Slides pdf 20150318 reactive slick for database programming scaladays, san francisco, ca. This will take you through how to use the typesafe templates to get an akka project set up just like you were used to in the coursera class. A handy cheatsheet covering the basics of scalas syntax. If you need a comprehensive and easy to follow manual for the scala language, the book programming in scala is the canonical reference text.
This is a grails plugin that enable the usage of akka actors both local and remote in grails web projects. The akka actorjs project contains the core actor implementation. Most of the scala akka actor tutorials i see jump right into the deep end, throwing you into some tough concepts right away. Do they need to be downloaded and installed separately, even though the scala ide plugin installed the rest of scala 2. Akka provides scalable realtime transaction processing. Scale up concurrency scale out remoting fault tolerance. The artima book actors in scala also covers the basics of akka, plus remoting. In the scala standard library, you basically implement the run method and if you want to wait for an incoming message, you get yourself into a. Beyond that, the akka actor library adds these additional benefits. In this case, as described in the documentation, it will set up the actorsystem instance and other necessary infrastructure. The documentation also warns that the ordering guarantee can be violated. Net in your project, you can install it directly from nuget.
In this case, as described in the documentation, it will set up the. Jun 04, 2017 any plans to releasepublish the epub or pdf version of akka 2. All you need to run a future, is to have an implicit executioncontext, which you can derive from a java executor service. Youre creating more complicated akka actors, and need to understand when the lifecycle methods on an actor are called. Whats the difference of the akkas actor with scalas actor. Scala is a pure objectoriented language in the sense that every value is an object.
The project structure mirrors that of upstream akka. Scala is a modern multiparadigm programming language designed to express common programming patterns in a concise, elegant, and typesafe way. Simple scala akka actor examples hello, world examples. This talk describes the techniques used for the hlist implementation in slick. An intuitive and safe way to do asynchronous, nonblocking backpressured stream processing.
Akka is a opensource library or a toolkit written in scala to create concurrent, distributed and faulttolerant application. The stm is based on transactional references referred to as refs. They are a part of akka open source library, and i think in the future will be a part of the scala standard library as well. Scala reference manuals the scala programming language.
This is an excerpt from the scala cookbook partially modified for the internet. Indepth documentation covering many of scala s features. Anychart scala akka mysql integration sample includes two parts. An introduction to scalaakka actors actors and concurrency.
Understanding the methods in the scalaakka actor lifecycle. Before learning akka, you must have the basic knowledge of scala. Akka is a toolkit and runtime for building highly concurrent, distributed, and faulttolerant eventdriven applications on the jvm. They use structural sharing and an insert or update does not ruin the old structure, hence persistent. Follow the instructions for setting up scala, sbt, giter8 etc. This guide introduces akka by describing the scala version of the hello world example. An indepth guide on how to write idiomatic scala code. Type activator new in cmdterminal you can choose 4 because hello world example is based on scala import the project to your favorite ide and start with the hello world example. Software transactional memory scala akka documentation.
Indepth documentation covering many of scalas features. Any plans to releasepublish the epub or pdf version of akka 2. Scala provides socalled persistent datastructures which makes working with immutable collections fast. If you are new to akka just read along, but if you have used akka 0. Below is a code snippet of the library dependencies in your build. An important goal is to minimize source differences between upstream akka actor and akka actorjs. Play is based on a lightweight, stateless, webfriendly architecture and features predictable and minimal resource consumption cpu, memory, threads for highly. An important goal is to minimize source differences between upstream akkaactor and akkaactorjs. This project provides an implementation of akkas core akkaactor module for scala. You want to start an akka actor in a scala application, or attempt to control the start of an actor.
A list of frequentlyasked questions about scala language features and their answers. Personally im more into the crawl before you walk approach, and to that end, here are some simple akka actor examples, of hello, world variety. In this blog post, sidharth khattri explains the process wherein you can stream data directly from postgresql database using scala slick which is scalas database accessquery library and akka streams. For programming model, there is a big difference between the scala standard library and akka. Pay special attention to setting up the scala ide for eclipse optional. Main is not an argument, it is the launcher class i. Were also planning on updating and extending the material for akka 2. It seamlessly integrates features of objectoriented and functional languages. The play community also has a number of tutorials and templates that cover aspects of play than the documentation can, or has a different angle. A model for concurrency and distribution without all the pain of threading primitives.
More information is available in the documentation of the microkernel scala microkernel java. Akka uses the actor model to raise the abstraction level and provide a better platform to build correct concurrent and scalable applications. A recent addition to akkas future is several monadic methods that are very similar to the. This project provides an implementation of akka s core akka actor module for scala. In the scala standard library, you basically implement the run method and if you want to wait for an incoming message, you get yourself into a waiting state by calling receive or react.
The purpose of this document is to guide users through the migration process and explain how to use the amk. Scala sbt documentation in pdf format pdf file it took a lot of manual effort to turn the online documentation into 65 pages of a readable pdf doc, so i dont have any plans to update this as time goes on, but as mentioned, for the current date, its accurate. Plugin documentation and other info, please look at live documents here. Handson akka actor programming hassoplattnerinstitut. A futuret is simply something that will return a t in the future. Net distributed actor framework, run the following command in the package manager console. For an overview of the cluster support see the java and scala documentation chapters. Akka is a free and opensource toolkit and runtime simplifying the construction of concurrent and distributed applications on the jvm. Anychart scalaakkamysql integration sample includes two parts. Enhance your akka systems with from the creators of akka, get technology enhancements, monitoring, and expert support with akka platform from lightbend.
Akka supports multiple programming models for concurrency, but it emphasizes actorbased concurrency, with inspiration drawn from erlang. Scala by example learn scala through a series of examples. An excellent stepbystep introduction to many of the scala features with the help of simple code examples. Please take the time to read this excellent document and view this presentation by rich hickey the genius behind clojure, since it forms the basis of akkas view on stm and state in general. When i look at my scala projects properties, i indeed do not see any of the akka jar files that are mentioned in the akka documentation. Akka is the implementation of the actor model on the jvm.
The timings are approximated and are still limited by the ceiling of the operating systems clock resolution. Documentation faq download mailing list code commercial support message delivery reliability. Templates listed here are not maintained by the play team, and so may be out of date. Streaming data from postgresql using akka streams and slick in play framework. Since akka is published to maven central for versions since 2. The akkaactorjs project contains the core actor implementation. For faulttolerance it adopts the let it crash model, which has been used with great success in the telecoms industry to build applications that selfheal systems that never stop. Our akka tutorial includes all topics of akka api such as what is actor, actor life cycle, actors communication, props, child actor, actor system etc. Akkas stm implements the concept in clojures stm view on state in general. In general, actors give you the benefit of offering a high level of abstraction for achieving concurrency and parallelism. The scala actor model, more specifically, akka, can help. The api of akkas actors is similar to scala actors which has borrowed some of its syntax from erlang. These allow you to create pipelines or streams that the result will travel through. A handy cheatsheet covering the basics of scala s syntax.
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