DenverJUG

Wednesday, September 11, 2019

5:30-6:00: Food, Soda, Beer, and Networking

6:00-6:15: Announcements

6:15-7:45: Bootiful Reactive Testing

Join us for an exploration of testing a reactive Spring Boot 2.x application. Test-driven development gives us the confidence necessary to improve our code faster, safely. But how do you test components and services, as well as integrations across distributed systems, while maintaining fast feedback loops, and how do you do all of this within the context of reactive Java? In this talk, we’ll look at how to test imperative components, reactive data flows, and mocks. We’ll examine how to take advantage of test slices, and how to test web applications. We’ll look at how to ensure that API producers and consumers work well together using consumer-driven contract testing without sacrificing the testing pyramid for end-to-end integration tests. And we’ll do it all within the context of reactive programming.

About Mario Gray

Currently a Principal Technologist for Pivotal. Mario has worked in software for startups and large financial services enterprises alike working across the stack from server/network design to application design. He’s professionally written software to entertain, bring people together, and drive businesses using technologies like Linux/Solaris,SQL/NOSQL,AWS/SALT,Spring/J2EE. Mario is confident that the future of cloud computing belongs to Pivotal and the Spring team for some time to come. A longtime open-source champion, Mario is co-author of Apress’ Pro-Spring Integration, as well as a contributor to the Spring and Integration projects.

You can find Mario on Twitter @mariogray (https://twitter.com/mariogray).

7:45: Door prizes

* IntelliJ IDE License (https://www.jetbrains.com/idea/)

* Pluralsight Subscription provided by DevelopIntelligence (http://www.developintelligence.com/)

8:15: After Meeting Networking

After meeting networking sponsored by Okta (https://developer.okta.com/). We meet at Ale House at Amato’s (2501 16th St, Denver, CO 80211).

Wednesday, August 14, 2019

Wednesday, July 10, 2019

5:30-6:00: Food, Soda, Beer and Networking

6:00-6:15: Announcements

6:15-7:45: Building Stateful Clustered Microservices with Java, Actors, and Kubernetes

When building microservices or web apps, we often take the path of least resistance and go with a stateless approach. The justification is that going the stateful route is too hard and too complicated. Based on the state of the tools that we typically use to build apps, going stateless is a wise decision given that the commonly used backend toolsets and frameworks tend to shy away from dealing with distributed, clustered systems.

However, with the spectacular rise of Kubernetes, many developers are diving head first into the clustered world. This mass migration to the clustered, scalable, and resilient Kubernetes playing field opens up new opportunities for how we build systems. One of the new ways of doing things is the actor model. In the pre-Kubernetes world, everything is an object; in the post-Kubernetes world, everything is an actor. Actors are fundamental building blocks, like objects, that are stateful, are inherently concurrent, and with the Akka Toolkit, systems of actors naturally exist and collaborate in clustered environments.

In this talk, we will explore some theory and code of a live actor system based microservice running in a clustered Kubernetes environment.

About Hugh McKee

Hugh McKee is a developer advocate at Lightbend. He has had a long career building applications that evolved slowly, that inefficiently utilized their infrastructure, and were brittle and prone to failure. Hugh has learned from his past mistakes, battle scars, and a few wins. And the learning never stops. Now his focus is on helping other developers and architects build resilient, scalable, reactive, distributed systems.

7:45: Door prizes

* IntelliJ IDE License (https://www.jetbrains.com/idea/)
* Pluralsight Subscription provided by DevelopIntelligence (http://www.developintelligence.com/)

8:15: After Meeting Networking

After meeting networking sponsored by Okta (https://developer.okta.com/). We meet at Ale House at Amato’s (2501 16th St, Denver, CO 80211).

Wednesday, June 12, 2019

5:30-6:00: Food, Soda, Beer and Networking

6:00-6:15: Announcements

6:15-7:45: Dissolving the Problem: Kafka is more ACID Than Your Database

It has become a truism in the past decade that building systems at scale, using non-relational databases, requires giving up on the transactional guarantees afforded by the relational databases of yore, ACID transactional semantics are fine, but we all know you can’t have them all in a distributed system. Or can we?

In this talk, I will argue that by designing our systems around a distributed log like Kafka, we can in fact achieve ACID semantics at scale. We can ensure that distributed write operations can be applied atomically, consistently, in isolation between services, and of course with durability. What seems to be a counterintuitive conclusion ends up being straightforwardly achievable using existing technologies, as an elusive set of properties becomes relatively easy to achieve with the right architectural paradigm underlying the application.

About Tim Berglund

Tim is a teacher, author, and technology leader with Confluent, where he serves as the Senior Director of Developer Experience. He can frequently be found at speaking at conferences in the United States and all over the world. He is the co-presenter of various O’Reilly training videos on topics ranging from Git to Distributed Systems and is the author of Gradle Beyond the Basics. He tweets as @tlberglund, blogs very occasionally at http://timberglund.com, is the co-host of the http://devrelrad.io podcast and lives in Littleton, CO with the wife of his youth and their youngest child, the other two having mostly grown up.

7:45: Door Prizes

* IntelliJ IDE License (https://www.jetbrains.com/idea/)
* Pluralsight Subscription provided by DevelopIntelligence (http://www.developintelligence.com/)

8:00: After Meeting Networking

After meeting networking sponsored by Okta (https://developer.okta.com/). We meet at Ale House at Amato’s (2501 16th St, Denver, CO 80211).

Wednesday, May 8, 2019

5:30-6:00: Food, Soda, Beer and Networking

6:00-6:15: Announcements

6:15-7:45: Functions and Typeclasses in Scala with Daniel Hinojosa

Not going to lie to you, I think Scala is pretty great. I have very few complaints about it and that’s a rarity for me. So I want to present you with some Scala. I also know that DJUG is pretty damn smart, so I was thinking, how about we just jump right into something cool like functions and discuss how functional programming works in Scala and we can fill in some of the easy stuff as we go along. Then once we see how functions operate and Scala and remove any scariness that some may have, let’s dive into implicits and create some type classes, and show you why I think it is exciting and why I think we may see more of these in languages to come. My goal is to get you excited about that language and remove any concerns that you have for the language. As a prerequisite, I require you to get plenty of sleep since I will need some of your brain power.

About Daniel Hinojosa

Daniel Hinojosa is a programmer, consultant, instructor, speaker, and author. With over 20 years of experience, he does work for private, educational, and government institutions. Daniel loves JVM languages like Java, Groovy, and Scala; but also works with non-JVM languages like Haskell, Ruby, Python, LISP, C, C++. He is an avid Pomodoro Technique Practitioner and makes every attempt to learn a new programming language every year. Daniel is the author of Testing in Scala and video of Beginning Scala Programming Video Series for O’Reilly Publishing. For downtime, he enjoys reading, swimming, Legos, football, and cooking. You can find Dan on Twitter at @dhinojosa (https://twitter.com/dhinojosa).

7:45: Door Prizes

* IntelliJ IDE License (https://www.jetbrains.com/idea/)
* Pluralsight Subscription provided by DevelopIntelligence (http://www.developintelligence.com/)

8:00: After Meeting Networking

After meeting networking sponsored by Okta (https://developer.okta.com/). We meet at Ale House at Amato’s (2501 16th St, Denver, CO 80211).

Scheduled for Wednesday, April 10, 2019 – cancelled due to weather

5:30-6:00: Food, Soda, Beer and Networking

6:00-6:15: Announcements

6:15-7:45: Jamming with a Quantum Computer: A musical journey into quantum computing with James Weaver

Musical improvisation is the creative activity of composing music “in the moment” while performing it, often in a jam session with other musicians. Although composing and performing music is a creative process, the underlying musical style informs the probabilities of note and rhythmic choices that the musician makes. For example, when improvising in the style of twelve-bar blues, the notes played with the highest frequency of occurrence are typically the five that comprise the corresponding minor pentatonic scale.

This idea of musical style being a complex system of probabilities fits perfectly with the probabilistic nature of quantum mechanics, which is a phenomenon leveraged by quantum computing. To implement this idea, James Weaver created an open source application named Quantum Music Composer that makes use of a quantum computer to improvise music in a very simplified version of 17th century counterpoint.

In this session, James will give an introduction to quantum computing, cover a bit of music theory, and demonstrate how a quantum computer can compose music and participate in a musical jam session. He will then discuss the development and implementation of the Quantum Music Composer application on IBM, and Rigetti, quantum computers.

About James Weaver

James Weaver is a developer, author, and speaker with a passion for quantum computing. He is a Java Champion, and a JavaOne Rockstar. James has written books including Inside Java, Beginning J2EE, the Pro JavaFX series, and Java with Raspberry Pi. As an IBM Quantum Developer Advocate, James speaks internationally at quantum and classical computing conferences. He tweets as @JavaFXpert, and blogs at http://JavaFXpert.com and http://CulturedEar.com.

7:45: Door Prizes

* IntelliJ IDE License (https://www.jetbrains.com/idea/)
* Pluralsight Subscription provided by DevelopIntelligence (http://www.developintelligence.com/)

8:00: After Meeting Networking

After meeting networking sponsored by Okta (https://developer.okta.com/). We meet at Ale House at Amato’s (2501 16th St, Denver, CO 80211).

Scheduled for Wednesday, March 13, 2019 – cancelled due to weather

5:30-6:00: Food, Soda, Beer and Networking

6:00-6:15: Announcements

6:15-7:45: API/Webservice/REST Security

API’s are built on the foundation of the same technology that is used to build web applications. Therefore, many of the standard web security defenses will apply when building webservices. However, stateless and other specialized patterns make defending API’s different than normal web security in some regards. Access control, request forgery, session management, and other security layers, while familiar, often require different security designs in API’s. This module will review these needed security patterns as well as review a host of other specialized attacks and defenses that developers need to be aware of when building secure API’s.

About Jim Manico

Jim Manico is the founder of Manicode Security where he trains software developers on secure coding and security engineering. He is an investor/advisor for Signal Sciences and BitDiscovery. Jim is also a frequent speaker on secure software practices, is a member of the JavaOne rockstar speaker and Java Champion community and is the author of “Iron-Clad Java: Building Secure Web Applications” from McGraw-Hill and Oracle Press. Jim also volunteers for the OWASP foundation where he helps build application security standards and other documentation.

You can find Jim on Twitter at @manicode (https://twitter.com/manicode).

7:45: Door Prizes

* IntelliJ IDE License (https://www.jetbrains.com/idea/)
* Pluralsight Subscription provided by DevelopIntelligence (http://www.developintelligence.com/)

8:00: After Meeting Networking

After meeting networking sponsored by Okta (https://developer.okta.com/). We meet at Ale House at Amato’s (2501 16th St, Denver, CO 80211).

Wednesday, February 13, 2019

Details
5:30-6:00: Food, Soda, Beer and Networking

6:00-6:15: Announcements

6:15-7:45: Full Stack Reactive with Spring WebFlux and React

You have streaming data and want to expose it as reactive streams with Spring Boot. Great! Spring WebFlux makes that pretty easy. But what about the UI? Can you stream that data to the UI and have it be reactive and constantly updating too? This session explores techniques for making your app fully reactive with Spring WebFlux and React. Mostly live coding, with plenty of time for Q & A in the midst of it all.

About Josh Long

Josh (@starbuxman) is the Spring Developer Advocate at Pivotal. Josh is a Java Champion, author of 5 books (including O’Reilly’s Cloud Native Java: Designing Resilient Systems with Spring Boot, Spring Cloud, and Cloud Foundry) and numerous best-selling video trainings (including Building Microservices with Spring Boot Livelessons with Spring Boot co-founder Phil Webb), and an open-source contributor (Spring Boot, Spring Integration, Spring Cloud, Activiti and Vaadin).

About Matt Raible

Web Developer, Java Champion, and Developer Advocate at Okta with a passion for skiing, mountain biking, VWs, and good beer. Driving a ‘66 21-window and a ‘90 Syncro. Made in Montana. @mraible on Twitter.

7:45: Door Prizes

* IntelliJ IDE License (https://www.jetbrains.com/idea/)
* Pluralsight Subscription provided by DevelopIntelligence (http://www.developintelligence.com/)

8:00: After Meeting Networking

After meeting networking sponsored by Okta (https://developer.okta.com/). We meet at Ale House at Amato’s (2501 16th St, Denver, CO 80211).

Wednesday, January 9, 2019

Details

Wednesday, December 12, 2018

Hosted by Pivotal

Details

5:30-6:00: Food, Soda, Beer and Networking

6:00-6:15: Announcements

6:15-8:15: Lightning Talks!  

Talks for this meetup will be 10 minutes each, with a 5 minute transition period between them. These are in no particular order.

1. Principal Architect by David Ayers

Get Commit-Ted – A lightning talk about why writing your commit comments is as important as writing good, clean code

2. Parsing PDFs: From “Hello World” to Cease-and-Desist by Robin Howlett

How Apache PDFBox helped me get a meeting with the CEO of a $3B company

3. Restoring sanity to integration & functional testing with TestContainers by Benjamin Muschko

In this talk, we’ll have a look at setting up and running integration & functional tests with the help of the open source library TestContainers. You will learn how to stand up lightweight, disposable Docker instances running your application as reliable test fixtures.

4. Introduction to Apache Openwhisk serverless platform by Upkar Lidder

This will be a quick introduction to Serverless concepts including Actions and Triggers on the OpenWhisk Serverless open source platform. Apache OpenWhisk (Incubating) is an open source, distributed Serverless platform that executes functions (fx) in response to events at any scale. OpenWhisk manages the infrastructure, servers and scaling using Docker containers so you can focus on building amazing and efficient applications. Upkar Lidder is a Full Stack Developer and Data Wrangler with a decade of development experience in a variety of roles.

5. 10 minutes with GraphQL in Spring Boot by Butch Clark

Get an overview of how easy it is to implement a GraphQL interface in Spring Boot.

6. Bug Hunting with Git Bisect by Mike Kasberg

How to use git-bisect to pinpoint the cause of a bug.

7. Akka Streams – Moving and Transforming Data by Regina Peyfuss

Akka Streams is a library to process and transfer a sequence of elements using bounded buffer space. Translated to everyday terms it is possible to express a chain of processing entities, each executing independently (and possibly concurrently) from the others while only buffering a limited number of elements at any given time.

8. How NOT to Restore a VW Bus by Matt Raible

I restored a 1966 21-window VW Bus. It’s awesome, but the journey was long and painful.

8:15: Door Prizes and Ugly Sweater Contest