Templates listed here are not maintained by the play team, and so may be out of date.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. This project provides an implementation of akka s core akka actor module for scala. Akka is a opensource library or a toolkit written in scala to create concurrent, distributed and faulttolerant application. Anychart scalaakkamysql integration sample includes two parts.
Scale up concurrency scale out remoting fault tolerance. Beyond that, the akka actor library adds these additional benefits. For programming model, there is a big difference between the scala standard library and akka. Were also planning on updating and extending the material for akka 2. The documentation also warns that the ordering guarantee can be violated. In an sbt project, youve marked up your scala source code with scaladoc comments, and want to generate the api documentation for your project. An intuitive and safe way to do asynchronous, nonblocking backpressured stream processing. It seamlessly integrates features of objectoriented and functional languages. The purpose of this document is to guide users through the migration process and explain how to use the amk. The project structure mirrors that of upstream akka. The artima book actors in scala also covers the basics of akka, plus remoting. This project provides an implementation of akkas core akkaactor module for scala.
Scala is a pure objectoriented language in the sense that every value is an object. Akka is a toolkit for building highly concurrent, distributed, and resilient messagedriven applications for java and scala. Below is a code snippet of the library dependencies in your build. For an overview of the cluster support see the java and scala documentation chapters. The akkaactorjs project contains the core actor implementation. The timings are approximated and are still limited by the ceiling of the operating systems clock resolution. Whats the difference of the akkas actor with scalas actor. Play is based on a lightweight, stateless, webfriendly architecture and features predictable and minimal resource consumption cpu, memory, threads for highly. 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. Indepth documentation covering many of scalas features. An important goal is to minimize source differences between upstream akkaactor and akkaactorjs.
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. Akkas stm implements the concept in clojures stm view on state in general. Pay special attention to setting up the scala ide for eclipse optional. View message delivery reliability akka documentation. The api of akkas actors is similar to scala actors which has borrowed some of its syntax from erlang. You want to start an akka actor in a scala application, or attempt to control the start of an actor. Akka provides scalable realtime transaction processing. An indepth guide on how to write idiomatic scala code.
The akka actorjs project contains the core actor implementation. 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. Follow the instructions for setting up scala, sbt, giter8 etc. These allow you to create pipelines or streams that the result will travel through. 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. Net in your project, you can install it directly from nuget. Youre creating more complicated akka actors, and need to understand when the lifecycle methods on an actor are called.
An excellent stepbystep introduction to many of the scala features with the help of simple code examples. Akka uses the actor model to raise the abstraction level and provide a better platform to build correct concurrent and scalable applications. They use structural sharing and an insert or update does not ruin the old structure, hence persistent. Since akka is published to maven central for versions since 2.
A handy cheatsheet covering the basics of scala s syntax. Net distributed actor framework, run the following command in the package manager console. Scala reference manuals the scala programming language. Akka supports multiple programming models for concurrency, but it emphasizes actorbased concurrency, with inspiration drawn from erlang. A recent addition to akka s future is several monadic methods that are very similar to the ones used by scala s collections. Documentation faq download mailing list code commercial support message delivery reliability. This talk describes the techniques used for the hlist implementation in slick.
A futuret is simply something that will return a t in the future. 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. If you need a comprehensive and easy to follow manual for the scala language, the book programming in scala is the canonical reference text. 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. Software transactional memory scala akka documentation. For additional information, you can refer to the official akka documentation on akka clustering.
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. Main is not an argument, it is the launcher class i. Handson akka actor programming hassoplattnerinstitut. A model for concurrency and distribution without all the pain of threading primitives. The scala actor model, more specifically, akka, can help. 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. 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. In this case, as described in the documentation, it will set up the.
If you are new to akka just read along, but if you have used akka 0. In general, actors give you the benefit of offering a high level of abstraction for achieving concurrency and parallelism. As a reminder, we will be using the latest version of akka, which is 2. Enhance your akka systems with from the creators of akka, get technology enhancements, monitoring, and expert support with akka platform from lightbend. Akka is the implementation of the actor model on the jvm. Anychart scala akka mysql integration sample includes two parts. 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. A list of frequentlyasked questions about scala language features and their answers. Plugin documentation and other info, please look at live documents here. In this case, as described in the documentation, it will set up the actorsystem instance and other necessary infrastructure.
This guide introduces akka by describing the scala version of the hello world example. Before learning akka, you must have the basic knowledge of scala. An introduction to scalaakka actors actors and concurrency. Scala by example learn scala through a series of 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. Simple scala akka actor examples hello, world examples.
Do they need to be downloaded and installed separately, even though the scala ide plugin installed the rest of scala 2. Indepth documentation covering many of scala s features. Akka is a free and opensource toolkit and runtime simplifying the construction of concurrent and distributed applications on the jvm. Scala provides socalled persistent datastructures which makes working with immutable collections fast. 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. A handy cheatsheet covering the basics of scalas syntax. Slides pdf 20150318 reactive slick for database programming scaladays, san francisco, ca. More information is available in the documentation of the microkernel scala microkernel java. Most of the scala akka actor tutorials i see jump right into the deep end, throwing you into some tough concepts right away.
Jun 04, 2017 any plans to releasepublish the epub or pdf version of akka 2. The stm is based on transactional references referred to as refs. This is a grails plugin that enable the usage of akka actors both local and remote in grails web projects. 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. Any plans to releasepublish the epub or pdf version of akka 2. Akka is a toolkit and runtime for building highly concurrent, distributed, and faulttolerant eventdriven applications on the jvm.
1502 279 538 592 948 1542 256 347 602 1306 1481 697 967 603 372 911 418 1239 833 692 605 366 48 649 4 166 879 649 1609 182 1574 1059 1356 470 833 62 1262 561 1292 506 46 1295 234 898 1298 171 1026 417