Create a generator for the Version model and its migration

README.md

@@ -18,7 +18,13 @@ Or install it yourself as:
 
     $ gem install active_versioning
 
+Once installed, generate the necessary files and run migrations:
+
+    $ rails generate active_versioning
+    $ bundle exec rake db:migrate
+
 ## Setup
+
 To set up versioning in your Rails app, include the following module in each model you'd like to version:
 ```ruby
 class Post < ActiveRecord::Base
@@ -57,6 +63,7 @@ post.destroy_draft
 ```
 
 ## Working with Versions
+
 A draft is just a version with a particular state.  To access all the versions for a particular record, use...
 ```ruby
 post.versions              # => All versions, whether the version state is 'create', 'draft', or 'commit'
@@ -74,6 +81,7 @@ post.create_draft_from_version(old_version.id)
 This will set `post.current_draft`'s attributes to the attributes stored in the given version's record. Returns boolean based on the save's success.
 
 ## Capturing Version Metadata
+
 In addition to manually committing a version with a committer and commit message...
 ```ruby
 post.current_draft.commit(committer: current_admin.full_name, commit_message: 'Update post title.')

lib/active_versioning.rb

@@ -1,4 +1,5 @@
 require 'active_versioning/version'
+require 'generators/active_versioning_generator'
 
 module ActiveVersioning
   autoload :Model, 'active_versioning/model'

lib/generators/active_versioning_generator.rb

@@ -0,0 +1,15 @@
+require 'rails/generators/active_record/migration'
+
+class ActiveVersioningGenerator < Rails::Generators::Base
+  include ActiveRecord::Generators::Migration
+
+  source_root File.expand_path('../templates', __FILE__)
+
+  def install_models
+    copy_file 'models/version.rb', 'app/models/version.rb'
+  end
+
+  def install_migrations
+    migration_template 'migrations/create_versions.rb', 'db/migrate/create_versions.rb'
+  end
+end

lib/generators/templates/migrations/create_versions.rb

@@ -0,0 +1,18 @@
+class CreateVersions < ActiveRecord::Migration
+  def change
+    create_table :versions do |t|
+      t.string   :versionable_type, null: false
+      t.integer  :versionable_id,   null: false
+      t.string   :event,            null: false
+      t.string   :committer
+      t.text     :object
+      t.boolean  :draft,            default: false
+      t.text     :commit_message
+      t.datetime :committed_at
+
+      t.timestamps null: false
+    end
+
+    add_index :versions, [:versionable_type, :versionable_id]
+  end
+end

lib/generators/templates/models/version.rb

@@ -0,0 +1,3 @@
+class Version < ActiveRecord::Base
+  include ActiveVersioning::Model
+end

spec/lib/generators/active_versioning_generator_spec.rb

@@ -0,0 +1,18 @@
+require 'spec_helper'
+
+RSpec.describe ActiveVersioningGenerator, type: :generator do
+  destination File.expand_path('../../../../tmp', __FILE__)
+
+  before do
+    prepare_destination
+    run_generator
+  end
+
+  it "generates the version model" do
+    assert_file 'app/models/version.rb', /class Version < ActiveRecord::Base/
+  end
+
+  it "generates the versions migration" do
+    assert_migration 'db/migrate/*_create_versions.rb', /class CreateVersions < ActiveRecord::Migration/
+  end
+end