Microservices for Java Developers

Chapter 3. Dropwizard for Microservices

Dropwizard was created well before either Spring Boot or WildFly Swarm (the other two microservices frameworks we’re looking at in this book). Its first release, v0.1.0, came out December 2011. At the time of this writing, v0.9.2 is the latest, and 1.0 is just around the corner. Dropwizard was created by Coda Hale at Yammer to power the company’s distributed-systems architectures (now called microservices!), heavily leveraging the JVM. It started out as a set of glue code to combine some powerful libraries for writing REST web services and has evolved since then, although it still maintains its identity as a minimalist, production-ready, easy-to-use web framework.

Dropwizard is an opinionated framework like Spring Boot; however, it’s a little more prescriptive than Spring Boot. There are some components that are just part of the framework and cannot be easily changed. The sweet-spot use case is writing REST-based web applications/microservices without too many fancy frills. For example, Dropwizard has chosen the Servlet container (Jetty), REST library (Jersey), and serialization and deserialization (Jackson) formats for you. Changing them out if you want to switch (i.e., changing the servlet container to Undertow) isn’t very straightforward.

Dropwizard also doesn’t come with a dependency-injection container (like Spring or CDI). You can add one, but Dropwizard favors keeping development of microservices simple, with no magic. Spring Boot ...