18 Contributing to Grails

18.1 Report Issues in JIRA

18.2 Build From Source and Run Tests

• JDK (1.6+)
• Git client

Once you have all the pre-requisite packages installed, the next step is to download the Grails source code. The source code is hosted at GitHub in several different git repositories owned by the "grails" GitHub user.

To download the source using git, use the "git clone" command followed by the public URL of the repository you want to clone (download). For example, to clone the "grails-core" repository, run the following:

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

The above will create a "grails-core" directory in your current working directory populated with the project source and the git repository.

Create the required jars

./gradlew libs

This will create everything you need to run Grails. This target also skips running the extensive collection of Grails test classes (Grails' 1000+ tests can bring a single core processor to a grinding halt for some time).

Once the jars have been built, simply set GRAILS_HOME to the checkout directory and add the "bin" directory to your path.

Run 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 tests in src/test/org/codehaus/groovy/grails/orm/hibernate/MappingDslTests.groovy, run the following command:

./gradlew -Dtest.single=MappingDslTest grails-test-suite-persistence:test

You need to give it the specific test suite that the test exists in, just using the "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 actions:

• Add "~/.gradle/cache/com.springsource.springloaded/springloaded-core/jars/springloaded-core-XXXX.jar" to grails-core's classpath.
• Remove "src/test/groovy" from grails-plugin-testing's source path GRECLIPSE-1067
• Add "~/.gradle/cache/javax.servlet.jsp/jsp-api/jars/jsp-api-2.1.jar" 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.

Debug

To debug Grails run the Grails application using:

grails-debug <command>

and then connect to it remotely via the IDE. There should be an option for "remote debugging". Unless you modify the "grails-debug" script, you should connect to port 5005.

If you need to debug stuff that happens during application start-up, 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 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"

18.3 Submit Patches to Grails Core

Forking and Pull Requests

What follows are some guidelines to help ensure that your pull requests are speedily dealt with and provide the information we need. They will also make your life easier!

Create a local branch for your changes

Your life will be greatly simplified if you create a local branch to make your changes on. For example, as soon as you fork a repository and clone the fork locally, execute

git checkout -b mine

This will create a new local branch called "mine" based off the "master" branch. Of course, you can name the branch whatever you like - you don't have to use "mine".

Create JIRAs for non-trivial changes

For any non-trivial changes, raise a JIRA issue if one doesn't already exist. That helps us keep track of what changes go into each new version of Grails.

Include JIRA issue ID in commit messages

This may not seem particularly important, but having a JIRA issue ID in a commit message means that we can find out at a later date why a change was made. Include the ID in any and all commits that relate to that issue. If a commit isn't related to an issue, then there's no need to include an issue ID.

Make sure your fork is up to date

Since the core developers must merge your commits into the main repository, it makes life much easier if your fork on GitHub is up to date before you send a pull request.

Let's say you have the main repository set up as a remote called "upstream" and you want to submit a pull request. Also, all your changes are currently on the local "mine" branch but not on "master". The first step involves pulling any changes from the main repository that have been added since you last fetched and merged:

git checkout master
git pull upstream

This should complete without any problems or conflicts. Next, rebase your local branch against the now up-to-date master:

git checkout mine
git rebase master

What this does is rearrange the commits such that all of your changes come after the most recent one in master. Think adding some cards to the top of a deck rather than shuffling them into the pack.

You'll now be able to do a clean merge from your local branch to master:

git checkout master
git merge mine

Finally, you must push your changes to your remote repository on GitHub, otherwise the core developers won't be able to pick them up:

git push

You're now ready to send the pull request from the GitHub user interface.

Say what your pull request is for

A pull request can contain any number of commits and it may be related to any number of issues. In the pull request message, please specify the IDs of all issues that the request relates to. Also give a brief description of the work you have done, such as: "I refactored the data binder and added support for custom number editors (GRAILS-xxxx)".

18.4 Submit Patches to Grails Documentation

Building the Guide

./gradlew docs

Be warned: this command can take a while to complete and you should probably increase your Gradle memory settings by giving the GRADLE_OPTS environment variable a value like

export GRADLE_OPTS="-Xmx512m -XX:MaxPermSize=384m"

Fortunately, you can reduce the overall build time with a couple of useful options. The first allows you to specify the location of the Grails source to use:

./gradlew -Dgrails.home=/home/user/projects/grails-core docs

The Grails source is required because the guide links to its API documentation and the build needs to ensure it's generated. If you don't specify a grails.home property, then the build will fetch the Grails source - a download of 10s of megabytes. It must then compile the Grails source which can take a while too.

Additionally you can create a local.properties file with this variable set:

grails.home=/home/user/projects/grails-core

grails.home=../grails-core

The other useful option allows you to disable the generation of the API documentation, since you only need to do it once:

./gradlew -Ddisable.groovydocs=true docs

Again, this can save a significant amount of time and memory.

The main English user guide is generated in the build/docs directory, with the guide sub-directory containing the user guide part and the ref folder containing the reference material. To view the user guide, simply open build/docs/index.html.

Publishing

The structure of the user guide is defined in the src/<lang>/guide/toc.yml file, which is a YAML file. This file also defines the (language-specific) section titles. If you add or remove a gdoc file, you must update the TOC as well!

The src/<lang>/ref directory contains the source for the reference sidebar. Each directory is the name of a category, which also appears in the docs. Hence the directories need different names for the different languages. Inside the directories go the gdoc files, whose names match the names of the methods, commands, properties or whatever that the files describe.

Translations

Once you have a copy of the original guide, you can use the {hidden} macro to wrap the English text that you have replaced, rather than remove it. This makes it easier to compare changes to the English guide against your translation. For example:

{hidden}
When you create a Grails application with the [create-app|commandLine] command,
Grails doesn't automatically create an Ant build.xml file but you can generate
one with the [integrate-with|commandLine] command:
{hidden}
Quando crias uma aplicação Grails com o comando [create-app|commandLine], Grails
não cria automaticamente um ficheiro de construção Ant build.xml mas podes gerar
um com o comando [integrate-with|commandLine]:

Because the English text remains in your gdoc files, diff will show differences on the English lines. You can then use the output of diff to see which bits of your translation need updating. On top of that, the {hidden} macro ensures that the text inside it is not displayed in the browser, although you can display it by adding this URL as a bookmark: javascript:toggleHidden(); (requires you to build the user guide with Grails 2.0 M2 or later).

Even better, you can use the left_to_do.groovy script in the root of the project to see what still needs translating. You run it like so:

./left_to_do.groovy es

This will then print out a recursive diff of the given translation against the reference English user guide. Anything in {hidden} blocks that hasn't changed since being translated will not appear in the diff output. In other words, all you will see is content that hasn't been translated yet and content that has changed since it was translated. Note that {code} blocks are ignored, so you don't need to include them inside {hidden} macros.

To provide translations for the headers, such as the user guide title and subtitle, just add language specific entries in the 'resources/doc.properties' file like so:

es.title=El Grails Framework
es.subtitle=...

For each language translation, properties beginning <lang>. will override the standard ones. In the above example, the user guide title will be El Grails Framework for the Spanish translation. Also, translators can be credited by adding a '<lang>.translators' property:

fr.translators=Stéphane Maldini

This should be a comma-separated list of names (or the native language equivalent) and it will be displayed as a "Translated by" header in the user guide itself.

You can build specific translations very easily using the publishGuide_* and publishPdf_* tasks. For example, to build both the French HTML and PDF user guides, simply execute

./gradlew publishPdf_fr

Each translation is generated in its own directory, so for example the French guide will end up in build/docs/fr. You can then view the translated guide by opening build/docs/<lang>/index.html.

All translations are created as part of the Hudson CI build for the grails-doc project, so you can easily see what the current state is without having to build the docs yourself.