Microservices is an architectural style and pattern that is becoming very popular and adopted by many organizations because of the advantages that it offers. In this book, you will learn what it takes to build great applications using microservices, the pitfalls associated with such a design, and the techniques to avoid them.
We will start by shedding light on traditional monoliths, and the problems faced in such architectures and how microservices are an obvious evolution to tackle such problems. We will then learn to build performant web-services using Play Framework. You will understand the importance of writing code that is asynchronous and non-blocking and how Play leverages this paradigm internally for a higher throughput.
Next, you will learn about the Reactive Manifesto and understand its practical benefits by leveraging it in your design. We will introduce the Lagom Framework, which serves two purposes: building reactive applications that are scalable and resilient to failures, and solving the problems associated with microservices architecture, such as service gateway, service discovery, inter-microservice communication and streaming, and so on. Message passing is used as a means to achieve resilience, and CQRS with Event Sourcing helps us model data for highly interactive applications.
We will proceed by learning about effective development processes for large teams. Using good version control workflow and continuous integration and deployments, we can achieve high confident shipment of code. Next, we will contrast it with an operating system level virtualization using Docker.
We will look at the theory of distributed systems first. This justifies the need for cluster orchestrator, such as Kubernetes, for efficient use of docker containers.
Finally, we will look at the actual end-to-end deployment of a set of Scala microservices completely in Kubernetes, with load balancing, service discovery, and rolling deployments.