Use Net::HTTP in a way that handles gzip/deflate compression transparently

http_gzip.rb

require 'addressable/uri'
require 'net/http'
require 'yajl'

# Wikipedia API
url = Addressable::URI.parse 'http://en.wikipedia.org/w/api.php?format=json'

# let Addressable handle query encoding
url.query_values = url.query_values.update :srsearch => 'Scott Pilgrim', :action => 'query', :list => 'search'

response = Net::HTTP.start(url.host, url.port) { |http|
  http.get url.request_uri, 'user-agent' => 'Ruby app <mislav.marohnic@gmail.com>'
  # if Zlib is available, this also sets:
  # Accept-encoding: gzip;q=1.0,deflate;q=0.6,identity;q=0.3
}

# raises an instance of Net::HTTPExceptions exception
response.error! unless Net::HTTPSuccess === response

# response.body is automatically uncompressed
data = Yajl::Parser.parse response.body

results = data['query']['search']