rails-generate

List all available generators

$ rails generate

$ rails generate model [Post] [title:string] [body:text]

$ rails generate controller [Posts] [index] [show] [new] [create]

$ rails generate migration [AddCategoryToPost] [category:string]

$ rails generate scaffold [Post] [title:string] [body:text]

rails generate <GENERATOR> [arguments] [options]

Examples:
rails generate model User name:string email:string
rails generate controller Products index show
rails generate scaffold Post title:string body:text --skip-stylesheets
rails generate migration AddDetailsToProducts description:text part_number:string

--help, -h
    Display help for the specified generator, or list all available generators if no generator is given.

--pretend, -p
    Run in dry-run mode. Shows the files that would be generated without actually creating them.

--force, -f
    Overwrite files that already exist during generation.

--skip, -s
    Skip files that already exist, preventing them from being overwritten.

--quiet, -q
    Suppress status messages during the generation process.

--no-color
    Disable colorized output for generator status messages.

--skip-routes
    Do not add an entry to the application's config/routes.rb file.

--skip-test, --no-test-framework
    Do not generate any test files for the component.

--skip-assets
    Do not generate asset files (e.g., JavaScript or CSS) for the component.

The rails generate command is a fundamental tool in the Ruby on Rails framework, used to automate the creation of various application components. It leverages pre-defined templates and Rails' "convention over configuration" philosophy to generate boilerplate code for models, controllers, views, migrations, scaffolds, mailers, jobs, and more.

By providing the generator name and specific arguments (e.g., model name, controller actions, database fields), rails generate quickly sets up the necessary files and directories, often including associated test files, routes, and database migration files. This drastically reduces the amount of manual setup, ensures consistency, and helps developers adhere to Rails best practices. It's an indispensable command for rapidly building and expanding Rails applications, working in conjunction with rails destroy which serves as its counterpart for removing generated code.

While rails generate is powerful, care must be taken when using the --force option, as it will overwrite existing files without confirmation. Generated code provides a solid starting point but rarely fits all needs perfectly; manual review and customization are always required. Over-reliance without understanding the generated code can sometimes lead to unnecessary boilerplate.

Running rails generate without any arguments will display a comprehensive list of all built-in and custom generators available within the current Rails application, categorized by their type (e.g., Rails, Active Record, Test Unit).

Developers can extend Rails' code generation capabilities by creating their own custom generators. This allows for automation of domain-specific boilerplate code or adherence to unique project standards, further enhancing development workflow efficiency.

The concept of code generation has been integral to Ruby on Rails since its early versions. Initially, generators were invoked via script/generate (pre-Rails 3). With the release of Rails 3, the command was unified under the main rails executable, becoming rails generate. This evolution solidified its role as a core tool for adhering to Rails' "Convention over Configuration" principle, significantly boosting developer productivity by automating repetitive setup tasks and ensuring consistent project structure across applications.

rails destroy, rails new, rails server, rails db:migrate, rails console