Effective Akka

Avoid common mistakes when building distributed, asynchronous, high-performance software with the Akka toolkit and runtime. With this concise guide, author Jamie Allen provides a collection of best practices based on several years of using the actor model. The book also includes examples of actor application types and two primary patterns of actor usage, the Extra Pattern and Cameo Pattern. Allen, the Director of Consulting for Typesafe—creator of Akka and the Scala programming language—examines actors with a banking-service use case throughout the book, using examples shown in Akka and Scala. If you have any experience with Akka, this guide is essential. Delve into domain-driven and work-distribution actor applications Understand why it’s important to have actors do only one job Avoid thread blocking by allowing logic to be delegated to a Future Model interactions as simply as possible to avoid premature optimization Create well-defined interactions, and know exactly what failures can occur Learn why you should never treat actors as you would an ordinary class Keep track of what goes on in production by monitoring everything Tune Akka applications with the Typesafe Console

Avoid common mistakes when building distributed, asynchronous, high-performance software with the Akka toolkit and runtime. With this concise guide, author Jamie Allen provides a collection of best practices based on several years of using the actor model. The book also includes examples of actor application types and two primary patterns of actor usage, the Extra Pattern and Cameo Pattern. Allen, the Director of Consulting for Typesafe—creator of Akka and the Scala programming language—examines actors with a banking-service use case throughout the book, using examples shown in Akka and Scala. If you have any experience with Akka, this guide is essential. Delve into domain-driven and work-distribution actor applications Understand why it’s important to have actors do only one job Avoid thread blocking by allowing logic to be delegated to a Future Model interactions as simply as possible to avoid premature optimization Create well-defined interactions, and know exactly what failures can occur Learn why you should never treat actors as you would an ordinary class Keep track of what goes on in production by monitoring everything Tune Akka applications with the Typesafe Console

Annotation Avoid common mistakes when building distributed, asynchronous, high-performance software with the Akka toolkit and runtime. With this concise guide, author Jamie Allen provides a collection of best practices based on several years of using the actor model. The book also includes examples of actor application types and two primary patterns of actor usage, the Extra Pattern and Cameo Pattern. Allen, the Director of Consulting for Typesafecreator of Akka and the Scala programming languageexamines actors with a banking-service use case throughout the book, using examples shown in Akka and Scala. If you have any experience with Akka, this guide is essential. Delve into domain-driven and work-distribution actor applicationsUnderstand why its important to have actors do only one jobAvoid thread blocking by allowing logic to be delegated to a FutureModel interactions as simply as possible to avoid premature optimizationCreate well-defined interactions, and know exactly what failures can occurLearn why you should never treat actors as you would an ordinary classKeep track of what goes on in production by monitoring everythingTune Akka applications with the Typesafe Console.

When it comes to big data processing, we can no longer ignore concurrency or try to add it in after the fact. Fortunately, the solution is not a new paradigm of development, but rather an old one. With this hands-on guide, Java and Scala developers will learn how to embrace concurrent and distributed applications with the open source Akka toolkit. You’ll learn how to put the actor model and its associated patterns to immediate and practical use. Throughout the book, you’ll deal with an analogous workforce problem: how to schedule a group of people across a variety of projects while optimizing their time and skillsets. This example will help you understand how Akka uses actors, streams, and other tools to stitch your application together. Model software that reflects the real world with domain-driven design Learn principles and practices for implementing individual actors Unlock the real potential of Akka with patterns for combining multiple actors Understand the consistency tradeoffs in a distributed system Use several Akka methods for isolating and dealing with failures Explore ways to build systems that support availability and scalability Tune your Akka application for performance with JVM tools and dispatchers

Summary Reactive Design Patterns is a clearly written guide for building message-driven distributed systems that are resilient, responsive, and elastic. In this book you'll find patterns for messaging, flow control, resource management, and concurrency, along with practical issues like test-friendly designs. All patterns include concrete examples using Scala and Akka. Foreword by Jonas Bonér. Purchase of the print book includes a free eBook in PDF, Kindle, and ePub formats from Manning Publications. About the Technology Modern web applications serve potentially vast numbers of users - and they need to keep working as servers fail and new ones come online, users overwhelm limited resources, and information is distributed globally. A Reactive application adjusts to partial failures and varying loads, remaining responsive in an ever-changing distributed environment. The secret is message-driven architecture - and design patterns to organize it. About the Book Reactive Design Patterns presents the principles, patterns, and best practices of Reactive application design. You'll learn how to keep one slow component from bogging down others with the Circuit Breaker pattern, how to shepherd a many-staged transaction to completion with the Saga pattern, how to divide datasets by Sharding, and more. You'll even see how to keep your source code readable and the system testable despite many potential interactions and points of failure. What's Inside The definitive guide to the Reactive Manifesto Patterns for flow control, delimited consistency, fault tolerance, and much more Hard-won lessons about what doesn't work Architectures that scale under tremendous load About the Reader Most examples use Scala, Java, and Akka. Readers should be familiar with distributed systems. About the Author Dr. Roland Kuhn led the Akka team at Lightbend and coauthored the Reactive Manifesto. Brian Hanafee and Jamie Allen are experienced distributed systems architects. Table of Contents PART 1 - INTRODUCTION Why Reactive? A walk-through of the Reactive Manifesto Tools of the trade PART 2 - THE PHILOSOPHY IN A NUTSHELL Message passing Location transparency Divide and conquer Principled failure handling Delimited consistency Nondeterminism by need Message flow PART 3 - PATTERNS Testing reactive applications Fault tolerance and recovery patterns Replication patterns Resource-management patterns Message flow patterns Flow control patterns State management and persistence patterns

Summary Akka in Action is a comprehensive tutorial on building message-oriented systems using Akka. The book takes a hands-on approach, where each new concept is followed by an example that shows you how it works, how to implement the code, and how to (unit) test it. Purchase of the print book includes a free eBook in PDF, Kindle, and ePub formats from Manning Publications. About the Technology Akka makes it relatively easy to build applications in the cloud or on devices with many cores that efficiently use the full capacity of the computing power available. It's a toolkit that provides an actor programming model, a runtime, and required support tools for building scalable applications. About the Book Akka in Action shows you how to build message-oriented systems with Akka. This comprehensive, hands-on tutorial introduces each concept with a working example. You'll start with the big picture of how Akka works, and then quickly build and deploy a fully functional REST service out of actors. You'll explore test-driven development and deploying and scaling fault-tolerant systems. After mastering the basics, you'll discover how to model immutable messages, implement domain models, and apply techniques like event sourcing and CQRS. You'l also find a tutorial on building streaming applications using akka-stream and akka-http. Finally, you'l get practical advice on how to customize and extend your Akka system. What's Inside Getting concurrency right Testing and performance tuning Clustered and cloud-based applications Covers Akka version 2.4 About the Reader This book assumes that you're comfortable with Java and Scala. No prior experience with Akka required. About the Authors A software craftsman and architect, Raymond Roestenburg is an Akka committer. Rob Bakker specializes in concurrent back-end systems and systems integration. Rob Williams has more than 20 years of product development experience. Table of Contents Introducing Akka Up and running Test-driven development with actors Fault tolerance Futures Your first distributed Akka app Configuration, logging, and deployment Structural patterns for actors Routing messages Message channels Finite-state machines and agents System integration Streaming Clustering Actor persistence Performance tips Looking ahead

Get up to speed on Scala, the JVM language that offers all the benefits of a modern object model, functional programming, and an advanced type system. Packed with code examples, this comprehensive book shows you how to be productive with the language and ecosystem right away, and explains why Scala is ideal for today's highly scalable, data-centric applications that support concurrency and distribution. This second edition covers recent language features, with new chapters on pattern matching, comprehensions, and advanced functional programming. You’ll also learn about Scala’s command-line tools, third-party tools, libraries, and language-aware plugins for editors and IDEs. This book is ideal for beginning and advanced Scala developers alike. Program faster with Scala’s succinct and flexible syntax Dive into basic and advanced functional programming (FP) techniques Build killer big-data apps, using Scala’s functional combinators Use traits for mixin composition and pattern matching for data extraction Learn the sophisticated type system that combines FP and object-oriented programming concepts Explore Scala-specific concurrency tools, including Akka Understand how to develop rich domain-specific languages Learn good design techniques for building scalable and robust Scala applications

This book constitutes the thoroughly refereed post-conference proceedings of the 20th International Workshop on Multi-Agent-Based Simulation, MABS 2019, held in Montreal, QC, Canada, in May 2019 as part of the AAMAS 2019, the 18th International Conference on Autonomous Agents and Multiagent Systems. The 9 revised full papers included in this volume were carefully selected from 15 submissions. They focus on finding efficient solutions to model complex social systems in such areas as economics, management, and organisational and social sciences. In all these areas, agent theories, metaphors, models, analysis, experimental designs, empirical studies, and methodological principles, converge into simulation as a way of achieving explanations and predictions, exploration and testing of hypotheses, better designs and systems.