【Rails】定義されているRailsコマンドを確認する。

## 定義されているRailsコマンドを確認する
```
$ rails -vT
```
このコマンドを打つと以下のように、定義されているコマンドとその説明が表示される。

```
rails about                              # List versions of all Rails frameworks and the environment
rails action_mailbox:ingress:exim        # Relay an inbound email from Exim to Action Mailbox (URL and INGRESS_PASSWORD required)
rails action_mailbox:ingress:postfix     # Relay an inbound email from Postfix to Action Mailbox (URL and INGRESS_PASSWORD required)
rails action_mailbox:ingress:qmail       # Relay an inbound email from Qmail to Action Mailbox (URL and INGRESS_PASSWORD required)
rails action_mailbox:install             # Copy over the migration
rails action_text:install                # Copy over the migration, stylesheet, and JavaScript files
rails active_storage:install             # Copy over the migration needed to the application
rails app:template                       # Applies the template supplied by LOCATION=(/path/to/template) or URL
rails app:update                         # Update configs and some other initially generated files (or use just update:configs or update:bin)
rails assets:clean[keep]                 # Remove old compiled assets
rails assets:clobber                     # Remove compiled assets
rails assets:environment                 # Load asset compile environment
rails assets:precompile                  # Compile all the assets named in config.assets.precompile
rails cache_digests:dependencies         # Lookup first-level dependencies for TEMPLATE (like messages/show or comments/_comment.html)
rails cache_digests:nested_dependencies  # Lookup nested dependencies for TEMPLATE (like messages/show or comments/_comment.html)
rails db:create                          # Creates the database from DATABASE_URL or config/database.yml for the current RAILS_ENV (use db:create:all to create all databases in the config). Witho...
rails db:drop                            # Drops the database from DATABASE_URL or config/database.yml for the current RAILS_ENV (use db:drop:all to drop all databases in the config). Without RAI...
rails db:environment:set                 # Set the environment value for the database
rails db:fixtures:load                   # Loads fixtures into the current environment's database
rails db:migrate                         # Migrate the database (options: VERSION=x, VERBOSE=false, SCOPE=blog)
rails db:migrate:status                  # Display status of migrations
rails db:prepare                         # Runs setup if database does not exist, or runs migrations if it does
rails db:rollback                        # Rolls the schema back to the previous version (specify steps w/ STEP=n)
rails db:schema:cache:clear              # Clears a db/schema_cache.yml file
rails db:schema:cache:dump               # Creates a db/schema_cache.yml file
rails db:schema:dump                     # Creates a db/schema.rb file that is portable against any DB supported by Active Record
rails db:schema:load                     # Loads a schema.rb file into the database
rails db:seed                            # Loads the seed data from db/seeds.rb
rails db:seed:replant                    # Truncates tables of each database for current environment and loads the seeds
rails db:setup                           # Creates the database, loads the schema, and initializes with the seed data (use db:reset to also drop the database first)
rails db:structure:dump                  # Dumps the database structure to db/structure.sql
rails db:structure:load                  # Recreates the databases from the structure.sql file
rails db:version                         # Retrieves the current schema version number
rails log:clear                          # Truncates all/specified *.log files in log/ to zero bytes (specify which logs with LOGS=test,development)
rails middleware                         # Prints out your Rack middleware stack
rails ranks:chapter2:update              # chapter2 ゲーム内のユーザーランキング情報を更新する
rails restart                            # Restart app by touching tmp/restart.txt
rails secret                             # Generate a cryptographically secure secret key (this is typically used to generate a secret for cookie sessions)
rails stats                              # Report code statistics (KLOCs, etc) from the application or engine
rails test                               # Runs all tests in test folder except system ones
rails test:db                            # Run tests quickly, but also reset db
rails test:system                        # Run system tests only
rails time:zones[country_or_offset]      # List all time zones, list by two-letter country code (`rails time:zones[US]`), or list by UTC offset (`rails time:zones[-8]`)
rails tmp:clear                          # Clear cache, socket and screenshot files from tmp/ (narrow w/ tmp:cache:clear, tmp:sockets:clear, tmp:screenshots:clear)
rails tmp:create                         # Creates tmp directories for cache, sockets, and pids
rails webpacker                          # Lists all available tasks in Webpacker
rails webpacker:binstubs                 # Installs Webpacker binstubs in this application
rails webpacker:check_binstubs           # Verifies that webpack & webpack-dev-server are present
rails webpacker:check_node               # Verifies if Node.js is installed
rails webpacker:check_yarn               # Verifies if Yarn is installed
rails webpacker:clean[keep]              # Remove old compiled webpacks
rails webpacker:clobber                  # Remove the webpack compiled output directory
rails webpacker:compile                  # Compile JavaScript packs using webpack for production with digests
rails webpacker:info                     # Provide information on Webpacker's environment
rails webpacker:install                  # Install Webpacker in this application
rails webpacker:install:angular          # Install everything needed for Angular
rails webpacker:install:coffee           # Install everything needed for Coffee
rails webpacker:install:elm              # Install everything needed for Elm
rails webpacker:install:erb              # Install everything needed for Erb
rails webpacker:install:react            # Install everything needed for React
rails webpacker:install:stimulus         # Install everything needed for Stimulus
rails webpacker:install:svelte           # Install everything needed for Svelte
rails webpacker:install:typescript       # Install everything needed for Typescript
rails webpacker:install:vue              # Install everything needed for Vue
rails webpacker:verify_install           # Verifies if Webpacker is installed
rails webpacker:yarn_install             # Support for older Rails versions
rails yarn:install                       # Install all JavaScript dependencies as specified via Yarn
rails zeitwerk:check                     # Checks project structure for Zeitwerk compatibility
$ rails -vT
rails about                              # List versions of all Rails frameworks and the environment
rails action_mailbox:ingress:exim        # Relay an inbound email from Exim to Action Mailbox (URL and INGRESS_PASSWORD required)
rails action_mailbox:ingress:postfix     # Relay an inbound email from Postfix to Action Mailbox (URL and INGRESS_PASSWORD required)
rails action_mailbox:ingress:qmail       # Relay an inbound email from Qmail to Action Mailbox (URL and INGRESS_PASSWORD required)
rails action_mailbox:install             # Copy over the migration
rails action_text:install                # Copy over the migration, stylesheet, and JavaScript files
rails active_storage:install             # Copy over the migration needed to the application
rails app:template                       # Applies the template supplied by LOCATION=(/path/to/template) or URL
rails app:update                         # Update configs and some other initially generated files (or use just update:configs or update:bin)
rails assets:clean[keep]                 # Remove old compiled assets
rails assets:clobber                     # Remove compiled assets
rails assets:environment                 # Load asset compile environment
rails assets:precompile                  # Compile all the assets named in config.assets.precompile
rails cache_digests:dependencies         # Lookup first-level dependencies for TEMPLATE (like messages/show or comments/_comment.html)
rails cache_digests:nested_dependencies  # Lookup nested dependencies for TEMPLATE (like messages/show or comments/_comment.html)
rails db:create                          # Creates the database from DATABASE_URL or config/database.yml for the current RAILS_ENV (use db:create:all to create all databases in the config). Witho...
rails db:drop                            # Drops the database from DATABASE_URL or config/database.yml for the current RAILS_ENV (use db:drop:all to drop all databases in the config). Without RAI...
rails db:environment:set                 # Set the environment value for the database
rails db:fixtures:load                   # Loads fixtures into the current environment's database
rails db:migrate                         # Migrate the database (options: VERSION=x, VERBOSE=false, SCOPE=blog)
rails db:migrate:status                  # Display status of migrations
rails db:prepare                         # Runs setup if database does not exist, or runs migrations if it does
rails db:rollback                        # Rolls the schema back to the previous version (specify steps w/ STEP=n)
rails db:schema:cache:clear              # Clears a db/schema_cache.yml file
rails db:schema:cache:dump               # Creates a db/schema_cache.yml file
rails db:schema:dump                     # Creates a db/schema.rb file that is portable against any DB supported by Active Record
rails db:schema:load                     # Loads a schema.rb file into the database
rails db:seed                            # Loads the seed data from db/seeds.rb
rails db:seed:replant                    # Truncates tables of each database for current environment and loads the seeds
rails db:setup                           # Creates the database, loads the schema, and initializes with the seed data (use db:reset to also drop the database first)
rails db:structure:dump                  # Dumps the database structure to db/structure.sql
rails db:structure:load                  # Recreates the databases from the structure.sql file
rails db:version                         # Retrieves the current schema version number
rails log:clear                          # Truncates all/specified *.log files in log/ to zero bytes (specify which logs with LOGS=test,development)
rails middleware                         # Prints out your Rack middleware stack
rails restart                            # Restart app by touching tmp/restart.txt
rails secret                             # Generate a cryptographically secure secret key (this is typically used to generate a secret for cookie sessions)
rails stats                              # Report code statistics (KLOCs, etc) from the application or engine
rails test                               # Runs all tests in test folder except system ones
rails test:db                            # Run tests quickly, but also reset db
rails test:system                        # Run system tests only
rails time:zones[country_or_offset]      # List all time zones, list by two-letter country code (`rails time:zones[US]`), or list by UTC offset (`rails time:zones[-8]`)
rails tmp:clear                          # Clear cache, socket and screenshot files from tmp/ (narrow w/ tmp:cache:clear, tmp:sockets:clear, tmp:screenshots:clear)
rails tmp:create                         # Creates tmp directories for cache, sockets, and pids
rails webpacker                          # Lists all available tasks in Webpacker
rails webpacker:binstubs                 # Installs Webpacker binstubs in this application
rails webpacker:check_binstubs           # Verifies that webpack & webpack-dev-server are present
rails webpacker:check_node               # Verifies if Node.js is installed
rails webpacker:check_yarn               # Verifies if Yarn is installed
rails webpacker:clean[keep]              # Remove old compiled webpacks
rails webpacker:clobber                  # Remove the webpack compiled output directory
rails webpacker:compile                  # Compile JavaScript packs using webpack for production with digests
rails webpacker:info                     # Provide information on Webpacker's environment
rails webpacker:install                  # Install Webpacker in this application
rails webpacker:install:angular          # Install everything needed for Angular
rails webpacker:install:coffee           # Install everything needed for Coffee
rails webpacker:install:elm              # Install everything needed for Elm
rails webpacker:install:erb              # Install everything needed for Erb
rails webpacker:install:react            # Install everything needed for React
rails webpacker:install:stimulus         # Install everything needed for Stimulus
rails webpacker:install:svelte           # Install everything needed for Svelte
rails webpacker:install:typescript       # Install everything needed for Typescript
rails webpacker:install:vue              # Install everything needed for Vue
rails webpacker:verify_install           # Verifies if Webpacker is installed
rails webpacker:yarn_install             # Support for older Rails versions
rails yarn:install                       # Install all JavaScript dependencies as specified via Yarn
rails zeitwerk:check                     # Checks project structure for Zeitwerk compatibility
```

なかなか使える気がしている。