +366,9 @@ There are some common options used by all cache implementations. These can be pa * `:namespace` - This option can be used to create a namespace within the cache store. It is especially useful if your application shares a cache with other applications. -* `:compress` - This option can be used to indicate that compression should be used in the cache. This can be useful for transferring large cache entries over a slow network. +* `:compress` - Enabled by default. Compresses cache entries so more data can be stored in the same memory footprint, leading to fewer cache evictions and higher hit rates. -* `:compress_threshold` - This option is used in conjunction with the `:compress` option to indicate a threshold under which cache entries should not be compressed. This defaults to 16 kilobytes. +* `:compress_threshold` - Defaults to 1kB. Cache entries larger than this threshold, specified in bytes, are compressed. * `:expires_in` - This option sets an expiration time in seconds for the cache entry when it will be automatically removed from the cache. @@ -444,6 +444,53 @@ The `write` and `fetch` methods on this cache accept two additional options that config.cache_store = :mem_cache_store, "cache-1.example.com", "cache-2.example.com" ``` +### ActiveSupport::Cache::RedisCacheStore + +The Redis cache store takes advantage of Redis support for least-recently-used +and least-frequently-used key eviction when it reaches max memory, allowing it +to behave much like a Memcached cache server. + +Deployment note: Redis doesn't expire keys by default, so take care to use a +dedicated Redis cache server. Don't fill up your persistent-Redis server with +volatile cache data! Read the +[Redis cache server setup guide](https://redis.io/topics/lru-cache) in detail. + +For an all-cache Redis server, set `maxmemory-policy` to an `allkeys` policy. +Redis 4+ support least-frequently-used (`allkeys-lfu`) eviction, an excellent +default choice. Redis 3 and earlier should use `allkeys-lru` for +least-recently-used eviction. + +Set cache read and write timeouts relatively low. Regenerating a cached value +is often faster than waiting more than a second to retrieve it. Both read and +write timeouts default to 1 second, but may be set lower if your network is +consistently low latency. + +Cache reads and writes never raise exceptions. They just return `nil` instead, +behaving as if there was nothing in the cache. To gauge whether your cache is +hitting exceptions, you may provide an `error_handler` to report to an +exception gathering service. It must accept three keyword arguments: `method`, +the cache store method that was originally called; `returning`, the value that +was returned to the user, typically `nil`; and `exception`, the exception that +was rescued. + +Putting it all together, a production Redis cache store may look something +like this: + +```ruby +cache_servers = %w[ "redis://cache-01:6379/0", "redis://cache-02:6379/0", … ], +config.cache_store = :redis_cache_store, url: cache_servers, + + connect_timeout: 30, # Defaults to 20 seconds + read_timeout: 0.2, # Defaults to 1 second + write_timeout: 0.2, # Defaults to 1 second + + error_handler: -> (method:, returning:, exception:) { + # Report errors to Sentry as warnings + Raven.capture_exception exception, level: 'warning", + tags: { method: method, returning: returning } + } +``` + ### ActiveSupport::Cache::NullStore This cache store implementation is meant to be used only in development or test environments and it never stores anything. This can be very useful in development when you have code that interacts directly with `Rails.cache` but caching may interfere with being able to see the results of code changes. With this cache store, all `fetch` and `read` operations will result in a miss. diff --git a/guides/source/command_line.md b/guides/source/command_line.md index 88c559921c..648645af7c 100644 --- a/guides/source/command_line.md +++ b/guides/source/command_line.md @@ -290,7 +290,7 @@ INFO: You can also use the alias "c" to invoke the console: `rails c`. You can specify the environment in which the `console` command should operate. ```bash -$ bin/rails console staging +$ bin/rails console -e staging ``` If you wish to test out some code without changing any data, you can do that by invoking `rails console --sandbox`. diff --git a/guides/source/configuring.md b/guides/source/configuring.md index 7a32607eb7..6e129a5680 100644 --- a/guides/source/configuring.md +++ b/guides/source/configuring.md @@ -973,7 +973,7 @@ By default Rails ships with three environments: "development", "test", and "prod Imagine you have a server which mirrors the production environment but is only used for testing. Such a server is commonly called a "staging server". To define an environment called "staging" for this server, just create a file called `config/environments/staging.rb`. Please use the contents of any existing file in `config/environments` as a starting point and make the necessary changes from there. -That environment is no different than the default ones, start a server with `rails server -e staging`, a console with `rails console staging`, `Rails.env.staging?` works, etc. +That environment is no different than the default ones, start a server with `rails server -e staging`, a console with `rails console -e staging`, `Rails.env.staging?` works, etc. ### Deploy to a subdirectory (relative url root) @@ -1057,7 +1057,7 @@ After loading the framework and any gems in your application, Rails turns to loa NOTE: You can use subfolders to organize your initializers if you like, because Rails will look into the whole file hierarchy from the initializers folder on down. -TIP: If you have any ordering dependency in your initializers, you can control the load order through naming. Initializer files are loaded in alphabetical order by their path. For example, `01_critical.rb` will be loaded before `02_normal.rb`. +TIP: While Rails supports numbering of initializer file names for load ordering purposes, a better technique is to place any code that need to load in a specific order within the same file. This reduces file name churn, makes dependencies more explicit, and can help surface new concepts within your application. Initialization events --------------------- diff --git a/guides/source/documents.yaml b/guides/source/documents.yaml index 59205ee465..126d2e4845 100644 --- a/guides/source/documents.yaml +++ b/guides/source/documents.yaml @@ -159,6 +159,11 @@ url: engines.html description: This guide explains how to write a mountable engine. work_in_progress: true + - + name: Threading and Code Execution in Rails + url: threading_and_code_execution.html + description: This guide describes the considerations needed and tools available when working directly with concurrency in a Rails application. + work_in_progress: true - name: Contributing to Ruby on Rails documents: diff --git a/guides/source/engines.md b/guides/source/engines.md index 9f39832a7e..b226eac347 100644 --- a/guides/source/engines.md +++ b/guides/source/engines.md @@ -1361,7 +1361,7 @@ that only exists for your engine. In this case, the host application doesn't need to require `admin.css` or `admin.js`. Only the gem's admin layout needs these assets. It doesn't make sense for the host app to include `"blorgh/admin.css"` in its stylesheets. In this situation, you should -explicitly define these assets for precompilation. This tells sprockets to add +explicitly define these assets for precompilation. This tells Sprockets to add your engine assets when `bin/rails assets:precompile` is triggered. You can define assets for precompilation in `engine.rb`: @@ -1501,6 +1501,7 @@ To hook into the initialization process of one of the following classes use the | `ActionController::Base` | `action_controller` | | `ActionController::TestCase` | `action_controller_test_case` | | `ActionDispatch::IntegrationTest` | `action_dispatch_integration_test` | +| `ActionDispatch::SystemTestCase` | `action_dispatch_system_test_case` | | `ActionMailer::Base` | `action_mailer` | | `ActionMailer::TestCase` | `action_mailer_test_case` | | `ActionView::Base` | `action_view` | diff --git a/guides/source/i18n.md b/guides/source/i18n.md index 0153f52249..e6aa6181cc 100644 --- a/guides/source/i18n.md +++ b/guides/source/i18n.md @@ -1171,7 +1171,7 @@ Conclusion At this point you should have a good overview about how I18n support in Ruby on Rails works and are ready to start translating your project. -If you want to discuss certain portions or have questions, please sign up to the [rails-i18n mailing list](http://groups.google.com/group/rails-i18n). +If you want to discuss certain portions or have questions, please sign up to the [rails-i18n mailing list](https://groups.google.com/forum/#!forum/rails-i18n). Contributing to Rails I18n @@ -1179,7 +1179,7 @@ Contributing to Rails I18n I18n support in Ruby on Rails was introduced in the release 2.2 and is still evolving. The project follows the good Ruby on Rails development tradition of evolving solutions in gems and real applications first, and only then cherry-picking the best-of-breed of most widely useful features for inclusion in the core. -Thus we encourage everybody to experiment with new ideas and features in gems or other libraries and make them available to the community. (Don't forget to announce your work on our [mailing list](http://groups.google.com/group/rails-i18n)!) +Thus we encourage everybody to experiment with new ideas and features in gems or other libraries and make them available to the community. (Don't forget to announce your work on our [mailing list](https://groups.google.com/forum/#!forum/rails-i18n)!) If you find your own locale (language) missing from our [example translations data](https://github.com/svenfuchs/rails-i18n/tree/master/rails/locale) repository for Ruby on Rails, please [_fork_](https://github.com/guides/fork-a-project-and-submit-your-modifications) the repository, add your data and send a [pull request](https://help.github.com/articles/about-pull-requests/). @@ -1187,7 +1187,7 @@ If you find your own locale (language) missing from our [example translations da Resources --------- -* [Google group: rails-i18n](https://groups.google.com/group/rails-i18n) - The project's mailing list. +* [Google group: rails-i18n](https://groups.google.com/forum/#!forum/rails-i18n) - The project's mailing list. * [GitHub: rails-i18n](https://github.com/svenfuchs/rails-i18n) - Code repository and issue tracker for the rails-i18n project. Most importantly you can find lots of [example translations](https://github.com/svenfuchs/rails-i18n/tree/master/rails/locale) for Rails that should work for your application in most cases. * [GitHub: i18n](https://github.com/svenfuchs/i18n) - Code repository and issue tracker for the i18n gem. diff --git a/guides/source/layouts_and_rendering.md b/guides/source/layouts_and_rendering.md index b9b327252f..4d79b2db89 100644 --- a/guides/source/layouts_and_rendering.md +++ b/guides/source/layouts_and_rendering.md @@ -285,7 +285,7 @@ the response. Using `:plain` or `:html` might be more appropriate most of the time. NOTE: Unless overridden, your response returned from this render option will be -`text/html`, as that is the default content type of Action Dispatch response. +`text/plain`, as that is the default content type of Action Dispatch response. #### Options for `render` @@ -1266,7 +1266,7 @@ You can also pass in arbitrary local variables to any partial you are rendering In this case, the partial will have access to a local variable `title` with the value "Products Page". -TIP: Rails also makes a counter variable available within a partial called by the collection, named after the member of the collection followed by `_counter`. For example, if you're rendering `@products`, within the partial you can refer to `product_counter` to tell you how many times the partial has been rendered. This does not work in conjunction with the `as: :value` option. +TIP: Rails also makes a counter variable available within a partial called by the collection, named after the title of the partial followed by `_counter`. For example, when rendering a collection `@products` the partial `_product.html.erb` can access the variable `product_counter` which indexes the number of times it has been rendered within the enclosing view. You can also specify a second partial to be rendered between instances of the main partial by using the `:spacer_template` option: diff --git a/guides/source/security.md b/guides/source/security.md index cfa777d433..fa90cadcd2 100644 --- a/guides/source/security.md +++ b/guides/source/security.md @@ -192,9 +192,9 @@ rotations going at any one time. For more details on key rotation with encrypted and signed messages as well as the various options the `rotate` method accepts, please refer to the -[MessageEncryptor API](api.rubyonrails.org/classes/ActiveSupport/MessageEncryptor.html) +[MessageEncryptor API](http://api.rubyonrails.org/classes/ActiveSupport/MessageEncryptor.html) and -[MessageVerifier API](api.rubyonrails.org/classes/ActiveSupport/MessageVerifier.html) +[MessageVerifier API](http://api.rubyonrails.org/classes/ActiveSupport/MessageVerifier.html) documentation. ### Replay Attacks for CookieStore Sessions diff --git a/guides/source/testing.md b/guides/source/testing.md index c5b2a694e7..8416fd163d 100644 --- a/guides/source/testing.md +++ b/guides/source/testing.md @@ -671,6 +671,16 @@ class ApplicationSystemTestCase < ActionDispatch::SystemTestCase end ``` +If you want to use a headless browser, you could use Headless Chrome by adding `headless_chrome` in the `:using` argument. + +```ruby +require "test_helper" + +class ApplicationSystemTestCase < ActionDispatch::SystemTestCase + driven_by :selenium, using: :headless_chrome +end +``` + If your Capybara configuration requires more setup than provided by Rails, this additional configuration could be added into the `application_system_test_case.rb` file. diff --git a/guides/source/threading_and_code_execution.md b/guides/source/threading_and_code_execution.md new file mode 100644 index 0000000000..3d3d31b97e --- /dev/null +++ b/guides/source/threading_and_code_execution.md @@ -0,0 +1,324 @@ +**DO NOT READ THIS FILE ON GITHUB, GUIDES ARE PUBLISHED ON http://guides.rubyonrails.org.** + +Threading and Code Execution in Rails +===================================== + +After reading this guide, you will know: + +* What code Rails will automatically execute concurrently +* How to integrate manual concurrency with Rails internals +* How to wrap all application code +* How to affect application reloading + +-------------------------------------------------------------------------------- + +Automatic Concurrency +--------------------- + +Rails automatically allows various operations to be performed at the same time. + +When using a threaded web server, such as the default Puma, multiple HTTP +requests will be served simultaneously, with each request provided its own +controller instance. + +Threaded Active Job adapters, including the built-in Async, will likewise +execute several jobs at the same time. Action Cable channels are managed this +way too. + +These mechanisms all involve multiple threads, each managing work for a unique +instance of some object (controller, job, channel), while sharing the global +process space (such as classes and their configurations, and global variables). +As long as your code doesn't modify any of those shared things, it can mostly +ignore that other threads exist. + +The rest of this guide describes the mechanisms Rails uses to make it "mostly +ignorable", and how extensions and applications with special needs can use them. + +Executor +-------- + +The Rails Executor separates application code from framework code: any time the +framework invokes code you've written in your application, it will be wrapped by +the Executor. + +The Executor consists of two callbacks: `to_run` and `to_complete`. The Run +callback is called before the application code, and the Complete callback is +called after. + +### Default callbacks + +In a default Rails application, the Executor callbacks are used to: + +* track which threads are in safe positions for autoloading and reloading +* enable and disable the Active Record query cache +* return acquired Active Record connections to the pool +* constrain internal cache lifetimes + +Prior to Rails 5.0, some of these were handled by separate Rack middleware +classes (such as `ActiveRecord::ConnectionAdapters::ConnectionManagement`), or +directly wrapping code with methods like +`ActiveRecord::Base.connection_pool.with_connection`. The Executor replaces +these with a single more abstract interface. + +### Wrapping application code + +If you're writing a library or component that will invoke application code, you +should wrap it with a call to the executor: + +```ruby +Rails.application.executor.wrap do + # call application code here +end +``` + +TIP: If you repeatedly invoke application code from a long-running process, you +may want to wrap using the Reloader instead. + +Each thread should be wrapped before it runs application code, so if your +application manually delegates work to other threads, such as via `Thread.new` +or Concurrent Ruby features that use thread pools, you should immediately wrap +the block: + +```ruby +Thread.new do + Rails.application.executor.wrap do + # your code here + end +end +``` + +NOTE: Concurrent Ruby uses a `ThreadPoolExecutor`, which it sometimes configures +with an `executor` option. Despite the name, it is unrelated. + +The Executor is safely re-entrant; if it is already active on the current +thread, `wrap` is a no-op. + +If it's impractical to wrap the application code in a block (for +example, the Rack API makes this problematic), you can also use the `run!` / +`complete!` pair: + +```ruby +Thread.new do + execution_context = Rails.application.executor.run! + # your code here +ensure + execution_context.complete! if execution_context +end +``` + +### Concurrency + +The Executor will put the current thread into `running` mode in the Load +Interlock. This operation will block temporarily if another thread is currently +either autoloading a constant or unloading/reloading the application. + +Reloader +-------- + +Like the Executor, the Reloader also wraps application code. If the Executor is +not already active on the current thread, the Reloader will invoke it for you, +so you only need to call one. This also guarantees that everything the Reloader +does, including all its callback invocations, occurs wrapped inside the +Executor. + +```ruby +Rails.application.reloader.wrap do + # call application code here +end +``` + +The Reloader is only suitable where a long-running framework-level process +repeatedly calls into application code, such as for a web server or job queue. +Rails automatically wraps web requests and Active Job workers, so you'll rarely +need to invoke the Reloader for yourself. Always consider whether the Executor +is a better fit for your use case. + +### Callbacks + +Before entering the wrapped block, the Reloader will check whether the running +application needs to be reloaded -- for example, because a model's source file has +been modified. If it determines a reload is required, it will wait until it's +safe, and then do so, before continuing. When the application is configured to +always reload regardless of whether any changes are detected, the reload is +instead performed at the end of the block. + +The Reloader also provides `to_run` and `to_complete` callbacks; they are +invoked at the same points as those of the Executor, but only when the current +execution has initiated an application reload. When no reload is deemed +necessary, the Reloader will invoke the wrapped block with no other callbacks. + +### Class Unload + +The most significant part of the reloading process is the Class Unload, where +all autoloaded classes are removed, ready to be loaded again. This will occur +immediately before either the Run or Complete callback, depending on the +`reload_classes_only_on_change` setting. + +Often, additional reloading actions need to be performed either just before or +just after the Class Unload, so the Reloader also provides `before_class_unload` +and `after_class_unload` callbacks. + +### Concurrency + +Only long-running "top level" processes should invoke the Reloader, because if +it determines a reload is needed, it will block until all other threads have +completed any Executor invocations. + +If this were to occur in a "child" thread, with a waiting parent inside the +Executor, it would cause an unavoidable deadlock: the reload must occur before +the child thread is executed, but it cannot be safely performed while the parent +thread is mid-execution. Child threads should use the Executor instead. + +Framework Behavior +------------------ + +The Rails framework components use these tools to manage their own concurrency +needs too. + +`ActionDispatch::Executor` and `ActionDispatch::Reloader` are Rack middlewares +that wraps the request with a supplied Executor or Reloader, respectively. They +are automatically included in the default application stack. The Reloader will +ensure any arriving HTTP request is served with a freshly-loaded copy of the +application if any code changes have occurred. + +Active Job also wraps its job executions with the Reloader, loading the latest +code to execute each job as it comes off the queue. + +Action Cable uses the Executor instead: because a Cable connection is linked to +a specific instance of a class, it's not possible to reload for every arriving +websocket message. Only the message handler is wrapped, though; a long-running +Cable connection does not prevent a reload that's triggered by a new incoming +request or job. Instead, Action Cable uses the Reloader's `before_class_unload` +callback to disconnect all its connections. When the client automatically +reconnects, it will be speaking to the new version of the code. + +The above are the entry points to the framework, so they are responsible for +ensuring their respective threads are protected, and deciding whether a reload +is necessary. Other components only need to use the Executor when they spawn +additional threads. + +### Configuration + +The Reloader only checks for file changes when `cache_classes` is false and +`reload_classes_only_on_change` is true (which is the default in the +`development` environment). + +When `cache_classes` is true (in `production`, by default), the Reloader is only +a pass-through to the Executor. + +The Executor always has important work to do, like database connection +management. When `cache_classes` and `eager_load` are both true (`production`), +no autoloading or class reloading will occur, so it does not need the Load +Interlock. If either of those are false (`development`), then the Executor will +use the Load Interlock to ensure constants are only loaded when it is safe. + +Load Interlock +-------------- + +The Load Interlock allows autoloading and reloading to be enabled in a +multi-threaded runtime environment. + +When one thread is performing an autoload by evaluating the class definition +from the appropriate file, it is important no other thread encounters a +reference to the partially-defined constant. + +Similarly, it is only safe to perform an unload/reload when no application code +is in mid-execution: after the reload, the `User` constant, for example, may +point to a different class. Without this rule, a poorly-timed reload would mean +`User.new.class == User`, or even `User == User`, could be false. + +Both of these constraints are addressed by the Load Interlock. It keeps track of +which threads are currently running application code, loading a class, or +unloading autoloaded constants. + +Only one thread may load or unload at a time, and to do either, it must wait +until no other threads are running application code. If a thread is waiting to +perform a load, it doesn't prevent other threads from loading (in fact, they'll +cooperate, and each perform their queued load in turn, before all resuming +running together). + +### `permit_concurrent_loads` + +The Executor automatically acquires a `running` lock for the duration of its +block, and autoload knows when to upgrade to a `load` lock, and switch back to +`running` again afterwards. + +Other blocking operations performed inside the Executor block (which includes +all application code), however, can needlessly retain the `running` lock. If +another thread encounters a constant it must autoload, this can cause a +deadlock. + +For example, assuming `User` is not yet loaded, the following will deadlock: + +```ruby +Rails.application.executor.wrap do + th = Thread.new do + Rails.application.executor.wrap do + User # inner thread waits here; it cannot load + # User while another thread is running + end + end + + th.join # outer thread waits here, holding 'running' lock +end +``` + +To prevent this deadlock, the outer thread can `permit_concurrent_loads`. By +calling this method, the thread guarantees it will not dereference any +possibly-autoloaded constant inside the supplied block. The safest way to meet +that promise is to put it as close as possible to the blocking call: + +```ruby +Rails.application.executor.wrap do + th = Thread.new do + Rails.application.executor.wrap do + User # inner thread can acquire the load lock, + # load User, and continue + end + end + + ActiveSupport::Dependencies.interlock.permit_concurrent_loads do + th.join # outer thread waits here, but has no lock + end +end +``` + +Another example, using Concurrent Ruby: + +```ruby +Rails.application.executor.wrap do + futures = 3.times.collect do |i| + Concurrent::Future.execute do + Rails.application.executor.wrap do + # do work here + end + end + end + + values = ActiveSupport::Dependencies.interlock.permit_concurrent_loads do + futures.collect(&:value) + end +end +``` + + +### ActionDispatch::DebugLocks + +If your application is deadlocking and you think the Load Interlock may be +involved, you can temporarily add the ActionDispatch::DebugLocks middleware to +`config/application.rb`: + +```ruby +config.middleware.insert_before Rack::Sendfile, + ActionDispatch::DebugLocks +``` + +If you then restart the application and re-trigger the deadlock condition, +`/rails/locks` will show a summary of all threads currently known to the +interlock, which lock level they are holding or awaiting, and their current +backtrace. + +Generally a deadlock will be caused by the interlock conflicting with some other +external lock or blocking I/O call. Once you find it, you can wrap it with +`permit_concurrent_loads`. + diff --git a/guides/source/working_with_javascript_in_rails.md b/guides/source/working_with_javascript_in_rails.md index fc9d3d0ce3..86746a5ae0 100644 --- a/guides/source/working_with_javascript_in_rails.md +++ b/guides/source/working_with_javascript_in_rails.md @@ -174,7 +174,7 @@ passing the `:local` option `form_with`. This will generate the following HTML: ```html -<form action="/articles" method="post" data-remote="true"> +<form action="/articles" accept-charset="UTF-8" method="post" data-remote="true"> ... </form> ``` |
