ActiveRDF-SPARQL-Demo, a balloon

def prompt(say)
  print say + " [Hit ENTER] "; gets
end

puts <<END

ActiveRDF is a library that exposes arbitrary RDF data as Ruby objects.
You, as programmer, manipulate Ruby objects (you invoke methods on them),
and in the background ActiveRDF maps these method calls to queries/updates
on the RDF data.

Lets try to access some RDF data published on a SPARQL endpoint.

We will have to install ActiveRDF and the SPARQL Adapter for ActiveRDF.
Additionally the gem_plugin which handles the Adapters.

END

prompt "are you ready for that?"

require 'rubygems'
require 'active_rdf'

puts <<END

To access some RDF data, we have to open a connection to a triple store. 
In this example we will open a connection to a SPARQL endpoint, with this command:

ConnectionPool.add_data_source :type => :sparql, 
:url => "http://m3pe.org:8080/repositories/test-people",
:results => :sparql_xml

END


prompt "commence connecting!"

ConnectionPool.add_data_source :type => :sparql, 
:url => "http://m3pe.org:8080/repositories/test-people",
:results => :sparql_xml


puts <<END

Through ActiveRDF we can access all RDF properties of a person as Ruby attributes:
eyal = RDFS::Resource.new 'http://activerdf.org/test/eyal'
puts eyal.age
puts eyal.eye
puts eyal.class

END


prompt "register test namespace"

Namespace.register :test, 'http://activerdf.org/test/'


prompt "do it?"

eyal = RDFS::Resource.new 'http://activerdf.org/test/eyal'
puts eyal.age
puts eyal.eye
puts eyal.class


puts <<END

We can register the Namespace used in this example, so that we can use 
Namespaces and local names in a very similiar way, as they are used in RDF:

Namespace.register :test, 'http://activerdf.org/test/'

END



puts <<END

after registering the namespace, we now tell the ObjectManager to search for all 
RDFS classes in the triple store, and construct corresponding Ruby classes, 
so that there is no difference between constructing standard Ruby objects, and
Ruby objects, which are completly backed by the triple store:

ObjectManager.construct_classes

END


prompt "construct classes"

ObjectManager.construct_classes


puts "registering armin..."

prompt "create the Person Armin:"

armin = TEST::Person.new('http://armin-haller.com/#me')


puts <<END

We cannot change anything, since SPARQL endpoints have just read-only access

Now lets search for something in the triple store:

Print all the people, and their friends:
all_people = TEST::Person.find_all
all_people.each do |person|
  puts "#{person} has #{person.eye} eyes"
end

END


prompt "print eye color of all People found:"

all_people = TEST::Person.find_all
all_people.each do |person|
  puts "#{person} has #{person.eye} eyes"
end


puts <<END

Find all people aged 27:

almost_thirties = TEST::Person.find_by_age(27)

END


prompt "search for 27 year old Persons:"

almost_thirties = TEST::Person.find_by_age(27)
puts "the following people are almost thirty: #{almost_thirties}"