Microservices Expo Authors: David Sprott, Sematext Blog, Lori MacVittie, Yeshim Deniz, Carmen Gonzalez

Related Topics: Microservices Expo, Java IoT, Industrial IoT, Microsoft Cloud, Agile Computing, Cloud Security

Microservices Expo: Book Review

Book Review: Implementing Domain-Driven Design

Will take your skills to the next level

Agile is not easy and implementing Domain-Driven Design (DDD) is not easy. I think my favorite part of the book is that the author realizes that, and also has a realistic perspective on what it takes to successfully use agile processes and DDD.

The book starts out with a really nice overview of DDD. By the time you are done the first chapter you have a pretty good high level picture of what DDD is all about. One topic he really drives home is Ubiquitous Language.

Ubiquitous Language is a shared team language that defines a certain domain. When you are reading about Ubiquitous Language it may seem like something that just happens on its own. It isn't. An explicit domain language should be defined, it should not just be allowed to implicitly come about. This same concept has been around for years in Water Fall, Unified Process, RUP, and other processes. It has always been a very important part of the software development process, so don't discount it.

Chapter 1 also does a great job of providing tips on how to show the business value of using DDD. The author has a clear understanding that without the support of the business you aren't going to get very far with your project, and in order to get them onboard you need to show them what they will gain by supporting DDD.

The remaining chapters dig into the details of DDD. I have listed the chapters below. Their titles are pretty self-explanatory.

Chapter 1. Getting Started with DDD
Chapter 2. Domains, Subdomains, and Bounded Contexts
Chapter 3. Context Maps
Chapter 4. Architecture
Chapter 5. Entities
Chapter 6. Value Objects
Chapter 7. Services
Chapter 8. Domain Events
Chapter 9. Modules
Chapter 10. Aggregates
Chapter 11. Factories
Chapter 12. Repositories
Chapter 13. Integrating Bounded Contexts
Chapter 14. Application
Appendix A. Aggregates and Event Sourcing: A+ES

I have seen a lot of teams that could not build software with UP or RUP adopt Scrum in hopes that changing the process will make a difference. It never does. There are a variety of reasons including not doing any architecture, not having experienced developers with the right skill sets, not having the right business users involved, not having the requirements elicitation skills needed, and the list can go on and on. The author clearly understands Scrum is not a silver bullet. I mention this because DDD done correctly can give agile processes a much better chance at success, but you must have the skills on the team in order pull it off.

I was really glad to see the author included a chapter on architecture. The author does a great job of covering a ton of architectural styles and patterns. Patterns, styles, and topic found in the Architecture chapter include Layers Architecture with the Dependency Inversion Principle, Hexagonal Architecture, SOA environment, REST, Data Fabric, Grid-Based Distributed Cache, and CQRS.

Every chapter is an in depth look at the topic of the given chapter. I did not leave any of the chapters feeling like I missed something. I have read both Domain-Driven Design: Tackling Complexity in the Heart of Software and Patterns of Enterprise Application Architecture, and I had both handy for looking up references to them. It is not necessary to read them first, but it did help that I had.

I am not going to say using DDD is easy, but I will say this book can definitely get you to where you can successfully use it. The author's writing style is really good and he is good at making the book entertaining. I will however say this, be prepared to read the entire book if you want to get to that point of successfully using DDD. There is a lot to learn, but it is worth it.

I highly recommend this book to every software architect and developer. Even if you don't go all out DDD there is a ton of great advice and wisdom found in this book that will help you improve your skills.

Implementing Domain-Driven Design

More Stories By Tad Anderson

Tad Anderson has been doing Software Architecture for 18 years and Enterprise Architecture for the past few.

@MicroservicesExpo Stories
In many organizations governance is still practiced by phase or stage gate peer review, and Agile projects are forced to accommodate, which leads to WaterScrumFall or worse. But governance criteria and policies are often very weak anyway, out of date or non-existent. Consequently governance is frequently a matter of opinion and experience, highly dependent upon the experience of individual reviewers. As we all know, a basic principle of Agile methods is delegation of responsibility, and ideally ...
Monitoring of Docker environments is challenging. Why? Because each container typically runs a single process, has its own environment, utilizes virtual networks, or has various methods of managing storage. Traditional monitoring solutions take metrics from each server and applications they run. These servers and applications running on them are typically very static, with very long uptimes. Docker deployments are different: a set of containers may run many applications, all sharing the resource...
When we talk about the impact of BYOD and BYOA and the Internet of Things, we often focus on the impact on data center architectures. That's because there will be an increasing need for authentication, for access control, for security, for application delivery as the number of potential endpoints (clients, devices, things) increases. That means scale in the data center. What we gloss over, what we skip, is that before any of these "things" ever makes a request to access an application it had to...
Virgil consists of an open-source encryption library, which implements Cryptographic Message Syntax (CMS) and Elliptic Curve Integrated Encryption Scheme (ECIES) (including RSA schema), a Key Management API, and a cloud-based Key Management Service (Virgil Keys). The Virgil Keys Service consists of a public key service and a private key escrow service. 

The best way to leverage your Cloud Expo presence as a sponsor and exhibitor is to plan your news announcements around our events. The press covering Cloud Expo and @ThingsExpo will have access to these releases and will amplify your news announcements. More than two dozen Cloud companies either set deals at our shows or have announced their mergers and acquisitions at Cloud Expo. Product announcements during our show provide your company with the most reach through our targeted audiences.
In his general session at 19th Cloud Expo, Manish Dixit, VP of Product and Engineering at Dice, will discuss how Dice leverages data insights and tools to help both tech professionals and recruiters better understand how skills relate to each other and which skills are in high demand using interactive visualizations and salary indicator tools to maximize earning potential. Manish Dixit is VP of Product and Engineering at Dice. As the leader of the Product, Engineering and Data Sciences team a...
SYS-CON Events announced today that eCube Systems, the leading provider of modern development tools and best practices for Continuous Integration on OpenVMS, will exhibit at SYS-CON's @DevOpsSummit at Cloud Expo New York, which will take place on June 7-9, 2016, at the Javits Center in New York City, NY. eCube Systems offers a family of middleware products and development tools that maximize return on technology investment by leveraging existing technical equity to meet evolving business needs. ...
Join Impiger for their featured webinar: ‘Cloud Computing: A Roadmap to Modern Software Delivery’ on November 10, 2016, at 12:00 pm CST. Very few companies have not experienced some impact to their IT delivery due to the evolution of cloud computing. This webinar is not about deciding whether you should entertain moving some or all of your IT to the cloud, but rather, a detailed look under the hood to help IT professionals understand how cloud adoption has evolved and what trends will impact th...
As we enter the final week before the 19th International Cloud Expo | @ThingsExpo in Santa Clara, CA, it's time for me to reflect on six big topics that will be important during the show. Hybrid Cloud This general-purpose term seems to provide a comfort zone for many enterprise IT managers. It sounds reassuring to be able to work with one of the major public-cloud providers like AWS or Microsoft Azure while still maintaining an on-site presence.
operations aren’t merging to become one discipline. Nor is operations simply going away. Rather, DevOps is leading software development and operations – together with other practices such as security – to collaborate and coexist with less overhead and conflict than in the past. In his session at @DevOpsSummit at 19th Cloud Expo, Gordon Haff, Red Hat Technology Evangelist, will discuss what modern operational practices look like in a world in which applications are more loosely coupled, are deve...
All clouds are not equal. To succeed in a DevOps context, organizations should plan to develop/deploy apps across a choice of on-premise and public clouds simultaneously depending on the business needs. This is where the concept of the Lean Cloud comes in - resting on the idea that you often need to relocate your app modules over their life cycles for both innovation and operational efficiency in the cloud. In his session at @DevOpsSummit at19th Cloud Expo, Valentin (Val) Bercovici, CTO of So...
DevOps is a term that comes full of controversy. A lot of people are on the bandwagon, while others are waiting for the term to jump the shark, and eventually go back to business as usual. Regardless of where you are along the specturm of loving or hating the term DevOps, one thing is certain. More and more people are using it to describe a system administrator who uses scripts, or tools like, Chef, Puppet or Ansible, in order to provision infrastructure. There is also usually an expectation of...
DevOps is speeding towards the IT world like a freight train and the hype around it is deafening. There is no reason to be afraid of this change as it is the natural reaction to the agile movement that revolutionized development just a few years ago. By definition, DevOps is the natural alignment of IT performance to business profitability. The relevance of this has yet to be quantified but it has been suggested that the route to the CEO’s chair will come from the IT leaders that successfully ma...
DevOps is being widely accepted (if not fully adopted) as essential in enterprise IT. But as Enterprise DevOps gains maturity, expands scope, and increases velocity, the need for data-driven decisions across teams becomes more acute. DevOps teams in any modern business must wrangle the ‘digital exhaust’ from the delivery toolchain, "pervasive" and "cognitive" computing, APIs and services, mobile devices and applications, the Internet of Things, and now even blockchain. In this power panel at @...
As software becomes more and more complex, we, as software developers, have been splitting up our code into smaller and smaller components. This is also true for the environment in which we run our code: going from bare metal, to VMs to the modern-day Cloud Native world of containers, schedulers and microservices. While we have figured out how to run containerized applications in the cloud using schedulers, we've yet to come up with a good solution to bridge the gap between getting your conta...
19th Cloud Expo, taking place November 1-3, 2016, at the Santa Clara Convention Center in Santa Clara, CA, will feature technical sessions from a rock star conference faculty and the leading industry players in the world. Cloud computing is now being embraced by a majority of enterprises of all sizes. Yesterday's debate about public vs. private has transformed into the reality of hybrid cloud: a recent survey shows that 74% of enterprises have a hybrid cloud strategy. Meanwhile, 94% of enterpri...
This is a no-hype, pragmatic post about why I think you should consider architecting your next project the way SOA and/or microservices suggest. No matter if it’s a greenfield approach or if you’re in dire need of refactoring. Please note: considering still keeps open the option of not taking that approach. After reading this, you will have a better idea about whether building multiple small components instead of a single, large component makes sense for your project. This post assumes that you...
Without lifecycle traceability and visibility across the tool chain, stakeholders from Planning-to-Ops have limited insight and answers to who, what, when, why and how across the DevOps lifecycle. This impacts the ability to deliver high quality software at the needed velocity to drive positive business outcomes. In his general session at @DevOpsSummit at 19th Cloud Expo, Eric Robertson, General Manager at CollabNet, will discuss how customers are able to achieve a level of transparency that e...
DevOps theory promotes a culture of continuous improvement built on collaboration, empowerment, systems thinking, and feedback loops. But how do you collaborate effectively across the traditional silos? How can you make decisions without system-wide visibility? How can you see the whole system when it is spread across teams and locations? How do you close feedback loops across teams and activities delivering complex multi-tier, cloud, container, serverless, and/or API-based services?
Today every business relies on software to drive the innovation necessary for a competitive edge in the Application Economy. This is why collaboration between development and operations, or DevOps, has become IT’s number one priority. Whether you are in Dev or Ops, understanding how to implement a DevOps strategy can deliver faster development cycles, improved software quality, reduced deployment times and overall better experiences for your customers.