You can configure execution plans through the management console as explained below or by manually adding an XML file as explained in step 5.
- Start the CEP, log in to its management console, select Execution Plans and click Add Execution Plan.
- Enter details in the form that appears.
The fields in the above configuration are described below:- Execution Plan Name : Can contain only alphanumeric characters and '_' character
- Description : This is optional
- Snapshot time interval : Defines how often the state of the processing engine should be persisted, which is used to restore after a system crash. The default value is 0, which disables this feature. If snapshot is enabled, you must start the CEP with the embedded Cassandra server enabled. To do this, specify -Ddisable.cassandra.server.startup=false option at server startup.
- Query expressions: See Siddhi Language Specification on how to write queries. When writing query expressions, you must import the required streams from event builders. The As field maps the incoming stream to a stream name suitable for the Siddhi processing engine. It can contain only alphanumeric characters and '_' character.
In the text field that follows imported streams, you can enter any number of CEP statements, each ending with a semicolon. For example,
The Exported streams section allows you to expose the output streams from Siddhi to the event formatter with preferred stream IDs. For example,
- fsdf
Once all mandatory fields are filled, users can add the execution plan. If the execution plan deploys successfully, it will be displayed under the available execution plans section in Event Processor menu.
Please use a character string which starts with alphabetic for streamId because in siddhi level it is considered as a java variable. Here Stream Id is a combination of stream name and version. Eg: testStream:1.0.0
Editing an Execution Plan Configuration through the Management Console
By Clicking the Edit button of the relevant execution plan, you will able to edit the execution plan configuration and redeploy it. When you click the Edit button, it will redirect to a xml based editor window which allows you to edit the execution plan configuration from UI without opening the configuration file in the file system.
Configuring through an XML file
You can specify an execution plan configuration through an xml file and deploy it in the deployment directory of the server. Execution Plan deployment directory is located at <CARBON_HOME>/repository/deployment/server/executionplans . This is a hot deployment directory and execution plan configurations can be easily deployed and undeployed by placing/removing the xml file there.
1. Create a xml file, enter the execution plan configuration details.
2. Place the file inside the above mentioned hot deployment directory. Note that Execution plan configurations need to start with "executionplan" root element.