Introducing the session_migration generator. Creates an add_session_table migration. References #2958.

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@3098 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

6 files changed, 90 insertions, 53 deletions

diff --git a/railties/CHANGELOG b/railties/CHANGELOG
index 2db221f579..96f423f1bb 100644
--- a/railties/CHANGELOG
+++ b/railties/CHANGELOG
@@ -1,5 +1,7 @@
 *SVN*
 
+* Introducing the session_migration generator.  Creates an add_session_table migration.  #2958 [Rick Olson]
+
 * Update to Prototype 1.4.0_rc4. Closes #2943 (old Array.prototype.reverse behavior can be obtained by passing false as an argument). [Sam Stephenson]
 
 * script/console uses RAILS_ENV environment variable if present.  #2932 [Blair Zajac <blair@orcaware.com>
diff --git a/railties/lib/rails_generator/commands.rb b/railties/lib/rails_generator/commands.rb
index 2038bb5fec..97b23fbf5e 100644
--- a/railties/lib/rails_generator/commands.rb
+++ b/railties/lib/rails_generator/commands.rb
@@ -55,6 +55,30 @@ module Rails
         def readme(*args)
         end
 
+        protected
+          def existing_migrations(file_name)
+            Dir.glob("db/migrate/[0-9]*_#{file_name}.rb")
+          end
+
+          def migration_exists?(file_name)
+            not existing_migrations(file_name).empty?
+          end
+
+          def current_migration_number
+            Dir.glob('db/migrate/[0-9]*.rb').inject(0) do |max, file_path|
+              n = File.basename(file_path).split('_', 2).first.to_i
+              if n > max then n else max end
+            end
+          end
+
+          def next_migration_number
+            current_migration_number + 1
+          end
+
+          def next_migration_string(padding = 3)
+            "%.#{padding}d" % next_migration_number
+          end
+
         private
           # Ask the user interactively whether to force collision.
           def force_file_collision?(destination)
@@ -84,10 +108,10 @@ module Rails
             begin_mark = template_part_mark(template_options[:begin_mark], template_options[:mark_id])
             end_mark = template_part_mark(template_options[:end_mark], template_options[:mark_id])
             begin_mark + rendered_part + end_mark
-         end
+          end
 
-         def template_part_mark(name, id)
-           "<!--[#{name}:#{id}]-->\n"
+          def template_part_mark(name, id)
+            "<!--[#{name}:#{id}]-->\n"
           end
       end
 
@@ -279,6 +303,12 @@ module Rails
           end
         end
 
+        # When creating a migration, it knows to find the first available file in db/migrate and use the migration.rb template.
+        def migration_template(relative_source, relative_destination, template_options = {})
+          raise "Another migration is already named #{file_name}: #{existing_migrations(file_name).first}" if migration_exists?(file_name)
+          template(relative_source, "#{relative_destination}/#{next_migration_string}_#{file_name}.rb", template_options)
+        end
+
         private
           # Raise a usage error with an informative WordNet suggestion.
           # Thanks to Florian Gross (flgr).
@@ -385,6 +415,14 @@ end_message
         def complex_template(*args)
           # nothing should be done here
         end
+
+        # When deleting a migration, it knows to delete every file named "[0-9]*_#{file_name}".
+        def migration_template(relative_source, relative_destination, template_options = {})
+          raise "There is no migration named #{file_name}" unless migration_exists?(file_name)
+          existing_migrations(file_name).each do |file_path|
+            file(relative_source, file_path, template_options)
+          end
+        end
       end
 
 
@@ -417,6 +455,10 @@ end_message
         def readme(*args)
           logger.readme args.join(', ')
         end
+        
+        def migration_template(relative_source, relative_destination, options = {})
+          logger.migration_template file_name
+        end
       end
 
       # Update generator's action manifest.
diff --git a/railties/lib/rails_generator/generators/components/migration/migration_generator.rb b/railties/lib/rails_generator/generators/components/migration/migration_generator.rb
index 09674261da..95652139f9 100644
--- a/railties/lib/rails_generator/generators/components/migration/migration_generator.rb
+++ b/railties/lib/rails_generator/generators/components/migration/migration_generator.rb
@@ -5,54 +5,4 @@ class MigrationGenerator < Rails::Generator::NamedBase
       m.migration_template 'migration.rb', 'db/migrate'
     end
   end
-
-  protected
-    def existing_migrations(file_name)
-      Dir.glob("db/migrate/[0-9]*_#{file_name}.rb")
-    end
-
-    def migration_exists?(file_name)
-      not existing_migrations(file_name).empty?
-    end
-
-    def current_migration_number
-      Dir.glob('db/migrate/[0-9]*.rb').inject(0) do |max, file_path|
-        n = File.basename(file_path).split('_', 2).first.to_i
-        if n > max then n else max end
-      end
-    end
-
-    def next_migration_number
-      current_migration_number + 1
-    end
-
-    def next_migration_string(padding = 3)
-      "%.#{padding}d" % next_migration_number
-    end
-end
-
-module Rails::Generator::Commands
-  # When creating, it knows to find the first available file in db/migrate and use the migration.rb template.
-  class Create
-    def migration_template(relative_source, relative_destination, template_options = {})
-      raise "Another migration is already named #{file_name}: #{existing_migrations(file_name).first}" if migration_exists?(file_name)
-      template(relative_source, "#{relative_destination}/#{next_migration_string}_#{file_name}.rb", template_options)
-    end
-  end
-
-  # When deleting, it knows to delete every file named "[0-9]*_#{file_name}".
-  class Destroy
-    def migration_template(relative_source, relative_destination, template_options = {})
-      raise "There is no migration named #{file_name}" unless migration_exists?(file_name)
-      existing_migrations(file_name).each do |file_path|
-        file(relative_source, file_path, template_options)
-      end
-    end
-  end
-
-  class List
-    def migration_template(relative_source, relative_destination, options = {})
-      logger.migration_template file_name
-    end
-  end
 end
diff --git a/railties/lib/rails_generator/generators/components/session_migration/USAGE b/railties/lib/rails_generator/generators/components/session_migration/USAGE
new file mode 100644
index 0000000000..43e4e54c97
--- /dev/null
+++ b/railties/lib/rails_generator/generators/components/session_migration/USAGE
@@ -0,0 +1,15 @@
+Description:
+    The session table migration generator creates a migration for adding a session table 
+    used by CGI::Session::ActiveRecordStore.
+
+    The generator takes a migration name as its argument.  The migration name may be
+    given in CamelCase or under_score.
+
+    The generator creates a migration class in db/migrate prefixed by its number
+    in the queue.
+
+Example:
+    ./script/generate session_migration AddSessionTable
+
+    With 4 existing migrations, this will create an AddSessionTable migration in the
+    file db/migrate/5_add_session_table.rb
\ No newline at end of file
diff --git a/railties/lib/rails_generator/generators/components/session_migration/session_migration_generator.rb b/railties/lib/rails_generator/generators/components/session_migration/session_migration_generator.rb
new file mode 100644
index 0000000000..12802858f6
--- /dev/null
+++ b/railties/lib/rails_generator/generators/components/session_migration/session_migration_generator.rb
@@ -0,0 +1,13 @@
+class SessionMigrationGenerator < Rails::Generator::NamedBase
+  def initialize(runtime_args, runtime_options = {})
+    runtime_args << 'add_session_table' if runtime_args.empty?
+    super
+  end
+
+  def manifest
+    record do |m|
+      m.directory 'db/migrate'
+      m.migration_template 'migration.rb', 'db/migrate'
+    end
+  end
+end
diff --git a/railties/lib/rails_generator/generators/components/session_migration/templates/migration.rb b/railties/lib/rails_generator/generators/components/session_migration/templates/migration.rb
new file mode 100644
index 0000000000..0ab7fcb1e9
--- /dev/null
+++ b/railties/lib/rails_generator/generators/components/session_migration/templates/migration.rb
@@ -0,0 +1,15 @@
+class <%= class_name %> < ActiveRecord::Migration
+  def self.up
+    create_table :sessions do |t|
+      t.column :session_id, :string
+      t.column :data, :text
+      t.column :updated_at, :datetime
+    end
+    
+    add_index :sessions, :session_id
+  end
+
+  def self.down
+    drop_table :sessions
+  end
+end