Checkout of Instiki Trunk 1/21/2007.

vendor/rails/actionpack/lib/action_controller/scaffolding.rb

@@ -0,0 +1,190 @@
+module ActionController
+  module Scaffolding # :nodoc:
+    def self.append_features(base)
+      super
+      base.extend(ClassMethods)
+    end
+
+    # Scaffolding is a way to quickly put an Active Record class online by providing a series of standardized actions
+    # for listing, showing, creating, updating, and destroying objects of the class. These standardized actions come
+    # with both controller logic and default templates that through introspection already know which fields to display
+    # and which input types to use. Example:
+    #
+    #  class WeblogController < ActionController::Base
+    #    scaffold :entry
+    #  end
+    #
+    # This tiny piece of code will add all of the following methods to the controller:
+    #
+    #  class WeblogController < ActionController::Base
+    #    verify :method => :post, :only => [ :destroy, :create, :update ],
+    #           :redirect_to => { :action => :list }
+    #
+    #    def index
+    #      list
+    #    end
+    #
+    #    def list
+    #      @entries = Entry.find_all
+    #      render_scaffold "list"
+    #    end
+    #  
+    #    def show
+    #      @entry = Entry.find(params[:id])
+    #      render_scaffold
+    #    end
+    #    
+    #    def destroy
+    #      Entry.find(params[:id]).destroy
+    #      redirect_to :action => "list"
+    #    end
+    #    
+    #    def new
+    #      @entry = Entry.new
+    #      render_scaffold
+    #    end
+    #    
+    #    def create
+    #      @entry = Entry.new(params[:entry])
+    #      if @entry.save
+    #        flash[:notice] = "Entry was successfully created"
+    #        redirect_to :action => "list"
+    #      else
+    #        render_scaffold('new')
+    #      end
+    #    end
+    #    
+    #    def edit
+    #      @entry = Entry.find(params[:id])
+    #      render_scaffold
+    #    end
+    #    
+    #    def update
+    #      @entry = Entry.find(params[:id])
+    #      @entry.attributes = params[:entry]
+    #  
+    #      if @entry.save
+    #        flash[:notice] = "Entry was successfully updated"
+    #        redirect_to :action => "show", :id => @entry
+    #      else
+    #        render_scaffold('edit')
+    #      end
+    #    end
+    #  end
+    #
+    # The <tt>render_scaffold</tt> method will first check to see if you've made your own template (like "weblog/show.rhtml" for 
+    # the show action) and if not, then render the generic template for that action. This gives you the possibility of using the 
+    # scaffold while you're building your specific application. Start out with a totally generic setup, then replace one template 
+    # and one action at a time while relying on the rest of the scaffolded templates and actions.
+    module ClassMethods
+      # Adds a swath of generic CRUD actions to the controller. The +model_id+ is automatically converted into a class name unless
+      # one is specifically provide through <tt>options[:class_name]</tt>. So <tt>scaffold :post</tt> would use Post as the class
+      # and @post/@posts for the instance variables.
+      # 
+      # It's possible to use more than one scaffold in a single controller by specifying <tt>options[:suffix] = true</tt>. This will
+      # make <tt>scaffold :post, :suffix => true</tt> use method names like list_post, show_post, and create_post 
+      # instead of just list, show, and post. If suffix is used, then no index method is added.
+      def scaffold(model_id, options = {})
+        options.assert_valid_keys(:class_name, :suffix)
+
+        singular_name = model_id.to_s
+        class_name    = options[:class_name] || singular_name.camelize
+        plural_name   = singular_name.pluralize
+        suffix        = options[:suffix] ? "_#{singular_name}" : ""
+
+        unless options[:suffix]
+          module_eval <<-"end_eval", __FILE__, __LINE__
+            def index
+              list
+            end
+          end_eval
+        end
+        
+        module_eval <<-"end_eval", __FILE__, __LINE__
+          
+          verify :method => :post, :only => [ :destroy#{suffix}, :create#{suffix}, :update#{suffix} ],
+                 :redirect_to => { :action => :list#{suffix} }
+          
+        
+          def list#{suffix}
+            @#{singular_name}_pages, @#{plural_name} = paginate :#{plural_name}, :per_page => 10
+            render#{suffix}_scaffold "list#{suffix}"
+          end
+
+          def show#{suffix}
+            @#{singular_name} = #{class_name}.find(params[:id])
+            render#{suffix}_scaffold
+          end
+          
+          def destroy#{suffix}
+            #{class_name}.find(params[:id]).destroy
+            redirect_to :action => "list#{suffix}"
+          end
+          
+          def new#{suffix}
+            @#{singular_name} = #{class_name}.new
+            render#{suffix}_scaffold
+          end
+          
+          def create#{suffix}
+            @#{singular_name} = #{class_name}.new(params[:#{singular_name}])
+            if @#{singular_name}.save
+              flash[:notice] = "#{class_name} was successfully created"
+              redirect_to :action => "list#{suffix}"
+            else
+              render#{suffix}_scaffold('new')
+            end
+          end
+          
+          def edit#{suffix}
+            @#{singular_name} = #{class_name}.find(params[:id])
+            render#{suffix}_scaffold
+          end
+          
+          def update#{suffix}
+            @#{singular_name} = #{class_name}.find(params[:id])
+            @#{singular_name}.attributes = params[:#{singular_name}]
+
+            if @#{singular_name}.save
+              flash[:notice] = "#{class_name} was successfully updated"
+              redirect_to :action => "show#{suffix}", :id => @#{singular_name}
+            else
+              render#{suffix}_scaffold('edit')
+            end
+          end
+          
+          private
+            def render#{suffix}_scaffold(action=nil)
+              action ||= caller_method_name(caller)
+              # logger.info ("testing template:" + "\#{self.class.controller_path}/\#{action}") if logger
+              
+              if template_exists?("\#{self.class.controller_path}/\#{action}")
+                render_action(action)
+              else
+                @scaffold_class = #{class_name}
+                @scaffold_singular_name, @scaffold_plural_name = "#{singular_name}", "#{plural_name}"
+                @scaffold_suffix = "#{suffix}"
+                add_instance_variables_to_assigns
+
+                @template.instance_variable_set("@content_for_layout", @template.render_file(scaffold_path(action.sub(/#{suffix}$/, "")), false))
+
+                if !active_layout.nil?
+                  render_file(active_layout, nil, true)
+                else
+                  render_file(scaffold_path("layout"))
+                end
+              end
+            end
+
+            def scaffold_path(template_name)
+              File.dirname(__FILE__) + "/templates/scaffolds/" + template_name + ".rhtml"
+            end
+            
+            def caller_method_name(caller)
+              caller.first.scan(/`(.*)'/).first.first # ' ruby-mode
+            end
+        end_eval
+      end      
+    end
+  end
+end