12 files changed, 52 insertions, 41 deletions
diff --git a/guides/source/2_3_release_notes.md b/guides/source/2_3_release_notes.md
index 6976848e95..3f5a3c7ade 100644
--- a/guides/source/2_3_release_notes.md
+++ b/guides/source/2_3_release_notes.md
@@ -10,7 +10,7 @@ Rails 2.3 delivers a variety of new and improved features, including pervasive R
 Application Architecture
 ------------------------
 
-There are two major changes in the architecture of Rails applications: complete integration of the [Rack](http://rack.github.io/) modular web server interface, and renewed support for Rails Engines.
+There are two major changes in the architecture of Rails applications: complete integration of the [Rack](https://rack.github.io/) modular web server interface, and renewed support for Rails Engines.
 
 ### Rack Integration
 
diff --git a/guides/source/5_0_release_notes.md b/guides/source/5_0_release_notes.md
index 5f4be07351..6d53e1c2b4 100644
--- a/guides/source/5_0_release_notes.md
+++ b/guides/source/5_0_release_notes.md
@@ -55,7 +55,7 @@ information.
 ### API Applications
 
 Rails can now be used to create slimmed down API only applications.
-This is useful for creating and serving APIs similar to [Twitter](https://dev.twitter.com) or [GitHub](http://developer.github.com) API, 
+This is useful for creating and serving APIs similar to [Twitter](https://dev.twitter.com) or [GitHub](https://developer.github.com) API, 
 that can be used to serve public facing, as well as, for custom applications.
 
 You can generate a new api Rails app using:
@@ -74,11 +74,11 @@ This will do three main things:
   Controller modules that provide functionalities primarily used by browser
   applications.
 - Configure the generators to skip generating views, helpers and assets when
-  you generate a new resource. 
+  you generate a new resource.
 
-The application provides a base for APIs, 
+The application provides a base for APIs,
 that can then be [configured to pull in functionality](api_app.html) as suitable for the application's needs.  
- 
+
 See the [Using Rails for API-only Applications](api_app.html) guide for more
 information.
 
diff --git a/guides/source/api_app.md b/guides/source/api_app.md
index 64200ec242..5ec79de8a0 100644
--- a/guides/source/api_app.md
+++ b/guides/source/api_app.md
@@ -18,7 +18,7 @@ What is an API Application?
 
 Traditionally, when people said that they used Rails as an "API", they meant
 providing a programmatically accessible API alongside their web application.
-For example, GitHub provides [an API](http://developer.github.com) that you
+For example, GitHub provides [an API](https://developer.github.com) that you
 can use from your own custom clients.
 
 With the advent of client-side frameworks, more developers are using Rails to
@@ -94,7 +94,7 @@ Handled at the Action Pack layer:
   means not having to spend time thinking about how to model your API in terms
   of HTTP.
 - URL Generation: The flip side of routing is URL generation. A good API based
-  on HTTP includes URLs (see [the GitHub Gist API](http://developer.github.com/v3/gists/)
+  on HTTP includes URLs (see [the GitHub Gist API](https://developer.github.com/v3/gists/)
   for an example).
 - Header and Redirection Responses: `head :no_content` and
   `redirect_to user_url(current_user)` come in handy. Sure, you could manually
diff --git a/guides/source/asset_pipeline.md b/guides/source/asset_pipeline.md
index 383e972f74..f148cef24f 100644
--- a/guides/source/asset_pipeline.md
+++ b/guides/source/asset_pipeline.md
@@ -1069,7 +1069,7 @@ Customizing the Pipeline
 ### CSS Compression
 
 One of the options for compressing CSS is YUI. The [YUI CSS
-compressor](http://yui.github.io/yuicompressor/css.html) provides
+compressor](https://yui.github.io/yuicompressor/css.html) provides
 minification.
 
 The following line enables YUI compression, and requires the `yui-compressor`
diff --git a/guides/source/autoloading_and_reloading_constants.md b/guides/source/autoloading_and_reloading_constants.md
index 05743ee4ce..c62194faf4 100644
--- a/guides/source/autoloading_and_reloading_constants.md
+++ b/guides/source/autoloading_and_reloading_constants.md
@@ -475,12 +475,21 @@ it is (edited):
 ```
 $ bin/rails r 'puts ActiveSupport::Dependencies.autoload_paths'
 .../app/assets
+.../app/channels
 .../app/controllers
+.../app/controllers/concerns
 .../app/helpers
+.../app/jobs
 .../app/mailers
 .../app/models
-.../app/controllers/concerns
 .../app/models/concerns
+.../activestorage/app/assets
+.../activestorage/app/controllers
+.../activestorage/app/javascript
+.../activestorage/app/jobs
+.../activestorage/app/models
+.../actioncable/app/assets
+.../actionview/app/assets
 .../test/mailers/previews
 ```
 
diff --git a/guides/source/command_line.md b/guides/source/command_line.md
index 8ae01286e4..2cd8e02a77 100644
--- a/guides/source/command_line.md
+++ b/guides/source/command_line.md
@@ -645,13 +645,16 @@ $ cat config/database.yml
 # Configure Using Gemfile
 # gem 'pg'
 #
-development:
+default: &default
   adapter: postgresql
   encoding: unicode
+  # For details on connection pooling, see Rails configuration guide
+  # http://guides.rubyonrails.org/configuring.html#database-pooling
+  pool: <%= ENV.fetch("RAILS_MAX_THREADS") { 5 } %>
+
+development:
+  <<: *default
   database: gitapp_development
-  pool: 5
-  username: gitapp
-  password:
 ...
 ...
 ```
diff --git a/guides/source/contributing_to_ruby_on_rails.md b/guides/source/contributing_to_ruby_on_rails.md
index 2f2962a3e6..959cd3ea1c 100644
--- a/guides/source/contributing_to_ruby_on_rails.md
+++ b/guides/source/contributing_to_ruby_on_rails.md
@@ -164,7 +164,7 @@ NOTE: The instructions are for Rails > 4. The Redcarpet Gem doesn't work with JR
 Translation efforts we know about (various versions):
 
 * **Italian**: [https://github.com/rixlabs/docrails](https://github.com/rixlabs/docrails)
-* **Spanish**: [http://wiki.github.com/gramos/docrails](http://wiki.github.com/gramos/docrails)
+* **Spanish**: [https://wiki.github.com/gramos/docrails](https://wiki.github.com/gramos/docrails)
 * **Polish**: [https://github.com/apohllo/docrails/tree/master](https://github.com/apohllo/docrails/tree/master)
 * **French** : [https://github.com/railsfrance/docrails](https://github.com/railsfrance/docrails)
 * **Czech** : [https://github.com/rubyonrails-cz/docrails/tree/czech](https://github.com/rubyonrails-cz/docrails/tree/czech)
@@ -324,7 +324,7 @@ file.
 
 #### Testing Active Record
 
-First, create the databases you'll need. You can find a list of the required 
+First, create the databases you'll need. You can find a list of the required
 table names, usernames, and passwords in `activerecord/test/config.example.yml`.
 
 For MySQL and PostgreSQL, running the SQL statements `create database
diff --git a/guides/source/debugging_rails_applications.md b/guides/source/debugging_rails_applications.md
index 7ea3646c30..99bc7c5fb5 100644
--- a/guides/source/debugging_rails_applications.md
+++ b/guides/source/debugging_rails_applications.md
@@ -186,21 +186,17 @@ end
 Here's an example of the log generated when this controller action is executed:
 
 ```
-Processing ArticlesController#create (for 127.0.0.1 at 2008-09-08 11:52:54) [POST]
-  Session ID: BAh7BzoMY3NyZl9pZCIlMDY5MWU1M2I1ZDRjODBlMzkyMWI1OTg2NWQyNzViZjYiCmZsYXNoSUM6J0FjdGl
-vbkNvbnRyb2xsZXI6OkZsYXNoOjpGbGFzaEhhc2h7AAY6CkB1c2VkewA=--b18cd92fba90eacf8137e5f6b3b06c4d724596a4
-  Parameters: {"commit"=>"Create", "article"=>{"title"=>"Debugging Rails",
- "body"=>"I'm learning how to print in logs!!!", "published"=>"0"},
- "authenticity_token"=>"2059c1286e93402e389127b1153204e0d1e275dd", "action"=>"create", "controller"=>"articles"}
-New article: {"updated_at"=>nil, "title"=>"Debugging Rails", "body"=>"I'm learning how to print in logs!!!",
- "published"=>false, "created_at"=>nil}
+Started POST "/articles" for 127.0.0.1 at 2017-08-20 20:53:10 +0900
+Processing by ArticlesController#create as HTML
+  Parameters: {"utf8"=>"✓", "authenticity_token"=>"xhuIbSBFytHCE1agHgvrlKnSVIOGD6jltW2tO+P6a/ACjQ3igjpV4OdbsZjIhC98QizWH9YdKokrqxBCJrtoqQ==", "article"=>{"title"=>"Debugging Rails", "body"=>"I'm learning how to print in logs!!!", "published"=>"0"}, "commit"=>"Create Article"}
+New article: {"id"=>nil, "title"=>"Debugging Rails", "body"=>"I'm learning how to print in logs!!!", "published"=>false, "created_at"=>nil, "updated_at"=>nil}
 Article should be valid: true
-  Article Create (0.000443)   INSERT INTO "articles" ("updated_at", "title", "body", "published",
- "created_at") VALUES('2008-09-08 14:52:54', 'Debugging Rails',
- 'I''m learning how to print in logs!!!', 'f', '2008-09-08 14:52:54')
+   (0.1ms)  BEGIN
+  SQL (0.4ms)  INSERT INTO "articles" ("title", "body", "published", "created_at", "updated_at") VALUES ($1, $2, $3, $4, $5) RETURNING "id"  [["title", "Debugging Rails"], ["body", "I'm learning how to print in logs!!!"], ["published", "f"], ["created_at", "2017-08-20 11:53:10.010435"], ["updated_at", "2017-08-20 11:53:10.010435"]]
+   (0.3ms)  COMMIT
 The article was saved and now the user is going to be redirected...
-Redirected to # Article:0x20af760>
-Completed in 0.01224 (81 reqs/sec) | DB: 0.00044 (3%) | 302 Found [http://localhost/articles]
+Redirected to http://localhost:3000/articles/1
+Completed 302 Found in 4ms (ActiveRecord: 0.8ms)
 ```
 
 Adding extra logging like this makes it easy to search for unexpected or unusual behavior in your logs. If you add extra logging, be sure to make sensible use of log levels to avoid filling your production logs with useless trivia.
diff --git a/guides/source/development_dependencies_install.md b/guides/source/development_dependencies_install.md
index 77b036b20f..5a9729bb0f 100644
--- a/guides/source/development_dependencies_install.md
+++ b/guides/source/development_dependencies_install.md
@@ -30,7 +30,7 @@ Ruby on Rails uses Git for source code control. The [Git homepage](https://git-s
 
 * [Try Git course](https://try.github.io/) is an interactive course that will teach you the basics.
 * The [official Documentation](https://git-scm.com/documentation) is pretty comprehensive and also contains some videos with the basics of Git.
-* [Everyday Git](http://schacon.github.io/git/everyday.html) will teach you just enough about Git to get by.
+* [Everyday Git](https://schacon.github.io/git/everyday.html) will teach you just enough about Git to get by.
 * [GitHub](https://help.github.com/) offers links to a variety of Git resources.
 * [Pro Git](https://git-scm.com/book) is an entire book about Git with a Creative Commons license.
 
@@ -364,7 +364,7 @@ sudo apt-get update && sudo apt-get install yarn
 
 On Fedora or CentOS, just run:
 
-``bash
+```bash
 sudo wget https://dl.yarnpkg.com/rpm/yarn.repo -O /etc/yum.repos.d/yarn.repo
 
 sudo yum install yarn
diff --git a/guides/source/initialization.md b/guides/source/initialization.md
index ccad10f07d..0cfabe2a66 100644
--- a/guides/source/initialization.md
+++ b/guides/source/initialization.md
@@ -99,13 +99,15 @@ configure the load path for your Gemfile's dependencies.
 
 A standard Rails application depends on several gems, specifically:
 
+* actioncable
 * actionmailer
 * actionpack
 * actionview
+* activejob
 * activemodel
 * activerecord
+* activestorage
 * activesupport
-* activejob
 * arel
 * builder
 * bundler
@@ -131,7 +133,7 @@ Once `config/boot.rb` has finished, the next file that is required is
 `ARGV` array simply contains `server` which will be passed over:
 
 ```ruby
-require "rails/command"
+require_relative "command"
 
 aliases = {
   "g"  => "generate",
@@ -170,7 +172,7 @@ module Rails::Command
       namespace = namespace.to_s
       namespace = "help" if namespace.blank? || HELP_MAPPINGS.include?(namespace)
       namespace = "version" if %w( -v --version ).include? namespace
-    
+
       if command = find_by_namespace(namespace)
         command.perform(namespace, args, config)
       else
@@ -189,7 +191,7 @@ module Rails
     class ServerCommand < Base # :nodoc:
       def perform
         set_application_directory!
-  
+
         Rails::Server.new.tap do |server|
           # Require application after server sets environment to propagate
           # the --environment option.
@@ -311,7 +313,7 @@ def parse!(args)
   args, options = args.dup, {}
 
   option_parser(options).parse! args
-  
+
   options[:log_stdout] = options[:daemonize].blank? && (options[:environment] || Rails.env) == "development"
   options[:server]     = args.shift
   options
@@ -366,11 +368,11 @@ private
 
   def log_to_stdout
     wrapped_app # touch the app so the logger is set up
-  
+
     console = ActiveSupport::Logger.new(STDOUT)
     console.formatter = Rails.logger.formatter
     console.level = Rails.logger.level
-  
+
     unless ActiveSupport::Logger.logger_outputs_to?(Rails.logger, STDOUT)
       Rails.logger.extend(ActiveSupport::Logger.broadcast(console))
     end
@@ -537,6 +539,7 @@ require "rails"
   action_mailer/railtie
   active_job/railtie
   action_cable/engine
+  active_storage/engine
   rails/test_unit/railtie
   sprockets/railtie
 ).each do |railtie|
diff --git a/guides/source/rails_on_rack.md b/guides/source/rails_on_rack.md
index cef8450ee4..00020a0ea5 100644
--- a/guides/source/rails_on_rack.md
+++ b/guides/source/rails_on_rack.md
@@ -302,7 +302,7 @@ Resources
 
 ### Learning Rack
 
-* [Official Rack Website](http://rack.github.io)
+* [Official Rack Website](https://rack.github.io)
 * [Introducing Rack](http://chneukirchen.org/blog/archive/2007/02/introducing-rack.html)
 
 ### Understanding Middlewares
diff --git a/guides/source/security.md b/guides/source/security.md
index 56969c7aea..7736a4b224 100644
--- a/guides/source/security.md
+++ b/guides/source/security.md
@@ -1025,7 +1025,7 @@ Here is a list of common headers:
 * **X-Content-Type-Options:** _'nosniff' in Rails by default_ - stops the browser from guessing the MIME type of a file.
 * **X-Content-Security-Policy:** [A powerful mechanism for controlling which sites certain content types can be loaded from](http://w3c.github.io/webappsec/specs/content-security-policy/csp-specification.dev.html)
 * **Access-Control-Allow-Origin:** Used to control which sites are allowed to bypass same origin policies and send cross-origin requests.
-* **Strict-Transport-Security:** [Used to control if the browser is allowed to only access a site over a secure connection](http://en.wikipedia.org/wiki/HTTP_Strict_Transport_Security)
+* **Strict-Transport-Security:** [Used to control if the browser is allowed to only access a site over a secure connection](https://en.wikipedia.org/wiki/HTTP_Strict_Transport_Security)
 
 Environmental Security
 ----------------------
@@ -1060,7 +1060,7 @@ Additional Resources
 
 The security landscape shifts and it is important to keep up to date, because missing a new vulnerability can be catastrophic. You can find additional resources about (Rails) security here:
 
-* Subscribe to the Rails security [mailing list](http://groups.google.com/group/rubyonrails-security).
-* [Brakeman - Rails Security Scanner](http://brakemanscanner.org/) - To perform static security analysis for Rails applications.
+* Subscribe to the Rails security [mailing list](https://groups.google.com/forum/#!forum/rubyonrails-security).
+* [Brakeman - Rails Security Scanner](https://brakemanscanner.org/) - To perform static security analysis for Rails applications.
 * [Keep up to date on the other application layers](http://secunia.com/) (they have a weekly newsletter, too).
 * A [good security blog](https://www.owasp.org) including the [Cross-Site scripting Cheat Sheet](https://www.owasp.org/index.php/DOM_based_XSS_Prevention_Cheat_Sheet).