Domain Modeling Made Functional

You want increased customer satisfaction, faster development cycles, and less wasted work. Domain-driven design (DDD) combined with functional programming is the innovative combo that will get you there. In this pragmatic, down-to-earth guide, you'll see how applying the core principles of functional programming can result in software designs that model real-world requirements both elegantly and concisely - often more so than an object-oriented approach. Practical examples in the open-source F# functional language, and examples from familiar business domains, show you how to apply these techniques to build software that is business-focused, flexible, and high quality. Domain-driven design is a well-established approach to designing software that ensures that domain experts and developers work together effectively to create high-quality software. This book is the first to combine DDD with techniques from statically typed functional programming. This book is perfect for newcomers to DDD or functional programming - all the techniques you need will be introduced and explained. Model a complex domain accurately using the F# type system, creating compilable code that is also readable documentation---ensuring that the code and design never get out of sync. Encode business rules in the design so that you have "compile-time unit tests," and eliminate many potential bugs by making illegal states unrepresentable. Assemble a series of small, testable functions into a complete use case, and compose these individual scenarios into a large-scale design. Discover why the combination of functional programming and DDD leads naturally to service-oriented and hexagonal architectures. Finally, create a functional domain model that works with traditional databases, NoSQL, and event stores, and safely expose your domain via a website or API. Solve real problems by focusing on real-world requirements for your software. What You Need: The code in this book is designed to be run interactively on Windows, Mac and Linux.You will need a recent version of F# (4.0 or greater), and the appropriate .NET runtime for your platform.Full installation instructions for all platforms at fsharp.org.

Summary Get Programming with F#: A guide for .NET developers teaches F# through 43 example-based lessons with built-in exercises so you can learn the only way that really works: by practicing. The book upgrades your .NET skills with a touch of functional programming in F#. You'll pick up core FP principles and learn techniques for iron-clad reliability and crystal clarity. You'll discover productivity techniques for coding F# in Visual Studio, functional design, and integrating functional and OO code. Purchase of the print book includes a free eBook in PDF, Kindle, and ePub formats from Manning Publications. About the Technology Your .NET applications need to be good for the long haul. F#'s unique blend of functional and imperative programming is perfect for writing code that performs flawlessly now and keeps running as your needs grow and change. It takes a little practice to master F#'s functional-first style, so you may as well get programming! What's Inside Learn how to write bug-free programs Turn tedious common tasks into quick and easy ones Use minimal code to work with JSON, CSV, XML, and HTML data Integrate F# with your existing C# and VB.NET applications Create web-enabled applications About the Reader Written for intermediate C# and Visual Basic .NET developers. No experience with F# is assumed. Table of Contents Unit 1 - F# AND VISUAL STUDIO Lesson 1 - The Visual Studio experience Lesson 2 - Creating your first F# program Lesson 3 - The REPL-changing how we develop Unit 2 - HELLO F# Lesson 4 - Saying a little, doing a lot Lesson 5 - Trusting the compiler Lesson 6 - Working with immutable data Lesson 7 - Expressions and statements Lesson 8 Capstone 1 Unit 3 - TYPES AND FUNCTIONS Lesson 9 - Shaping data with tuples Lesson 10 - Shaping data with records Lesson 11 - Building composable functions Lesson 12 - Organizing code without classes Lesson 13 - Achieving code reuse in F# Lesson 14 - Capstone 2 Unit 4 - COLLECTIONS IN F# Lesson 15 - Working with collections in F# Lesson 16 - Useful collection functions Lesson 17 - Maps, dictionaries, and sets Lesson 18 - Folding your way to success Lesson 19 - Capstone 3 Unit 5 - THE PIT OF SUCCESS WITH THE F# TYPE SYSTEM Lesson 20 - Program flow in F# Lesson 21 - Modeling relationships in F# Lesson 22 - Fixing the billion-dollar mistake Lesson 23 - Business rules as code Lesson 24 - Capstone 4 Unit 6 - LIVING ON THE .NET PLATFORM Lesson 25 - Consuming C# from F# Lesson 26 - Working with NuGet packages Lesson 27 - Exposing F# types and functionsto C# Lesson 28 - Architecting hybrid language applications Lesson 29 - Capstone 5 Unit 7 - WORKING WITH DATA Lesson 30 - Introducing type providers Lesson 31 - Building schemas from live data Lesson 32 - Working with SQL Lesson 33 - Creating type provider-backed APIs Lesson 34 - Using type providers in the real world Lesson 35 - Capstone 6 Unit 8 - WEB PROGRAMMING Lesson 36 - Asynchronous workflows Lesson 37 - Exposing data over HTTP Lesson 38 - Consuming HTTP data Lesson 39 - Capstone 7 Unit 9 - UNIT TESTING Lesson 40 - Unit testing in F# Lesson 41 - Property-based testing in F# Lesson 42 - Web testing Lesson 43 - Capstone 8 Unit 10 - WHERE NEXT? Appendix A - The F# community Appendix B - F# in my organization Appendix C - Must-visit F# resources Appendix D - Must-have F# libraries Appendix E - Other F# language feature

Summary Functional and Reactive Domain Modeling teaches you how to think of the domain model in terms of pure functions and how to compose them to build larger abstractions. Purchase of the print book includes a free eBook in PDF, Kindle, and ePub formats from Manning Publications. About the Technology Traditional distributed applications won't cut it in the reactive world of microservices, fast data, and sensor networks. To capture their dynamic relationships and dependencies, these systems require a different approach to domain modeling. A domain model composed of pure functions is a more natural way of representing a process in a reactive system, and it maps directly onto technologies and patterns like Akka, CQRS, and event sourcing. About the Book Functional and Reactive Domain Modeling teaches you consistent, repeatable techniques for building domain models in reactive systems. This book reviews the relevant concepts of FP and reactive architectures and then methodically introduces this new approach to domain modeling. As you read, you'll learn where and how to apply it, even if your systems aren't purely reactive or functional. An expert blend of theory and practice, this book presents strong examples you'll return to again and again as you apply these principles to your own projects. What's Inside Real-world libraries and frameworks Establish meaningful reliability guarantees Isolate domain logic from side effects Introduction to reactive design patterns About the Reader Readers should be comfortable with functional programming and traditional domain modeling. Examples use the Scala language. About the Author Software architect Debasish Ghosh was an early adopter of reactive design using Scala and Akka. He's the author of DSLs in Action, published by Manning in 2010. Table of Contents Functional domain modeling: an introduction Scala for functional domain models Designing functional domain models Functional patterns for domain models Modularization of domain models Being reactive Modeling with reactive streams Reactive persistence and event sourcing Testing your domain model Summary - core thoughts and principles

"Domain-Driven Design" incorporates numerous examples in Java-case studies taken from actual projects that illustrate the application of domain-driven design to real-world software development.

Distributed across servers, difficult to test, and resistant to modification--modern software is complex. Grokking Simplicity is a friendly, practical guide that will change the way you approach software design and development. It introduces a unique approach to functional programming that explains why certain features of software are prone to complexity, and teaches you the functional techniques you can use to simplify these systems so that they''re easier to test and debug. Available in PDF (ePub, kindle, and liveBook formats coming soon). about the technology Even experienced developers struggle with software systems that sprawl across distributed servers and APIs, are filled with redundant code, and are difficult to reliably test and modify. Adopting ways of thinking derived from functional programming can help you design and refactor your codebase in ways that reduce complexity, rather than encouraging it. Grokking Simplicity lays out how to use functional programming in a professional environment to write a codebase that''s easier to test and reuse, has fewer bugs, and is better at handling the asynchronous nature of distributed systems. about the book In Grokking Simplicity, you''ll learn techniques and, more importantly, a mindset that will help you tackle common problems that arise when software gets complex. Veteran functional programmer Eric Normand guides you to a crystal-clear understanding of why certain features of modern software are so prone to complexity and introduces you to the functional techniques you can use to simplify these systems so that they''re easier to read, test, and debug. Through hands-on examples, exercises, and numerous self-assessments, you''ll learn to organize your code for maximum reusability and internalize methods to keep unwanted complexity out of your codebase. Regardless of the language you''re using, the ways of thinking in this book will help recognize problematic code and tame even the most complex software. what''s inside Apply functional programming principles to reduce codebase complexity Work with data transformation pipelines for code that''s easier to test and reuse Tools for modeling time to simplify asynchrony 60 exercises and 100 questions to test your knowledge about the reader For experienced programmers. Examples are in JavaScript. about the author Eric Normand has been a functional programmer since 2001 and has been teaching functional programming online and in person since 2007. Visit LispCast.com to see more of his credentials.

Summary Secure by Design teaches developers how to use design to drive security in software development. This book is full of patterns, best practices, and mindsets that you can directly apply to your real world development. You'll also learn to spot weaknesses in legacy code and how to address them. About the technology Security should be the natural outcome of your development process. As applications increase in complexity, it becomes more important to bake security-mindedness into every step. The secure-by-design approach teaches best practices to implement essential software features using design as the primary driver for security. About the book Secure by Design teaches you principles and best practices for writing highly secure software. At the code level, you’ll discover security-promoting constructs like safe error handling, secure validation, and domain primitives. You’ll also master security-centric techniques you can apply throughout your build-test-deploy pipeline, including the unique concerns of modern microservices and cloud-native designs. What's inside Secure-by-design concepts Spotting hidden security problems Secure code constructs Assessing security by identifying common design flaws Securing legacy and microservices architectures About the reader Readers should have some experience in designing applications in Java, C#, .NET, or a similar language. About the author Dan Bergh Johnsson, Daniel Deogun, and Daniel Sawano are acclaimed speakers who often present at international conferences on topics of high-quality development, as well as security and design.

“For software developers of all experience levels looking to improve their results, and design and implement domain-driven enterprise applications consistently with the best current state of professional practice, Implementing Domain-Driven Design will impart a treasure trove of knowledge hard won within the DDD and enterprise application architecture communities over the last couple decades.” –Randy Stafford, Architect At-Large, Oracle Coherence Product Development “This book is a must-read for anybody looking to put DDD into practice.” –Udi Dahan, Founder of NServiceBus Implementing Domain-Driven Design presents a top-down approach to understanding domain-driven design (DDD) in a way that fluently connects strategic patterns to fundamental tactical programming tools. Vaughn Vernon couples guided approaches to implementation with modern architectures, highlighting the importance and value of focusing on the business domain while balancing technical considerations. Building on Eric Evans’ seminal book, Domain-Driven Design, the author presents practical DDD techniques through examples from familiar domains. Each principle is backed up by realistic Java examples–all applicable to C# developers–and all content is tied together by a single case study: the delivery of a large-scale Scrum-based SaaS system for a multitenant environment. The author takes you far beyond “DDD-lite” approaches that embrace DDD solely as a technical toolset, and shows you how to fully leverage DDD’s “strategic design patterns” using Bounded Context, Context Maps, and the Ubiquitous Language. Using these techniques and examples, you can reduce time to market and improve quality, as you build software that is more flexible, more scalable, and more tightly aligned to business goals. Coverage includes Getting started the right way with DDD, so you can rapidly gain value from it Using DDD within diverse architectures, including Hexagonal, SOA, REST, CQRS, Event-Driven, and Fabric/Grid-Based Appropriately designing and applying Entities–and learning when to use Value Objects instead Mastering DDD’s powerful new Domain Events technique Designing Repositories for ORM, NoSQL, and other databases

Summary The Joy of Clojure, Second Edition is a deep look at the Clojure language. Fully updated for Clojure 1.6, this new edition goes beyond just syntax to show you the "why" of Clojure and how to write fluent Clojure code. You'll learn functional and declarative approaches to programming and will master the techniques that make Clojure so elegant and efficient. Purchase of the print book includes a free eBook in PDF, Kindle, and ePub formats from Manning Publications. About the Technology The Clojure programming language is a dialect of Lisp that runs on the Java Virtual Machine and JavaScript runtimes. It is a functional programming language that offers great performance, expressive power, and stability by design. It gives you built-in concurrency and the predictable precision of immutable and persistent data structures. And it's really, really fast. The instant you see long blocks of Java or Ruby dissolve into a few lines of Clojure, you'll know why the authors of this book call it a "joyful language." It's no wonder that enterprises like Staples are betting their infrastructure on Clojure. About the Book The Joy of Clojure, Second Edition is a deep account of the Clojure language. Fully updated for Clojure 1.6, this new edition goes beyond the syntax to show you how to write fluent Clojure code. You'll learn functional and declarative approaches to programming and will master techniques that make Clojure elegant and efficient. The book shows you how to solve hard problems related to concurrency, interoperability, and performance, and how great it can be to think in the Clojure way. Appropriate for readers with some experience using Clojure or common Lisp. What's Inside Build web apps using ClojureScript Master functional programming techniques Simplify concurrency Covers Clojure 1.6 About the Authors Michael Fogus and Chris Houser are contributors to the Clojure and ClojureScript programming languages and the authors of various Clojure libraries and language features. Table of Contents PART 1 FOUNDATIONS Clojure philosophy Drinking from the Clojure fire hose Dipping your toes in the pool PART 2 DATA TYPES On scalars Collection types PART 3 FUNCTIONAL PROGRAMMING Being lazy and set in your ways Functional programming PART 4 LARGE-SCALE DESIGN Macros Combining data and code Mutation and concurrency Parallelism PART 5 HOST SYMBIOSIS Java.next Why ClojureScript? PART 6 TANGENTIAL CONSIDERATIONS Data-oriented programming Performance Thinking programs Clojure changes the way you think