(Quick Reference)

20.2 Build From Source and Run Tests - Reference Documentation

Authors: Graeme Rocher, Peter Ledbrook, Marc Palmer, Jeff Brown, Luke Daley, Burt Beckwith, Lari Hotari

Version: 2.3.8

20.2 Build From Source and Run Tests

If you're interested in contributing fixes and features to the core framework, you will have to learn how to get hold of the project's source, build it and test it with your own applications. Before you start, make sure you have:
  • A JDK (1.6 or above)
  • A git client

Once you have all the pre-requisite packages installed, the next step is to download the Grails source code, which is hosted at GitHub in several repositories owned by the "grails" GitHub user. This is a simple case of cloning the repository you're interested in. For example, to getthe core framework run:

git clone http://github.com/grails/grails-core.git

This will create a "grails-core" directory in your current working directory containing all the project source files. The next step is to get a Grails installation from the source.

Creating a Grails installation

If you look at the project structure, you'll see that it doesn't look much like a standard GRAILS_HOME installation. But, it's very simple to turn it into one. Just run this from the root directory of the project:

./gradlew install

This will fetch all the standard dependencies required by Grails and then build a GRAILS_HOME installation. Note that this target skips the extensive collection of Grails test classes, which can take some time to complete.

Once the above command has finished, simply set the GRAILS_HOME environment variable to the checkout directory and add the "bin" directory to your path. When you next type run the grails command, you'll be using the version you just built.

Running the test suite

All you have to do to run the full suite of tests is:

./gradlew test

These will take a while (15-30 mins), so consider running individual tests using the command line. For example, to run the test spec BinaryPluginSpec simply execute the following command:

./gradlew :grails-core:test --tests *.BinaryPluginSpec

Note that you need to specify the sub-project that the test case resides in, because the top-level "test" target won't work....

Developing in IntelliJ IDEA

You need to run the following gradle task:

./gradlew idea

Then open the project file which is generated in IDEA. Simple!

Developing in STS / Eclipse

You need to run the following gradle task:

./gradlew cleanEclipse eclipse

Before importing projects to STS do the following action:

  • Edit grails-scripts/.classpath and remove the line "<classpathentry kind="src" path="../scripts"/>".

Use "Import->General->Existing Projects into Workspace" to import all projects to STS. There will be a few build errors. To fix them do the following:

  • Add the springloaded-core JAR file in $GRAILS_HOME/lib/com.springsource.springloaded/springloaded-core/jars to grails-core's classpath.
  • Remove "src/test/groovy" from grails-plugin-testing's source path GRECLIPSE-1067
  • Add the jsp-api JAR file in $GRAILS_HOME/lib/javax.servlet.jsp/jsp-api/jars to the classpath of grails-web
  • Fix the source path of grails-scripts. Add linked source folder linking to "../scripts". If you get build errors in grails-scripts, do "../gradlew cleanEclipse eclipse" in that directory and edit the .classpath file again (remove the line "<classpathentry kind="src" path="../scripts"/>"). Remove possible empty "scripts" directory under grails-scripts if you are not able to add the linked folder.
  • Do a clean build for the whole workspace.
  • To use Eclipse GIT scm team provider: Select all projects (except "Servers") in the navigation and right click -> Team -> Share project (not "Share projects"). Choose "Git". Then check "Use or create repository in parent folder of project" and click "Finish".
  • Get the recommended code style settings from the mailing list thread (final style not decided yet, currently profile.xml). Import the code style xml file to STS in Window->Preferences->Java->Code Style->Formatter->Import . Grails code uses spaces instead of tabs for indenting.

Debugging Grails or a Grails application

To enable debugging, run:

grails -debug <command>

and then connect to the JVM remotely via the IDE ("remote debugging") using the port 5005. Of course, if you have modified the startGrails script to use a different port number, connect using that one.

In previous versions of Grails there was a grails-debug command. The command is still included in the distribution and is deprecated in favor of the -debug switch to the standard grails command.

If you need to debug stuff that happens during application startup, then you should modify the "grails-debug" script and change the "suspend" option from 'n' to 'y'. You can read more about the JPDA connection settings TODO here: http://java.sun.com/j2se/1.5.0/docs/guide/jpda/conninv.html#Invocation.

It's also possible to get Eclipse to wait for incoming debugger connections and instead of using "-Xrunjdwp:transport=dt_socket,server=y,suspend=n,address=5005" you could use this "-Xrunjdwp:transport=dt_socket,server=n,address=8000" (which assumes the Eclipse default port for remote java applications) Inside eclipse you create a new "Remote Java Application" launch configuration and change the connection type to "Standard (Socket Listen)" and click debug. This allows you to start a debugger session in eclipse and just leave it running and you're free to debug anything without having to keep remembering to relaunch a "Socket Attach" launch configuration. You might find it handy to have 2 scripts, one called "grails-debug", and another called "grails-debug-attach"