Iam trying to host a WCF REST service in apigee. I want to cache few master datas-mediocre JSON objects. All i understand from Apigee docs is , i can define Flows and configure policies in my proxy to lookup a cached item and then decide whether to make REST call or not. I specify the variable in my LookUpPolicy. How do i check whether this variable has data or not and then proceed with the REST call? Sorry if its a simple question, i am confused and dont find a simple way to get this done