Add settings.protocol_binding attribute with tests. Allows setting of ProtocolBinding attribute in AuthnRequest root node of xml doc.

Author: Dan Woolley

test/request_test.rb

@@ -63,6 +63,23 @@ class RequestTest < Test::Unit::TestCase
       assert_match /<samlp:AuthnRequest[^<]* IsPassive='true'/, inflated
     end
 
+    should "create the SAMLRequest URL parameter with ProtocolBinding" do
+      settings = Onelogin::Saml::Settings.new
+      settings.idp_sso_target_url = "http://example.com"
+      settings.protocol_binding = 'urn:oasis:names:tc:SAML:2.0:bindings:HTTP-POST'
+      auth_url = Onelogin::Saml::Authrequest.new.create(settings)
+      assert auth_url =~ /^http:\/\/example\.com\?SAMLRequest=/
+      payload  = CGI.unescape(auth_url.split("=").last)
+      decoded  = Base64.decode64(payload)
+
+      zstream  = Zlib::Inflate.new(-Zlib::MAX_WBITS)
+      inflated = zstream.inflate(decoded)
+      zstream.finish
+      zstream.close
+
+      assert_match /<samlp:AuthnRequest[^<]* ProtocolBinding='urn:oasis:names:tc:SAML:2.0:bindings:HTTP-POST'/, inflated
+    end
+
     should "accept extra parameters" do
       settings = OneLogin::RubySaml::Settings.new
       settings.idp_sso_target_url = "http://example.com"