Hands-On RESTful Web Services with Go - Second Edition

Delaying API jobs with queuing

In synchronous APIs, the blocking code plays a crucial role in preparing the response that is sent to the client. However, in the asynchronous design, non-blocking is key. A queue and workers can be helpful in achieving non-blocking code. A server can have multiple workers running in parallel who can exhaust the contents of a queue and work on them. Whenever a client requests an operation through an asynchronous API, the server can put that request in a job queue, and all the workers can pick up a task whenever their turn comes.

This approach can offload an API server and focus on its business logic instead of getting blocked on parallel/independent tasks such as sending emails, contacting third-party services, ...