Identifying Event Patterns Based On Order of Event Arrival¶
This application demonstrates how to detect patterns with Siddhi pattern concept. In the sample we capture a pattern where the temperature of a room increases by 5 degrees within 2 minutes
- Save this sample
Executing the Sample:¶
- Start the Siddhi application by clicking on 'Run'
- If the Siddhi application starts successfully, the following messages would be shown on the console
- PatternMatching.siddhi - Started Successfully!
If you edit this application while it's running, stop the application -> Save -> Start.
Testing the Sample:¶
- Simulate single events. For this, click on 'Event Simulator' (double arrows on left tab) -> 'Single Simulation' -> Select 'PatternMatching' as 'Siddhi App Name' -> Select 'RoomTemperatureStream' as 'Stream Name' -> Provide attribute values -> Send
- To generate an alert, send one event, followed by another event (within 2 mins) where the temperature of the second event shows an increment by 5 degrees or more (eg. Temperature of event 1 = 17.0, Temperature of event 2 = 30.0). Note that these two events may or may not be consecutive.
Viewing the Results:¶
See the output on the console. Output will be shown if the second temperature input is incremented by 5 degrees or more.
Stop this Siddhi application, once you are done with the execution
@App:name("PatternMatching") @App:description('Identify event patterns based on the order of event arrival') define stream RoomTemperatureStream(roomNo string, temp double); @sink(type='log') define stream RoomTemperatureAlertStream(roomNo string, initialTemp double, finalTemp double); --Capture a pattern where the temperature of a room increases by 5 degrees within 2 minutes @info(name='query1') from every( e1 = RoomTemperatureStream ) -> e2 = RoomTemperatureStream [e1.roomNo == roomNo and (e1.temp + 5.0) <= temp] within 2 min select e1.roomNo, e1.temp as initialTemp, e2.temp as finalTemp insert into RoomTemperatureAlertStream;