Pre-processing Data Received via TCP


This example demonstrates how to receive events via the TCP transport and carry out data pre-processing with numerous Siddhi extensions (e.g., string extension, time extension). In this sample, a composite ID is obtained using string concatenation and the time format of the incoming event is changed from yyyy/MM/dd HH:mm:ss to dd-MM-yyyy HH:mm:ss.

For more information about Siddhi extensions, see Siddhi Extensions.

Before you begin:

Save the sample Siddhi application in Streaming Integrator Tooling.

Executing the Sample

To execute the sample open the saved Siddhi application in Streaming Integrator Tooling, and start it by clicking the Start button (shown below) or by clicking Run => Run.

Start button

If the Siddhi application starts successfully, the following messages appear in the console.

  • Tcp Server started in

  • DataPreprocessing.siddhi - Started Successfully!


If you want to edit the Siddhi application after you have started it, stop it first, make your edits, save it and then start it again.

Testing the Sample

To test this Siddhi application, navigate to the <SI_TOOLING_HOME>/samples/sample-clients/tcp-client directory and run the ant command as follows.

ant -Dtype=json -DfilePath={WSO2SIHome}/samples/artifacts/DataPreprocessing/data_preprocessing_events.txt -DeventDefinition='{"event":{"id":"{0}","value":{1},"property":{2},"plugId":{3},"householdId":{4},"houseId":{5},"currentTime":"{6}"}}' -Durl=tcp://localhost:9892/SmartHomeStream

Viewing the Results

Once the DataProcessing Siddhi application receives events from the TCP client, the following messages are displayed in the Streaming Integrator Tooling console:

INFO {} - DataPreprocessing : ProcessedStream : Event{timestamp=1513621173211, data=[HouseholdID:1::UniqueID:0001, 12.12, 13-08-2001 23:49:33], isExpired=false}

INFO {} - DataPreprocessing : ProcessedStream : Event{timestamp=1513621174202, data=[HouseholdID:2::UniqueID:0002, 13.12, 13-08-2004 23:49:34], isExpired=false}

INFO {} - DataPreprocessing : ProcessedStream : Event{timestamp=1513621175208, data=[HouseholdID:3::UniqueID:0003, 13.12, 13-08-2006 23:49:35], isExpired=false}

INFO {} - DataPreprocessing : ProcessedStream : Event{timestamp=1513621176214, data=[HouseholdID:4::UniqueID:0004, 14.12, 13-08-2008 23:49:36], isExpired=false}

Click here to view the sample Siddhi application.

@App:description('Collect data via TCP transport and pre-process')

@Source(type = 'tcp',
define stream SmartHomeStream (id string, value float, property bool, plugId int, householdId int, houseId int, currentTime string);

define stream ProcessedStream (compositeID string, value float, formattedTime string);

--Process smart home data by concatenating the IDs and formatting the time
from SmartHomeStream
select str:concat("HouseholdID:", convert(householdId, "string"), "::", "UniqueID:", id) as compositeID, value, str:concat(currentTime, " ", time:currentTime()) as formattedTime
insert into ProcessedStream;