Service Discovery with Eureka and Zuul

Jarett Lear .NET, .NET Core, Articles, Microservices, Spring, Spring Boot 3 Comments

One issue that we face day to day as developers is speed of development. One of the coolest things to me in the ever-changing landscape of technology is how this issue us continually being addressed in an effort to makes our lives easier.

We have gone from having to write everything needed in a verbose way to being able to configure a simple REST API in a few lines of code with Spring Boot. The most amazing part of this is not only the ability to create the web services but also the ability to allow these services to communicate in a smart way. Spring has given us many tools to allow easy configuration and putting together things that just work (mostly).

This post is not to be considered a full guide to which the extent of these technologies can be leveraged. In this post, we give examples of how Spring Boot can be used (along with Zuul and Eureka) to create a simple discovery service.

There are other components that can be added for things like a configuration server to pull all application.properties files from a common location that is updatable in real time, or circuit breakers to allow the graceful failing of different pieces of your API.

What this post will focus on is the service discovery between Spring Boot applications. We will also touch on how, using SteeltoeOSS, .NET applications can also take advantage of being a part of the service discovery and be routed through our Spring Boot-based Zuul Gateway. We will also look at how we can integrate Spring Security into our gateway to secure the entire API no matter the language…

Why Am I Writing This Test?

Billy Korando Articles, Development Technologies & Tools, Effective Automated Testing With Spring Series, Testing Leave a Comment

… The highlight of this episode for me was when Dan laid out the three major concerns of automated tests. I hadn’t previously heard all the major purposes for automated testing laid out in such a succinct fashion. They are paraphrased:

Using Tests to Specify the Requirements of the System
Using Tests to Document the System
Using Tests to Build Confidence in the System

With purpose in mind, it is good practice for both developers and automated testers to ask themselves the following questions when writing a test: Why am I writing this test? Am I specifying system requirements? Documenting system behavior? Building confidence in the system? I’m a firm believer that asking the right questions when writing tests can lead to a better design for individual tests, in addition to more coherent and effective automated test suites.

In this article, we look into the three major purposes for writing automated unit tests. We discuss how they should be approached and what developers and automated testers can do right now to establish better, more purposeful, practices. 

Cucumber Testing in Spring Batch

Dallas Monson Articles, Development Technologies & Tools, Spring, Spring Batch, Testing 3 Comments

With the evolution of microservices and the scalable nature of modern distributed architectures, batch processing seems to be falling out of favor. In fact, the term batch processing itself seems to be unfavorably associated with monolithic mainframe applications and thus does not seem to have much appeal.

Unless, of course, you are working on a project that is being designed to replace or modernize one of those mainframe applications. If that is the case, then likely some sort of batch process has come up with a non-functional requirement that needs to be dealt with in the new system.

For this specific concern, a very powerful framework has been provided: Spring Batch. It has many of the same features of a mainframe batch process like restart/recovery, chunk processing, and error handling along with exit codes. This framework allows developers to create powerful batch processing applications in the Spring Framework and enjoy the rich backplane of capabilities that this provides.

Continuing with the modernization thread, you will likely be tasked with providing some assurances to the business that the new, modernized process will produce the same outcome as the one that is being replaced. Here is where testing comes in, and where Cucumber specifically shines.

Cucumber provides behavioral testing support in the Spring universe. This allows developers and business users to collaborate through a common set of conventions and verbiage to validate that the app is behaving how the business intended as well as how the developer coded it.

In this post we will cover the following:
Why use Cucumber with Spring Batch
An overview of Cucumber and an example Cucumber Test
How to start with Cucumber and Spring Batch…

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Pseudo-Static Row Mappers, a Healthy Alternative to Static Row Mapping

Ryan McCullough Articles, Java, Spring Leave a Comment

If you know Spring, chances are pretty good that you’ve also worked with RowMappers and everyone’s #1 favorite BeanPropertyRowMapper. Okay, maybe not EVERYONE. But EVERYONE will acknowledge BPRM’s power potential and how wonderfully easy it is to use!

While BeanPropertyRowMapper may be the smartest and most beautiful on the RowMapper block, many in the industry refuse to give it the time of day, and for perfectly justified reasons.

Sometimes, when we can’t have beauty and wisdom, we’re forced to settle for loud and predictable. Yes, I’m talking about hardcoded, unchanging, tell-it-like-it-is, static RowMapper. Hate on them all you like, Static RowMappers are fast, easy to understand, and they seem to replicate like tribbles.

But, as many of you know, an application can grow into a swamp of one-off RowMappers. ESPECIALLY if you are working with a lot of high-throughput batch operations that need to run strictly optimized queries for performance as to avoid any unnecessary marshaling of data.

Recently, I’ve tried a mildly clever alternative to RowMapping I like to call Pseudo-Static Row Mappers. In this post, I introduce the basics of Pseudo-Static Row Mappers. We show how they give the tough rigid optimization and control of hard-coded naming and data typing while retaining BeanPropertyRowMapper’s spirit of freedom.

Keyhole Sponsoring Azure Dev Days Kansas City 2018

Keyhole Software .NET, Articles, Azure, Cloud, Community, Company News, Educational Event Leave a Comment

We are excited to announce Keyhole’s partnership with Microsoft to sponsor Azure Dev Days, a one-day workshop in Kansas City on Wednesday, April 25, 2018. This is a free community event to provide education on application modernization, microservices, and Microsoft Azure topics.

In addition to providing technical educators for this workshop, Keyhole Software will sponsor food and beverages. The topics Keyhole will champion include Microservices and Containers, as well as App Services.

Each technical session will be followed by a hands-on Azure lab and a whiteboard design exercise. This workshop will help attendees gain a thorough understanding of the components of Azure and how you can take advantage of them as a developer.

This is a traveling community event, with other events available to attend in St. Louis and Oklahoma City. The event will be held at the Microsoft offices in Overland Park…