This is only for minimum Mule version 4.2.x onwards

This custom error handler plugin allows a single module to process error messages from multiple types:

• Error types default to mule. (HTTP, APIKIT, Connectors based, etc)
• custom error types as defined by raise error component.
• Un-clutter exceptions both in UI and XML
• User can change the custom error message (for multiple errors) in the UI rather than in the XML.
• Users intending to use other error types should put them on on-error-propagate or on-error-continue prior to using this module.
• No specific error type is required for this module. It can parse any error types.
• Propagate errors from sys/prc layer back to exp layer, cementing error propagation across layers.
• To propagate the errors, ensure the appropriate variable name is referenced in the previous error section.

On Error

To deploy to Exchange, run the script named deploy.sh as follows,

./deploy.sh <YOUR_ORG_ID>

Please ensure that your settings.xml has been configured with the correct Exchange credentials so that the publish can succeed.

For local install, give any groupId. Issue mvn clean install

Add this dependency to your application pom.xml

<dependency>
	<groupId>${groupId}</groupId>
	<artifactId>common-error-handler</artifactId>
	<version>${version}</version>
	<classifier>mule-plugin</classifier>
</dependency>

• Delete the auto-generated error blocks (on-error-propagate/on-error-continue) before using this module.
• Place the plugin inside an error block (on-error-propagate/on-error-continue) along with a variable for httpStatus.

The error response should be changed to the following to send back the populated error message.

<http:listener doc:name="Listener" doc:id="1d3566ad-c8dc-4b8a-ab45-338625c74afb" config-ref="HTTP_Listener_config" path="/error">
	<http:response statusCode="#[vars.httpStatus default 200]">
		<http:headers>#[vars.outboundHeaders default {}]</http:headers>
	</http:response>
	<http:error-response statusCode="#[vars.httpStatus default 500]">
		<http:body>#[payload]</http:body>
		<http:headers>#[vars.outboundHeaders default {}]</http:headers>
	</http:error-response>
</http:listener>

• Takes values for apiName and apiVersion. Current default values will be read from a property file api.name and api.version respectively.
• Takes value for the previous error message that needs to be propagated. It has to be of type array.
• Error section defines from what mule expression should the error be read.
• httpStatus set variable is required to send back the httpStatus on the http response

httpStatus variable must be set for the http listener to return on the request

Common HTTP based errors are defined in this section. Users have to provide the message they want to send back on the API error response.

Currently due to a limitation on XML SDK, text based entries are required for custom errors. The number of entries have to match else it will fail to be successfully executed.

errorTypes: Have to provided as , separated values. Example : DB:BAD_SQL_SYNTAX, ABC:DEF errorCodes: Have to provided as , separated values. Example : 500, 599 errorMessages: Have to provided as , separated values. Example : SQL Syntax is incorrect, Testing

A correlationId will be used for tracking transactions. The default value is #[correlationId]

<error-handler>
	<on-error-propagate enableNotifications="true"
		logException="true" doc:name="On Error Propagate" doc:id="b995ec19-3b56-4b8e-8b0f-b172cead9be4">
		<error-handler-plugin:on-error doc:name="On error" doc:id="42db8478-b083-48b4-b31f-6638e6a6f18a" />
		<set-variable value="#[attributes.httpStatus]"
			doc:name="Set Variable" doc:id="2151ced0-a42f-4c0d-b439-455abd354277"
			variableName="httpStatus" />
	</on-error-propagate>
</error-handler>

<on-error-propagate enableNotifications="true" logException="true" doc:name="On Error Propagate" doc:id="b995ec19-3b56-4b8e-8b0f-b172cead9be4">
	<error-handler-plugin:on-error doc:name="On error" 
		doc:id="2108e03c-1a96-4dcd-976e-26d9f5f5f158" 
			errorTypes="DB:BAD_SQL_SYNTAX, ABC:DEF" 
			errorCodes="500, 599" 
			errorMessages="SQL Syntax is incorrect, Testing"/>
	<set-variable value="#[attributes.httpStatus]"
		doc:name="Set Variable" doc:id="2151ced0-a42f-4c0d-b439-455abd354277"
		variableName="httpStatus" />
</on-error-propagate>

Imtiyaz Qureshi, Salim Khan, Biswaranjan Mohanty