[aws|cloudwatch] Add mocked implementation of put_metric_alarm.

lib/fog/aws/requests/cloud_watch/put_metric_alarm.rb

@@ -56,6 +56,37 @@ module Fog
         end
       end
 
+      class Mock
+        require 'fog/aws/parsers/cloud_watch/put_metric_alarm'
+
+        # See: Fog::AWS::CloudWatch::Real.put_metric_alarm()
+        #
+        def put_metric_alarm(alarm_name, actions, metric)
+          if alarm_name.nil? or alarm_name.empty?
+            raise Fog::Compute::AWS::Error.new("The request must contain the parameter 'alarm_name'")
+          end
+
+          supported_actions = [ "InsufficientData", "OK", "Alarm" ]
+          found_actions = actions.keys.select {|key| supported_actions.include? key }
+          if found_actions.empty?
+            raise Fog::Compute::AWS::Error.new("The request must contain a supported action")
+          end
+
+          metric_requirements = [ "ComparisonOperator", "EvaluationPeriods", "Namespace", "Period", "Statistic", "Threshold" ]
+          metric_requirements.each do |req|
+            unless metric.has_key?(req)
+              raise Fog::Compute::AWS::Error.new("The request must contain a the parameter '%s'" % req)
+            end
+          end
+
+          response = Excon::Response.new
+          response.status = 200
+          response.body = {
+            'requestId' => Fog::AWS::Mock.request_id
+          }
+          response
+        end
+      end
     end
   end
 end