Data Service job automatically validates required parameters, if any. In the case of a missing required parameter (status code 400 by default), it returns a status code and reason phrase specified for Invalid request.

Any other failure during graph execution results in an error response - status code 500 by default and "Job execution failed".

You can override default status codes for predefined states: Success, Invalid request or Error state in Endpoint Configuration.

It is also possible to use more specific status codes to provide more precise information about the error, if needed. In such a case, use the setResponseStatus() CTL function. Status code specified using the CTL function will override status codes defined in Endpoint Configuration.

If you want to fail fast and in a controlled fashion while returning your on HTTP response code and message, use setResponseStatus(code, message), then terminate the processing using a standard raiseError() function.

Data Service generates built-in error status codes for various infrastructure problems.

If your consumers have difficulty connecting to your Data Service endpoints, i.e. you suspect they are not accessible or published correctly, check your application server access.log. For Tomcat, this is located at ${TOMCAT_HOME}/logs/localhost_access_log.