Message Queue

You might say

Don't make the user stare at a spinner while generating this huge report. Put the job into a message queue and let background workers process it.

A communication and decoupling mechanism that temporarily stores messages between senders and receivers so neither must wait synchronously.When a user exports a large report, the API creates a job, writes its ID and parameters to a queue, and immediately returns a pending status. A worker generates the file and updates the same ID to completed or failed. Enqueueing proves receipt, not completion, and retries can cause the same job to be delivered again.
MQMessage Broker
Further reading