@LiL95470

If you do not configure any responses, at run time, Pega Platform returns one of the following HTTP response codes by default:

• 200 – The request was processed without any errors.
• 500 – An error occurred during processing.
• 401 – An authentication problem occurred.

1. In your Service REST rule, click the Methods tab, and then click the method for which you want to construct a response.
2. Click the Response tab.
3. In the Condition field, select one of the following conditions:
   • Default – Send this response when there are no errors to report. If you plan to set up more than one condition, configure the Default condition as the last one in the list. To send an HTTP response code other than 200, specify a different code for the Default condition in the HTTP status code field.
   • When – The system evaluates the when condition specified by the When field. If the condition is true, the system returns the response message data. If the condition is false, the system evaluates the next when condition rule in the list. If all of the listed when condition rules are false, the system returns the default response data. Use this feature to extend the normal set of fatal error conditions that result in exceptions returned to the client, such as inappropriate inputs to the service activity, or other tests that you define.
   • Queue when – The system evaluates the when condition rule specified by the When field. If the condition evaluates to true, the system queues the service request and returns the queue item ID of the service request. If you configure a Queue When condition, you must specify a request processor in the Request Processor field on the Service tab. 
   • Mapping error – If an error occurs while mapping incoming data from a request message to the clipboard, the service returns the specified response message data. If the list of response conditions does not include an entry for mapping errors, Pega Platform returns the HTTP status code 500.
   • Security error – If an error occurs while authenticating the client credentials, Pega Platform returns the specified response message data. If the list of response conditions does not include an entry for security errors, Pega Platform returns the HTTP status code 401.
   • Service error – If a service error occurs, the system sends the specified response message data. If the list of response conditions does not include an entry for service errors, Pega Platform returns a standard error message.
4. If you set the conditional value to When or Queue when in step 3, in the When field, specify the name (the second key part) of a when condition rule to evaluate for this condition.

   The system uses the first key part (the Applies To class) of the service activity as the first key part of the when condition rule.