Raible Designs

Building a REST API with JAXB, Spring Boot and Spring Data

If someone asked you to develop a REST API on the JVM, which frameworks would you use? I was recently tasked with such a project. My client asked me to implement a REST API to ingest requests from a 3rd party. The project entailed consuming XML requests, storing the data in a database, then exposing the data to internal application with a JSON endpoint. Finally, it would allow taking in a JSON request and turning it into an XML request back to the 3rd party.

With the recent release of Apache Camel 2.14 and my success using it, I started by copying my Apache Camel / CXF / Spring Boot project and trimming it down to the bare essentials. I whipped together a simple Hello World service using Camel and Spring MVC. I also integrated Swagger into both. Both implementations were pretty easy to create (sample code), but I decided to use Spring MVC. My reasons were simple: its REST support was more mature, I knew it well, and Spring MVC Test makes it easy to test APIs.

Camel's Swagger support without web.xml
As part of the aforementioned spike, I learned out how to configure Camel's REST and Swagger support using Spring's JavaConfig and no web.xml. I made this into a sample project and put it on GitHub as camel-rest-swagger.

This article shows how I built a REST API with Java 8, Spring Boot/MVC, JAXB and Spring Data (JPA and REST components). I stumbled a few times while developing this project, but figured out how to get over all the hurdles. I hope this helps the team that's now maintaining this project (my last day was Friday) and those that are trying to do something similar.

Developing Services with Apache Camel - Part IV: Load Testing and Monitoring

Welcome to the final article in a series on my experience developing services with Apache Camel. I learned how to implement CXF endpoints using its Java DSL, made sure everything worked with its testing framework and integrated Spring Boot for external configuration. For previous articles, please see the following:

• Part I: The Inspiration
• Part II: Creating and Testing Routes
• Part III: Integrating Spring 4 and Spring Boot

This article focuses on load testing and tools for monitoring application performance. In late July, I was asked to look into load testing the new Camel-based services I'd developed. My client's reason was simple: to make sure the new services were as fast as the old ones (powered by IBM Message Broker). I sent an email to the Camel users mailing list asking for advice on load testing.

In reply, I received suggestions for Apache's ab tool and Gatling. I'd heard of Gatling before, and decided to try it.

TL;DR

This article shows how to use Gatling to load test a SOAP service and how to configure Log4j2 with Spring Boot. It also shows how hawtio can help monitor and configure a Camel application. I hope you enjoyed reading this series on what I learned about developing with Camel over the past several months. If you have stories about your experience with Camel (or similar integration frameworks), Gatling, hawtio or New Relic, I'd love to hear them.

It's been a great experience and I look forward to developing solid apps, built on open source, for my next client. I'd like to get back into HTML5, AngularJS and mobile development. I've had a good time with Spring Boot and JHipster this year and hope to use them again. I find myself using Java 8 more and more; my ideal next project would embrace it as a baseline. As for Scala and Groovy, I'm still a big fan and believe I can develop great apps with them.

If you're looking for a UI/API Architect that can help accelerate your projects, please let me know! You can learn more about my extensive experience from my LinkedIn profile.

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Developing Services with Apache Camel - Part III: Integrating Spring 4 and Spring Boot

This article is the third in a series on Apache Camel and how I used it to replace IBM Message Broker for a client. I used Apache Camel for several months this summer to create a number of SOAP services. These services performed various third-party data lookups for our customers. For previous articles, see Part I: The Inspiration and Part II: Creating and Testing Routes.

In late June, I sent an email to my client's engineering team. Its subject: "External Configuration and Microservices". I recommended we integrate Spring Boot into the Apache Camel project I was working on. I told them my main motivation was its external configuration feature. I also pointed out its container-less WAR feature, where Tomcat (or Jetty) is embedded in the WAR and you can start your app with "java -jar appname.war". I mentioned microservices and that Spring Boot would make it easy to split the project into a project-per-service structure if we wanted to go that route. I then asked two simple questions:

1. Is it OK to integrate Spring Boot?
2. Should I split the project into microservices?

Both of these suggestions were well received, so I went to work.