WSO2 CEP + Handle null values

Question

Currently WSO2 CEP is triggered using some Http requests. But some times triggered request has null values. At that time how to handle those null values using CEP.

Answer 1

There two ways of fixing this

1. Using default values in Event Receiver input event mapping https://docs.wso2.com/display/CEP410/Input+Mapping+Types
2. Using Siddhi by checking is null operator with in the query https://docs.wso2.com/display/CEP410/SiddhiQL+Guide+3.0#SiddhiQLGuide3.0-QueryProjection