How to Send and Update Reference Fields in ServiceNow

In ServiceNow, all information is stored in tables. The tables refer to each other with reference fields. This documentation shows you how to send and update reference fields with Exalate for ServiceNow.

Sending Reference Fields

ServiceNow REST API returns different results when the field is empty or not empty:

• If the field is empty, it returns an empty string value.
• If the field is not empty, it returns an object with the display value and a link to the reference field table.

To send a reference field, we need to make sure that it is not empty with a script:

//Outgoing script
if(incident.caller_id && incident.caller_id != ""){
   //We only get inside this block if the caller_id has a value
   replica.caller = incident.caller_id.display_value
}

The script returns the display value.

In some cases, we need to retrieve other information with the display value. To do so, we can use a link to the table and nodeHelper.getTableByLink. This method gets the full content of the reference field.

Example:

//Outgoing script
if(incident.caller_id && incident.caller_id != ""){
  //We only get inside this block if the caller_id has a value
  replica.callerMail = nodeHelper.getTableByLink(incident.caller_id?.link)?.email
}

You can replace the email value to get other information, for example, a user name.

If you want to get a specific value from the table, you can use nodeHelper.getReference. In the script, you can specify the table name.

Example:

//Outgoing script
 replica.johnUserName = nodeHelper.getReference("sys_user", "email", "john@snow.com")?.name

You can replace the following parameters:

sys_user

Name of the table.

email

Name of the table column.

john@snow.com

The value in the column.

Updating Reference Fields

You can update reference fields by using their sys_id value.

Example of getting the field status:

//Incoming Script
incident.incident_state = "9"

//Incoming script
def remoteEmail = replica.reporter?.email
if(remoteEmail){
   incident.caller_id = nodeHelper.getReference("sys_user", "email", remoteEmail)?.sys_id
}

You can replace the following parameters:

sys_user

Name of the table.

email

Name of the table column.

Example of getting a reference id by using a Jira custom field:

//Incoming script
//Receiving a value from a Jira Custom Field where the CF name is "Jira Custom Field name"
def remoteAssignmentGroup = replica.customFields."Jira Custom Field name"?.value
incident."assignment_group" = nodeHelper.getReference("assignment_group", "name", remoteAssignmentGroup)?.sys_id