h1. Hydra-Head

Hydra-Head is a Ruby-on-Rails 3 gem containing the core code for a web application using the full stack of hydra building blocks.

See the github wikis for information targeted to developers: "http://github.com/projecthydra/hydra-head/wiki":http://github.com/projecthydra/hydra-head/wiki
See the duraspace hydra wikis for information at the architecture level: "http://wiki.duraspace.org/display/hydra/":http://wiki.duraspace.org/display/hydra/
Additionally, new adopters and potential adopters may find the pages here useful: "http://projecthydra.org/":http://projecthydra.org/

Further questions?  Ask the "hydra-tech list":http://groups.google.com/group/hydra-tech or join the freenode #projecthydra IRC channel.


h2. Installation/Setup

h3. Installation Prerequisites

See "http://github.com/projecthydra/hydra-head/wiki/Installation-Prerequisites":http://github.com/projecthydra/hydra-head/wiki/Installation-Prerequisites

Ruby 1.9.3 is required by Hydra-Head release 4.0; RVM is strongly suggested.

h3. Install Rails, Bundler and Devise

Currently hydra-head is compatible with Rails 3.2

<pre>
gem install 'rails' --version '~>3.2.2'
</pre>
  
h3. Generate a new rails application:

<pre>
rails new my_hydra_head
cd my_hydra_head
</pre>

h3. Install Dependencies

First, add them to the "Gemfile":http://gembundler.com/gemfile.html of your application:

<pre>
  source 'http://rubygems.org'

  gem 'rails', '~>3.2.2'

  gem 'blacklight', '~> 3.3.1'
  gem 'hydra-head', '~> 4.0.0'

  # We will assume that you're using sqlite3 for testing/demo, 
  # but in a production setup you probably want to use a real sql database like mysql or postgres
  gem 'sqlite3'

  # We will assume you're using devise in tutorials/documentation. 
  # You are free to implement your own User/Authentication solution in its place.
  gem 'devise'

  # For testing.  You will probably want to use these to run the tests you write for your hydra head
  group :development, :test do 
         gem 'rspec-rails', '>=2.9.0'
         gem "jettywrapper"
  end # (leave this comment here to catch a stray line inserted by blacklight!)
</pre>

To install all of the dependencies, run:

<pre>
bundle install
</pre>

On some systems, you will have to install system libraries that various gems rely on.  For example, in order to install the curl gem on ubuntu you have to first install libcurl4-openssl-dev and then re-run bundler.

Even if all of the dependencies are satisfied, this will take a _very_ long time the first time you run it.  IF you become impatient, hit Ctl+C then enter this:

<pre>
  gem install blacklight
  gem install hydra-head -v 4.0.0
</pre>

Then re-run bundle install and it will run slightly faster.

h3. Run the generators and migrations:

Run the blacklight generator

<pre>rails g blacklight --devise</pre>

Run the hydra-head generator

<pre>rails g hydra:head -df</pre>

Run the database migrations

<pre>
rake db:migrate
rake db:test:prepare
</pre>

h3. You're done.

Congratulations.  You've set up the code for your Hydra Head.  

Read "Tools for Developing and Testing your Application":http://github.com/projecthydra/hydra-head/wiki/Tools-for-Developing-and-Testing-your-Application, then read "How to Get Started":http://github.com/projecthydra/hydra-head/wiki/How-to-Get-Started to get a sense of what you can do with your Hydra Head.

h2. Modifying and Testing the hydra-head Gem 

For those developers who want to or need to work on the hydra-head gem itself, see the "Instructions for Contributors":http://github.com/projecthydra/hydra-head/wiki/For-Contributors

h2. Acknowledgements

h3. Design & Strategic Contributions

The Hydra Framework would not exist without the extensive design effort undertaken by representatives of repository initiatives from Stanford University, University of Virginia, University of Hull and MediaShelf LLC.  Contributors to that effort include Tom Cramer, Lynn McRae, Martha Sites, Richard Green, Chris Awre, and Matt Zumwalt.  

Thorny Staples from Fedora Commons & DuraSpace deserves special thanks for putting all of these people in the same room together.