Building Akka
This page describes how to build and run Akka from the latest source code.
§Get the Source Code
Akka uses Git and is hosted at Github.
You first need Git installed on your machine. You can then clone the source repository from http://github.com/akka/akka.
For example:
- git clone git://github.com/akka/akka.git
If you have already cloned the repository previously then you can update the code with git pull:
- git pull origin master
§sbt
Akka is using the excellent sbt build system. So the first thing you have to do is to download and install sbt. You can read more about how to do that in the sbt setup documentation.
The sbt commands that you'll need to build Akka are all included below. If you want to find out more about sbt and using it for your own projects do read the sbt documentation.
The main Akka sbt build file is project/AkkaBuild.scala, with a build.sbt in each subproject’s directory. It is advisable to allocate at least 2GB of heap size to the JVM that runs sbt, otherwise you may experience some spurious failures when running the tests.
§Building Akka
First make sure that you are in the akka code directory:
- cd akka
§Building
To compile all the Akka core modules use the compile command:
- sbt compile
You can run all tests with the test command:
- sbt test
If compiling and testing are successful then you have everything working for the latest Akka development version.
§Parallel Execution
By default the tests are executed sequentially. They can be executed in parallel to reduce build times, if hardware can handle the increased memory and cpu usage. Add the following system property to sbt launch script to activate parallel execution:
- -Dakka.parallelExecution=true
§Long Running and Time Sensitive Tests
By default are the long running tests (mainly cluster tests) and time sensitive tests (dependent on the performance of the machine it is running on) disabled. You can enable them by adding one of the flags:
- -Dakka.test.tags.include=long-running
- -Dakka.test.tags.include=timing
Or if you need to enable them both:
- -Dakka.test.tags.include=long-running,timing
§Publish to Local Ivy Repository
If you want to deploy the artifacts to your local Ivy repository (for example, to use from an sbt project) use the publish-local command:
- sbt publish-local
§sbt Interactive Mode
Note that in the examples above we are calling sbt compile and sbt test and so on, but sbt also has an interactive mode. If you just run sbt you enter the interactive sbt prompt and can enter the commands directly. This saves starting up a new JVM instance for each command and can be much faster and more convenient.
For example, building Akka as above is more commonly done like this:
- % sbt
- [info] Set current project to default (in build file:/.../akka/project/plugins/)
- [info] Set current project to akka (in build file:/.../akka/)
- > compile
- ...
- > test
- ...
§sbt Batch Mode
It's also possible to combine commands in a single call. For example, testing, and publishing Akka to the local Ivy repository can be done with:
- sbt test publish-local
§Dependencies
You can look at the Ivy dependency resolution information that is created on sbt update and found in ~/.ivy2/cache. For example, the ~/.ivy2/cache/com.typesafe.akka-akka-remote-compile.xml file contains the resolution information for the akka-remote module compile dependencies. If you open this file in a web browser you will get an easy to navigate view of dependencies.
§Scaladoc Dependencies
Akka generates class diagrams for the API documentation using ScalaDoc. This needs the dot command from the Graphviz software package to be installed to avoid errors. You can disable the diagram generation by adding the flag -Dakka.scaladoc.diagrams=false. After installing Graphviz, make sure you add the toolset to the PATH (definitely on Windows).