getContactMetrics  
  Retrieves the position of the contact in the queue.
Use cases
Following are common uses cases for position in queue:
- Understand the expected wait experience of a contact. 
- Inform customers of their position in queue and potentially offer a callback. 
- Make data-driven routing decisions between primary and alternative queues. 
- Enhance queue visibility and leverage agent proficiencies to streamline contact routing. 
Important things to know
- The only way to retrieve the position of the contact in queue is by using this API. You can't retrieve the position by using flows and attributes. 
- For more information, see the Position in queue metric in the Amazon Connect Administrator Guide. 
Endpoints: See Amazon Connect endpoints and quotas.