JCA Error Handling Part 1 in SOA 11g

In this JCA Error Handling Part 1 we will learn the basic understanding of the jca errors,configuring Rejection Handlers by creating fault policies to handle them, and also ways to check this error messages
 

Rejected Messages

The messages that error out before being posted to the service infrastructure are referred to as rejected messages. 

For example, the Oracle File Adapter selects a file having data in CSV format and tries to translate it to XML format (using NXSD). If there is any error in the translation, this message is rejected and is not be posted to the target composite.

Primarily, adapters and binding components are the generators of rejected messages. Adapters reject messages that error out at the binding level; that is, they error out before entering the Service Infrastructure layer. All rejected messages are stored in the Database with the payload. The rejected messages can later be queried against.

Configuring Rejection Handlers

In the 10.x release, rejection handlers were defined in the deployment descriptor (bpel.xml) of an Oracle BPEL process.

In the 11g release, you must define rejection handlers by using fault policies. (You can specify only one action handler for inbound rejection handlers.)

Creating Fault Policies

You must create two files named fault-policies.xml and fault-bindings.xml, and copy them to the SOA project directory in JDeveloper

STEP.1: Define a fault policy for the rejected messages in the fault-policies.xml file, stored with the composite.xml file in the JDeveloper project directory, as follows

<?xml version="1.0" encoding="UTF-8"?>

<faultPolicies>

<faultPolicy version="2.0.1" id="RejectedMessages">

<Conditions> 

<!-- All the fault conditions are defined here -->

<faultName xmlns:rjm="http://schemas.oracle.com/sca/rejectedmessages" name="rjm:<SERVICE_NAME>">

<!-- local part of fault name should be the service name-->

<condition>

<action ref="writeToFile"/> 

<!-- action to be taken, refer to Actions section for the details of the action -->

</condition>

</faultName>

</Conditions>

<Actions> 

<!-- All the actions are defined here -->

<Action id="writeToFile">

<fileAction>

<location>/tmp/rej_msgs</location>

<fileName>emp_%ID%_%TIMESTAMP%.xml</fileName>

</fileAction>

</Action>

 </Actions>
</faultPolicy>
</faultPolicies> 

STEP.2: You must associate the fault policy with a service endpoint of the composite in fault-bindings.xml.

<faultPolicyBindings version="2.0.1"

xmlns="http://schemas.oracle.com/bpel/faultpolicy"

xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">

...

<service faultPolicy="RejectedMessages">

<name>Read</name>

</service>

...

</faultPolicyBindings>

STEP.3: Copy the fault-policies.xml and the fault-bindings.xml files to your SOA composite project directory.

STEP.4: Deploy the SOA composite project.

Note: If you do not configure rejection handlers as mentioned, a default file-based rejection handler starts processing and the rejected messages is directed to <domain_home>/rejmsgs/<wls_server_name>/<composite_name>.

Also, you can configure rejected messages with a Mediator Component in the same fault policy as that of Oracle BPEL Process Manager (Oracle BPEL PM).

Checking for Rejected Messages: You can check for rejected messages by using either of the following steps.

1. Checking from the Database

To check from the database, you must connect to the database as soainfra schema, and run the following SQL command:

select * from rejected_message

2. Checking from the Fusion Middleware Control Console

You can view the rejected messages in the Recent Faults and Rejected Messages section of the Dashboard tab or in the Faults and Rejected Messages tab.