Raible Designs

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.

Developing Services with Apache Camel - Part II: Creating and Testing Routes

This article is the second in a series on Apache Camel and how I used it to replace IBM Message Broker for a client. The first article, Developing Services with Apache Camel - Part I: The Inspiration, describes why I chose Camel for this project.

To make sure these new services correctly replaced existing services, a 3-step approach was used:

1. Write an integration test pointing to the old service.
2. Write the implementation and a unit test to prove it works.
3. Write an integration test pointing to the new service.

I chose to start by replacing the simplest service first. It was a SOAP Service that talked to a database to retrieve a value based on an input parameter. To learn more about Camel and how it works, I started by looking at the CXF Tomcat Example. I learned that Camel is used to provide routing of requests. Using its CXF component, it can easily produce SOAP web service endpoints. An end point is simply an interface, and Camel takes care of producing the implementation.

Developing Services with Apache Camel - Part I: The Inspiration

In early May, my client asked me to work on a project migrating from IBM Message Broker 6.1 to an open source solution. Their reason was simple, the IBM solution was end of life and outdated. To prove how out of date it was, the Windows version required Windows XP to run. IBM WebSphere Message Broker has been replaced by IBM Integration Bus in recent years, but no upgrade path existed.

At first, I didn't want to do the project. I was hired as a Modern Java/UI Architect and I had enjoyed my first month upgrading libraries, making recommendations and doing a bit of UI performance work. I hadn't done much with ESBs and I enjoy front-end development a lot more than backend. It took me a couple days to realize they were willing to pay me to learn. That's when I decided to clutch up, learn how to do it all, and get the job done. This article is the first in a series on what I learned during this migration project.

My approach for figuring out how everything worked was similar to working on any new application. I get the source code, install the software necessary to run it, and run it locally so I can interact with it.

Getting Started with JHipster on OS X

Last week I was tasked with developing a quick prototype that used AngularJS for its client and Spring MVC for its server. A colleague developed the same application using Backbone.js and Spring MVC. At first, I considered using my boot-ionic project as a starting point. Then I realized I didn't need to develop a native mobile app, but rather a responsive web app.

My colleague mentioned he was going to use RESThub as his starting point, so I figured I'd use JHipster as mine. We allocated a day to get our environments setup with the tools we needed, then timeboxed our first feature spike to four hours.

My first experience with JHipster failed the 10-minute test. I spent a lot of time flailing about with various "npm" and "yo" commands, getting permissions issues along the way. After getting thinks to work with some sudo action, I figured I'd try its Docker development environment. This experience was no better.

JHipster seems like a nice project, so I figured I'd try to find the causes of my issues. This article is designed to save you the pain I had. If you'd rather just see the steps to get up and running quickly, skip to the summary.

Why I prefer IntelliJ IDEA over Eclipse

Over the last couple months, I've received a few emails asking why I prefer IntelliJ IDEA over Eclipse. They usually go something like this:

I keep seeing you recommending IntelliJ. I keep trying it intermittently with using Eclipse, but I feel like I'm missing something obvious that makes so many people think it's better. Granted having the usual plugins incorporated is nice, but other things like the build process and debugger sometimes seems a step back from Eclipse. Could you please blog a '10 reasons why I love IntelliJ' or point me to something that would clue me in?

I grew to love IntelliJ for a few reasons. It all started in 2006 when I decided to migrate AppFuse from Ant to Maven. Before that, I was a huge Eclipse fan (2002 - 2006). Before Eclipse, I used HomeSite, an HTML Editor to write all my Java code (1999-2002). Eclipse was the first IDE that didn't hog all my system's memory and was pleasant to work with.

The reason I started using IntelliJ in 2006 was because of it's multi-module Maven support. Eclipse's Maven support was terrible, and m2e hasn't gotten a whole lot better in recent years AFAIK.

Back then, I used to think everything should be built and run from the command line. A couple years later, I realized it was better to run tests and debug from an IDE. Now I'm more concerned with the ability to run tests and debug in an IDE than I am from the build system.

In 2009, I started doing a lot more front-end work: writing HTML, CSS and JavaScript. I also started digging into alternate languages for these: Jade, GWT, CoffeeScript, LESS, SASS - even Scala. I found IntelliJ's support, and plugins, to be outstanding for these languages and really enjoyed how it would tell me I had invalid JavaScript, HTML and CSS.

My original passion in software was HTML and JavaScript and I found that hasn't changed in the last 15 years. AFAIK, Eclipse still has terrible web tools support; it excels at Java (and possibly C++ support). Even today, I write most of my HTML code (for InfoQ and this blog) in IntelliJ.

In reality, it probably doesn't matter which IDE you use, as long as you're productive with it. Once you learn one IDE well, the way others do things will likely seem backwards. I'm so familiar with debugging in IntelliJ, that when I tried to use Eclipse's debugger a few weeks ago, it seemed backwards to me.

In a nutshell: the technologies I've worked with have been better embraced by IntelliJ. Has this happened to you? Have certain technologies caused you to use one IDE over another?

How do you stay current with emerging technologies?

I recently received an email from a former co-worker. She was curious to know what I read/do to know what it is "trending" in the software world. I think this is good knowledge to share, and I'm also interested in what others do to keep up. Here's my response to her:

My technique for staying up-to-date is mostly reading, and attending some user group meetings. For reading, I read news.ycombinator.com, as well as infoq.com - who I now write for. DZone.com (esp. Javalobby and its HTML5 Zone) is also pretty good, as is arstechnica.com. I don't read nearly as much as I used to when I was subscribed to all of their RSS feeds and read them religiously.

Nowadays, most of my information comes from Twitter. I follow people that are involved in technologies I'm interested in. I try to keep the number of people I follow to 50 as I don't want to spend too much time reading tweets.

For meetups, most are on meetup.com these days. I'd find a couple that have technologies you're interested in (e.g. a local HTML5 meetup or Java user group) and join the group. You'll get email notifications when they have meetings.

Other than that, sometimes I do "conference driven learning". I'll pick a few technologies I'm interested in learning, submit a talk to a conference or user group, then be forced to learn and present on them when it gets accepted. It can be stressful, but it works and usually results in a good presentation because I can share the experience of learning.

One interesting thing I've realized about Twitter is I can make technologies seem "hot" based on the people I follow. If I'm following a bunch of AngularJS folks, my feed is filled with Angular-related tweets and it seems like the hottest technology ever. If I tweak who I follow to have a bunch of Groovy enthusiasts, or Scala folks, the same thing happens.

Of course, the best way to learn new technologies is to use them in your daily job. I strive to do this with my clients, but it doesn't always work out. I've found that working on open source projects and speaking at conferences can help you learn if you're in a stagnant environment. Then again, if you're not happy at work, quit.

What do you do to stay on top of emerging trends in technology?

First Devoxx4Kids in Denver a Wild Success!

The first Devoxx4Kids Denver was a wild success! This last Saturday, 20 enthusiastic Minecraft hackers gathered at Thrive in Cherry Creek to learn from one of the best. With masterful skill, Scott Davis, founder of ThirstyHead.com, taught everyone how to get a development environment setup, run a local Minecraft server and install plugins into it. You can see the materials we used for this class on Scott's site, at Introduction to Server-side Minecraft Programming.

McGinity Photo was kind enough to snap a bunch of pictures, which you can find on Flickr. A sampling is below:

Devoxx4Kids - Denver Chapter Begins!

I'm happy to announce the first meeting of the Denver Chapter of Devoxx4Kids is now open for registration. It's a two hour class titled Introduction to Server-Side Minecraft Programming and will be taught by Denver's own Scott Davis. The class will be held on May 3rd, from 10am - 12pm at Thrive's Cherry Creek location, where we can comfortably fit 20 students. Cost is $10, but you'll get that back in the form of a t-shirt. Age requirement is 9-18 and kids should have basic computer skills (copy/paste, opening applications, etc.). Minecraft experience will certainly help too.

I'd like to thank Daniel De Luca for his initial assistance with getting Devoxx4Kids setup in Denver and Arun Gupta for starting Devoxx4Kids USA. Arun has been a great help in getting things going and answering my questions over the last few months. Of course, none of it would be happening without Scott Davis or Thrive. If you join us on May 3rd, you'll see that Scott is an awesome teacher and Thrive has some incredible facilities.

My initial goal with Devoxx4Kids in Denver is to host a class or two this year. If there's enough demand, we can expand. For now, we're starting small and seeing where it takes us. If you're interested in teaching a future class, please let me know. We'd love to teach the kids a number of skills, from Scratch to NAO Humanoid Robot programming to building things with Arduino and Raspberry Pi.

Documenting your Spring API with Swagger

Over the last several months, I've been developing a REST API using Spring Boot. My client hired an outside company to develop a native iOS app, and my development team was responsible for developing its API. Our main task involved integrating with Epic, a popular software system used in Health care. We also developed a Crowd-backed authentication system, based loosely on Philip Sorst's Angular REST Security.

To document our API, we used Spring MVC integration for Swagger (a.k.a. swagger-springmvc). I briefly looked into swagger4spring-web, but gave up quickly when it didn't recognize Spring's @RestController. We started with swagger-springmvc 0.6.5 and found it fairly easy to integrate. Unfortunately, it didn't allow us to annotate our model objects and tell clients which fields were required. We were quite pleased when a new version (0.8.2) was released that supports Swagger 1.3 and its @ApiModelProperty.

What is Swagger?
The goal of Swagger is to define a standard, language-agnostic interface to REST APIs which allows both humans and computers to discover and understand the capabilities of the service without access to source code, documentation, or through network traffic inspection.

To demonstrate how Swagger works, I integrated it into Josh Long's x-auth-security project. If you have a Boot-powered project, you should be able to use the same steps.