feat: support pg

Author: bastos

README.md

@@ -2,7 +2,7 @@
 
 This template is designed for personal use and open-source projects. It provides a quick start for Rails applications with essential features pre-configured, requiring minimal setup.
 
-- **Database**: SQLite3 for simplicity and ease of setup
+- **Database**: Your choice of SQLite (default) or PostgreSQL
 - **Defaults**:
   - Solid Cache for efficient caching
   - Solid Queue for background job processing
@@ -20,6 +20,8 @@ This template is designed for personal use and open-source projects. It provides
 rails new <app_name> -c tailwind -m https://raw.githubusercontent.com/bastos/rails-template/refs/heads/main/template.rb
 ```
 
+During setup, the template will ask if you want to use PostgreSQL instead of the default SQLite database.
+
 ## License
 
 This project is released under the [MIT License](https://opensource.org/licenses/MIT).

template.rb

@@ -3,6 +3,94 @@
 gem "omniauth-rails_csrf_protection"
 gem "letter_opener", group: :development
 
+# Ask the user if they want to use PostgreSQL
+use_postgres = yes?("Use PostgreSQL instead of the default SQLite? (y/N)")
+
+if use_postgres
+  say "Configuring for PostgreSQL...", :green
+
+  # Add pg gem
+  gem 'pg', '~> 1.1' # From Rails 7.1 defaults, adjust if needed
+
+  # Remove sqlite3 gem line (will be added by default if not specified in `rails new`)
+  # This ensures it's removed even if the user didn't use --database=postgresql initially
+  gsub_file 'Gemfile', /^gem\s+["']sqlite3["'].*$/, ''
+
+  # Remove existing database.yml if it exists
+  remove_file 'config/database.yml'
+
+  # Create new database.yml for Postgres using the app_name variable available in the template context
+  create_file 'config/database.yml' do <<~YAML
+    # PostgreSQL. Versions 9.3 and up are supported.
+    #
+    # Install the pg driver:
+    #   gem install pg
+    # On macOS with Homebrew:
+    #   gem install pg -- --with-pg-config=/usr/local/bin/pg_config
+    # On Windows:
+    #   gem install pg
+    #       Choose the win32 build.
+    #       Install PostgreSQL and put its /bin directory on your path.
+    #
+    # Configure Using Gemfile
+    # gem "pg"
+    #
+    default: &default
+      adapter: postgresql
+      encoding: unicode
+      # For details on connection pooling, see Rails configuration guide
+      # https://guides.rubyonrails.org/configuring.html#database-pooling
+      pool: <%= ENV.fetch("RAILS_MAX_THREADS") { 5 } %>
+
+    development:
+      <<: *default
+      database: #{app_name}_development
+      # The specified database role being used to connect to postgres.
+      # To create additional roles in postgres see `$ createuser --help`.
+      # When running `$ rails db:setup`, the development database will be created.
+      # Examples:
+      #
+      #   domain: '/var/run/postgresql'
+      #   host: localhost
+      #   port: 5432
+      #   username: #{app_name}
+      #   password: ''
+
+    test:
+      <<: *default
+      database: #{app_name}_test
+
+    # As with config/credentials.yml, you never want to store sensitive information,
+    # like your database password, in your source code. If your source code is
+    # ever seen by anyone, they now have access to your database.
+    #
+    # Instead, provide the password or database URL as an environment variable when you
+    # deploy your application. For example:
+    #
+    #   DATABASE_URL="postgres://myuser:mypass@localhost/somedatabase"
+    #
+    # If the connection URL is provided in the special DATABASE_URL environment
+    # variable, Rails will automatically merge its configuration values on top of
+    # the values provided in this file. Alternatively, you can specify a connection
+    # URL environment variable explicitly:
+    #
+    #   production:
+    #     url: <%= ENV["MY_APP_DATABASE_URL"] %>
+    #
+    production:
+      <<: *default
+      database: #{app_name}_production
+      username: #{app_name}
+      password: <%= ENV["#{app_name.upcase}_DATABASE_PASSWORD"] %>
+    YAML
+  end
+else
+  # Explicitly add sqlite3 gem if not using Postgres, in case it was removed by mistake or skipped
+  # This makes the default choice more robust.
+  gem 'sqlite3', '~> 1.4'
+  say "Using default SQLite.", :yellow
+end
+
 after_bundle do
   git add: "."