/akira

Learning Scala, Play and Akka

Primary LanguageScala

Akira

Akira

Goal

Sample application to learn the following technologies:

  • Play:
    • SBT configuration and plugins
    • Dependency Injection
    • Actions, Controllers, and Results
    • Assets management
    • Templates, Forms and Bootstrap
    • Session management, authentication and Silhouette
    • Concurrency:
      • Asynchronous vs. synchronous:
        • Blocking vs non-blocking
      • Execution contexts and Thread pools:
        • Work stealing (ForkJoin)
        • Asynchronous Actions and thread pools
    • Database access, Slick and PostgreSQL
    • Akka streams and WebSockets
  • Akka:
    • Isolated mutability, Messages and Actors
    • Actor System
    • Dispatcher

Prerequisites

Scala basic knowledge:

  • Classes:
    • Standard, abstract, case, trait
    • Companion object
    • Parameters, main and auxiliary constructor
    • Visibility
    • Type parametrization
  • Function and methods:
    • Function object (functor), Apply and FunctionN trait
    • Function literals
    • Methods and difference with Function Objects
    • Partial function, Partial application, Currying and Closures
    • Syntactic sugar for function/methods with one parameter:
      • Curly braces, white space
    • Repeated parameters, default values and implicits
  • Basic types
  • String interpolation
  • Pattern matching and case classes
  • For comprehension:
    • Map, filter, foreach, flatMap, foldLeft, foldRight
  • Options
  • Lazy instantiation
  • Concurrency with Futures and Promises

How to start

To start the application:

  • SBT:
    • Install SBT:
  • Github:
  • PostgreSQL database:
    • Create database and needed tables:
      • Run 'conf/db/postgresql/create.sql'
        • Explained at: conf/db/postgresql/README.md
  • Aplication configuration:
    • In 'conf/application.conf' change the string 'XXX' by your server domain/IP
    • In 'conf/application.conf' change the string '*** CHANGE IT ***' by your key
    • In 'conf/silhouette.conf' change the strings '*** CHANGE IT ***' by your keys
  • Client Javascript:
    • The application is using IpInfo service to get your client current location:
      • In 'app/assets/javascripts/client.js' change the string 'XXX' by your token
  • Run the application:
    • Run 'sbt', and once in the sbt console, run 'runProd'