ginsu

h1. Ginsu

Rails applications are not always born as Rails applications. Sometimes graphic designers create web designs using tools like Dreamweaver and then pass them off to software developers for implementation as web applications

But Rails has a different model for a web site than a tool like BBEdit. Rails thinks in terms of routes that lead to actions that render from templates that can use layouts, but Rapidweaver thinks in terms of pages. Every page includes the whole layout.

Ginsu manages the transition of a web project, from a static web site to the final implementation as a Rails application. Ginsu creates hybrid web sites with some sections served as static content and some sections powered by dynamic Rails actions.

h2. The Problem

You work in a high-volume web shop. Your job is the nerd stuff: programming the dynamic parts of web projects and dealing with site implementation and hosting. A producer gives you a .zip file and tells you that the deadline to get the site hosted is that afternoon. The .zip file contains static .html, .css, image and Flash files from a Dreamweaver project that a graphic designer developed. Then, the punchline: "Only pages X and Y need to be dynamic, leave the rest static. We're still designing it. Oh and we'll be updating this part of page X and this part of page Y once a week."

You don't want to work with a graphic designer every week to update your .erb or .haml files because that makes updates very expensive, which is not very agile. You don't want to configure your web server to serve only a few routes from your Rails app because making changes is hard and so that's also not very agile. You can't implement a CMS back-end for making it all irrelevant because you work in a high-volume shop and you only have an hour.

You need a way to bring your graphic designer into the agile process, so that you and the designer can both make updates to your respective areas of the project.

h2. The Solution

cd yourapp
mkdir static

Copy your static web site from your graphic designer into your Rails application's new "static" directory. If your static web site has a root index file called "index.html", then your Rails app should have a file called "static/index.html".

Configure Ginsu to slice sections of pages from the static web site into partial templates in your Rails application by adding slicing instructions to your config/initializers/ginsu.rb:

# Create a 'header' partial by plucking header HTML from static/index.html using a CSS selector.
ginsu.partials << { :css => 'h3.r a.l', :static => 'index.html', :partial => 'header' }

# Create a 'header' partial by plucking header HTML from static/index.html using an xpath selector.
ginsu.partials << { partial :xpath => '//h3/a[@class="l"]', :static => 'index.html', :partial => 'header' }

# Just use the 'search' parameter to use either CSS or xpath.
ginsu.partials << { :search => 'h3.r a.l', :static => 'index.html', :partial => 'header' }
ginsu.partials << { :search => '//h3/a[@class="m"]', :static => 'index.html', :partial => 'header' }

# Create symbolic links in the public/ directory of the Rails app for selected sections and files.
ginsu.links << { :static => 'galleries' }
ginsu.links << { :static => 'events' }
ginsu.links << { :static => 'holdout.html' }

Now when you run:

rake ginsu:slice

...Ginsu will find the header in your static/index.html file and create a partial in app/views/_header.html.erb with the contents of the HTML element that it locates using your CSS or xpath selector.

Using this technique does not require your graphic designer to make any changes to the Dreamweaver project. You don't have to tag the section that you want to slice out, you simply describe where it's located and Ginsu will find it and slice it out. You bring your graphic designers into the agile process by enabling them to update parts of the web site with their tools, without learning Rails.

h2. Installation

Install the Ginsu gem in your Rails application with:

script/plugin install git://github.com/endymion/ginsu.git

Generate your initializer, for configuring Ginsu:

script/generate ginsu

h2. Configure

The Ginsu configuration is in the initializer file config/initializers/ginsu.rb:

require 'ginsu'
Ginsu::Knife.configure do |ginsu|

	# The default location of the static web site is 'site', but maybe your static
	# site includes 150 MB worth of Photoshop .psd files and you don't want those
	# in your Capistrano deployments.  Change the source path here if you want.
	ginsu.source = '/home/webproject/site'

	ginsu.partials << { :search => '#header', :static => 'index.html', :partial => 'header' }
	ginsu.partials << { :search => '#footer', :static => 'index.html', :partial => 'footer' }

	ginsu.links << { :static => 'galleries' }
	ginsu.links << { :static => 'news' }

end

h2. Features

h3. partial

A partial is the content of an HTML element that Ginsu will partial out of a static HTML document and drop into a Rails partial template.

h3. link

A link is a page or a folder that you want to be entirely served as static content. Ginsu will create symbolic links in your Rails application's public/ directory for each link.