Building Event-Driven Microservices, 2nd Edition

Chapter 17. Integrating Event-Driven and Request-Response Microservices

As powerful as event-driven microservice patterns are, they cannot serve all the business needs of an organization. Request-response communications are common in event-driven microservices, and you’ll often encounter them in scenarios such as:

• Collecting metrics from external sources, such as an application on a user’s cell phone or Internet of Things (IoT) devices

• Integrating with other request-response services, particularly third-party ones outside the organization

• Serving content in real time to web and mobile device users

• Serving dynamic requests based on real-time information, such as location, time, and weather

Event-driven patterns still play a large role in this domain, and integrating them with request-response solutions will help you leverage the best features of both.

Note

For the purposes of this chapter, the term request-response services refers to services that communicate with each other directly through calling each other’s API. Two services communicating via HTTP is a prime example of request-response communication. Communication may be synchronous (the calling service waits) or asynchronous (the calling service does other work while awaiting a callback).

This chapter covers three main subjects, including:

• Turning requests into events

• Integrating event-driven microservices with third-party APIs

• Building micro frontends

Turning Requests into Events

Many systems and services ...