File-tail Event Receiver

File-tail event receiver reads the tail of a given file and feeds that to the product engine. It only supports text input mapping type.

Creating a file-tail event receiver

For instructions on creating a file-tail event receiver, see Configuring Event Receivers.

Configuring global properties

The following global property can be set for the file-tail event receiver type in the <CEP_HOME>/repository/conf/input-event-adapters.xml file. This property applies to all the receivers of the file-tail type. If this property is removed from the file, its default value still applies.

Property Key	Description	Data Type	Default Value
`events.duplicated.in.cluster`	If this property is set to `true`, events received by file-tail receivers are re-created in every node in the cluster.	Boolean	`false`

Configuring adapter properties

Specify the Adapter Properties, when creating a file-tail event receiver using the management console as shown below.

After entering the above adapter properties, select the Event Stream to which you want to map the incoming events, and the Message Format which you want to apply on the receiving events . Also, click Advanced to define custom input mappings based on the Message Format you selected. For more information on custom input mapping types, see Input Mapping Types.

You can also d efine the respective adapter properties of the event receiver based on the transport type within the <from> element of the event receiver configuration in the <PRODUCT_HOME>/repository/deployment/server/eventreceivers/ directory as follows.

<eventReceiver name="FileTailInputEventAdapter" statistics="disable" trace="disable" xmlns="http://wso2.org/carbon/eventreceiver">
    <from eventAdapterType="file-tail">
        <property name="filepath">/User/Desktop/abc.txt</property>
        <property name="startFromEnd">true</property>
        <property name="delayInMillis">10</property>
    </from>
   .............................
</eventReceiver>

The above adapter properties are described below.

Adapter property	Description	Configuration file property	Example
File path	Absolute path of the text file to read the data from.	filepath	/Users/User/Desktop/abc.txt
Delay	The delay between checks for new content on file in milliseconds.	delayInMillis	10
Start From End	Set to true to tail from the end of the file, false to tail from the beginning of the file.	startFromEnd	true

Related samples

For more information on file-tail event receiver type, see the following samples.