Chapter 5 Designing the integration Layer Microservices The microservices architectural integration technology stack contains a suite of small services, each running its own process and communicating with lightweight mechanisms on an individual port number. One service would contain one business capability, as shown in Figure 5-5. OTP services have OTP capabilities; similarly, other services have their own process and lifecycle. These services are separately deployable, hence a faster release cycle. You can use different microservices frameworks such as SpringBoot, Lagom, etc., as shown in Figure 5-5. Figure 5-5. Microservices ESB and API Gateway An ESB would be used for integration, orchestration of multiple services into one service, routing of services, and event handling and monitoring. An ESB is based on service-oriented architecture, which is an efficient service delivery platform. On top of an ESB, you could use a service gateway for security, policy enforcement, and exposing services as an open API to external consumers (public). A service gateway manages your integration services built with an ESB. 170