added basic json parser support and tests

git-svn-id: https://google-api-ruby-client.googlecode.com/svn/trunk@23 c1d61fac-ed7f-fcc1-18f7-ff78120a04ef

lib/google/api_client/parser/json_parser.rb

@@ -16,8 +16,27 @@ require 'json'
 
 module Google #:nodoc:
   class APIClient #:nodoc:
+
+    ##
+    # Provides a consistent interface by which to parse request and response
+    # content.
+    # TODO(mattpok): ensure floats, URLs, dates are parsed correctly
     class JSONParser
 
+      def generate(hash)
+        # JSON parser used can accept arrays as well, but we will limit
+        # to only allow hash to JSON string parsing to keep a simple interface
+        unless hash.instance_of? Hash
+          raise ArgumentError,
+            "JSON generate expected a Hash but got a #{hash.class}."
+        end
+
+        return JSON.generate hash
+      end
+
+      def parse(json_string)
+        return JSON.parse json_string
+      end
     end
   end
 end

spec/google/api_client/parser/parser_spec.rb

@@ -0,0 +1,39 @@
+# Copyright 2010 Google Inc.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+require 'spec_helper'
+
+require 'json'
+require 'google/api_client/parser/json_parser'
+
+describe Google::APIClient::JSONParser, 'generates json from hash' do
+  before do
+    @parser = Google::APIClient::JSONParser.new
+  end
+
+  it 'should translate simple hash to JSON string' do
+    @parser.generate('test' => 23).should == "{\"test\":23}"
+  end
+end
+
+describe Google::APIClient::JSONParser, 'parses json string into hash' do
+  before do
+    @parser = Google::APIClient::JSONParser.new
+  end
+
+  it 'should parse simple json string into hash' do
+    @parser.parse('{"test":23}').should == {'test' => 23}
+  end
+end
+