Developing Drools and jBPM

If you want to build or contribute to a droolsjbpm project, read this document.

This document will save you and us a lot of time by setting up your development environment correctly. It solves all known pitfalls that can disrupt your development. It also describes all guidelines, tips and tricks. If you want your pull requests (or patches) to be merged into master, please respect those guidelines.

If you are reading this document with a normal text editor, please take a look at the more readable formatted version.

If you discover pitfalls, tips and tricks not described in this document, please update it using the markdown syntax.

Table of content

• Source control with Git

• Building with Maven

• Developing with Eclipse

• Developing with IntelliJ

• Team communication

• Writing documentation

• Releasing

• FAQ

Quick start

If you don't want to contribute to this project and you know git and maven, these build instructions should suffice:

• To build 1 repository, for example guvnor:

    $ git clone git@github.com:droolsjbpm/guvnor.git
    $ cd guvnor
    $ mvn clean install -DskipTests
  

• To build all repositories:

    $ git clone git@github.com:droolsjbpm/droolsjbpm-build-bootstrap.git
    $ droolsjbpm-build-bootstrap/script/git-clone-others.sh
    $ droolsjbpm-build-bootstrap/script/mvn-all.sh clean install -DskipTests
  

If you want to contribute to this project, read the rest this file!

Source control with Git

Installing and configuring git

• Install it in your OS:

  • Linux: Install the package git

      $ sudo apt-get install git
    

    Tip: Also install gitk to visualize your git log:

      $ sudo apt-get install gitk
    

  • Windows, Mac OSX: Download from the git website.

    Tip for Mac OSX: Also install gitx to visualize your git log.

  • More info in github's git installation instructions.

• Check if git is installed correctly.

    $ git --version
    git version 1.7.1
  

• Configure git correctly:

    $ git config --global user.name "My Full Name"
    $ git config --global user.email myAccount@gmail.com
    $ git config --global -l
    user.name=Geoffrey De Smet
    user.email=gds...@gmail.com
  

  • Warning: the field user.name is your full name, not your username.

  • Note: the field user.email should match an email address of your github account.

  • More info on github.

• Get a github account

  • And add your public key on github: Follow these instructions.

• To learn more about git, read the free book Git Pro.

Getting the sources locally

Because you 'll probably want to change our code, it's recommended to fork our code before cloning it, so it's easier to share your changes with us later. For more info on forking, read Github's help on forking.

• First fork the repository you want to work on, for example guvnor:

  • Surf to the blessed repositories on github and log in.

    • Note: Every git repository can be build alone. You only need to fork/clone the repositories you're interested in (guvnor in this case).

  • Surf to the specific repository (guvnor)

  • Click the top right button Fork

  • Note: by forking the repository, you can commit and push your changes without our consent and we can easily review and then merge your changes into the blessed repository.

• Clone your fork locally:

    # First make a directory to hold all the droolsjbpm projects
    $ mkdir droolsjbpm
    $ cd droolsjbpm
  
    # Then clone the repository you want to clone.
    $ git clone git@github.com:MY_GITHUB_USERNAME/guvnor.git
    $ cd guvnor
    $ ls
  

  • Warning: Always clone with the SSH URL, never clone with the HTTPS URL because the latter is unreliable.

  • Note: it's highly recommended to name the cloned directory the same as the repository (which is the default), so the helper scripts work.

  • By default you will be looking at the sources of the master branch, which can be very unstable.

    • Use git checkout to switch to a more stable branch or tag:

        $ git checkout 5.2.0.Final
      

• Add the blessed repository as upstream (if you've directly cloned the blessed repository, don't do this):

    $ git remote add upstream git@github.com:droolsjbpm/guvnor.git
    $ git fetch upstream
  

Working with git

• First make a topic branch:

    $ git checkout master
    $ git checkout -b myFirstTopic
  

  • Don't litter your local master branch: keep it equal to remotes/upstream/master

  • 1 branch can have only 1 pull request, because the pull requests evolves as you add more commits on that branch.

• Make changes, run, test and document them, then commit them:

    $ git commit -m"Fix typo in documentation"
  

• Push those commits on your topic branch to your fork

    $ git push myFirstTopic
  

• Get the latest changes from the blessed repository

  • Set your master equal to the blessed master:

      $ git fetch upstream
      $ git checkout master
      # Warning: this deletes all changes/commits on your local master branch, but you shouldn't have any!
      $ git reset --hard upstream/master
    

  • Start a new topic branch and set the code the same as the blessed master:

    $ git fetch upstream && git checkout -b mySecondTopic && git reset --hard upstream/master

  • If you have a long-running topic branch, merge master into it:

      $ git fetch upstream
      $ git merge upstream/master
    

    • If there are merge conflicts:

        $ git mergetool
        $ git commit
      

      or

        $ git status
        $ gedit conflicted-file.txt
        $ git add conflicted-file.txt
        $ git commit
      

      Many people get confused when a merge conflict occurs, because you're in limbo. Just fix the merge conflicts and commit (even if the git seems to contain many files), only then is the merge over. Then run git log to see what happened. The many files in the merge conflict resolving commit are a side-affect of non-linear history.

• Tips and tricks

  • To see the details of your local, unpushed commits:

      $ git diff origin...HEAD
    

  • To run a git command (except clone) over all repositories (only works if you cloned all repositories):

      $ cd ~/projects/droolsjbpm
      $ droolsjbpm-build-bootstrap/script/git-all.sh push
    

    • Note: the git-all.sh script is working directory independent.

    • Linux tip: Create a symbolic link to the git-all.sh script and place it in your PATH by linking it in ~/bin:

        $ ln -s ~/projects/droolsjbpm/droolsjbpm-build-bootstrap/script/git-all.sh ~/bin/droolsjbpm-git
      

      For command line completion, add the following line in ~/.bashrc:

        $ complete -o bashdefault -o default -o nospace -F _git droolsjbpm-git
      

Share your changes with a pull request

A pull request is like a patch file, but easier to apply, more powerful and you'll be credited as the author.

• Creating a pull request

  • Push all your commits to a topic branch on your fork on github (if you haven't already).

    • You can only have 1 pull request per branch, so it's advisable to use topic branches to avoid mixing your changes.

  • Surf to that topic branch on your fork on github.

  • Click the button Pull Request on the top of the page.

• Accepting a pull request

  • Surf to the pull request page on github.

  • Review the changes

  • Click the button Merge help on the bottom of the page and follow the instructions of github to apply those changes on the blessed master.

    • Or use the button Merge if there are no merge conflicts.

Building with Maven

All projects use Maven 3 to build all their modules.

Installing Maven

• Get Maven

  • Download Maven and follow the installation instructions.

• Linux

  • Note: the apt-get version of maven is probably not up-to-date enough.

  • Linux trick to easily upgrade to future versions later:

    • Unzip maven to ~/opt/build

    • Create a version-independent link:

        $ cd ~/opt/build/
        $ ln -s apache-maven-3.0.3 apache-maven
      

      Next time you only have to remove the link and recreate the link to the new version.

    • Add this to your ~/.bashrc file:

        export M3_HOME="~/opt/build/apache-maven"
        export PATH="$M3_HOME/bin:$PATH"
      

  • Give more memory to maven, so it can the big projects too:

    • Add this to your ~/.bashrc file:

      export MAVEN_OPTS="-Xms256m -Xmx1024m -XX:MaxPermSize=512m"

• Windows:

  • Give more memory to maven, so it can the big projects too:

    • Open menu Configuration screen, menu item System, tab Advanced, button environment variables:

      set MAVEN_OPTS="-Xms256m -Xmx1024m -XX:MaxPermSize=512m"

• Check if maven is installed correctly.

    $ mvn --version
    Apache Maven 3.0.3 (...)
    Java version: 1.6.0_24
  

  Note: the enforcer plugin enforces a minimum maven and java version.

Running the build

• Go into a project's base directory, for example guvnor:

    $ cd ~/projects/droolsjbpm
    $ ls
    drools  droolsjbpm-build-bootstrap  droolsjbpm-build-distribution  droolsjbpm-integration  droolsjbpm-knowledge  droolsjbpm-tools  drools-planner  guvnor
    $ cd guvnor
    $ ls
    ...  guvnor-repository  guvnor-webapp  pom.xml
  

  Notice you see a pom.xml file there. Those pom.xml files are the heart of Maven.

• Run the build:

    $ mvn clean install -DskipTests
  

  The first build will take a long time, because a lot of dependencies will be downloaded (and cached locally).

  It might even fail, if certain servers are offline or experience hiccups. In that case, you 'll see an IO error, so just run the build again.

  After the first successful build, any next build should be fast and stable.

• Try running a different profile by using the option -D<profileActivationProperty>:

    $ mvn clean install -DskipTests -Dfull
  

  There are 3 profile activation properties:

  • none: Fast, for during development

  • full: Slow, but builds everything (including documentation). Used by hudson and during releases.

  • soa: prunes away the non-enterprise stuff

• To run a maven build over all repositories (only works if you cloned all repositories):

    $ cd ~/projects/droolsjbpm
    $ droolsjbpm-build-bootstrap/script/mvn-all.sh -DskipTests clean install
  

  • Note: the mvn-all.sh script is working directory independent.

• Warning: The first mvn build of a day will download the latest SNAPSHOT dependencies of other droolsjbpm projects, unless you build all those droolsjbpm projects from source. Those SNAPSHOTS were build and deployed last night by hudson jobs.

  • If you 've pulled all changes (or cloned a repository) today, this is a good thing: it saves you from having to download and build all those other latest droolsjbpm projects from source.

  • If you haven't pulled all changes today, this is probably a bad thing: you 're probably not ready to deal with those new snapshots.

    In that case, add -nsu (= --no-snapshot-updates) to the mvn command to avoid downloading those snapshots:

      $ mvn clean install -DskipTests -nsu
    

    Note that using -nsu will also make the build faster.

Running tests

Guvnor uses Arquillian to run tests in a J2EE container and hence tests need to be ran differently to others.

• Guvnor

    $ cd ~/projects/droolsjbpm/guvnor/guvnor-webapp-drools
    $ mvn integration-test [-Dtest=ATestClassName]
  

• All other modules

    $ cd ~/projects/droolsjbpm/drools
    $ mvn test [-Dtest=ATestClassName]
  

Configuring Maven

To deploy snapshots and releases to nexus, you need to add this to the file ~/.m2/settings.xml:

 <settings>
   ...
   <servers>
     <server>
       <id>jboss-snapshots-repository</id>
       <username>jboss.org_username</username>
       <password>jboss.org_password</password>
     </server>
     <server>
       <id>jboss-releases-repository</id>
       <username>jboss.org_username</username>
       <password>jboss.org_password</password>
     </server>
   </servers>
   ...
 </settings>

Furthermore, you'll need nexus rights to be able to do this.

More info in the JBoss.org guide to get started with Maven.

Developing with Eclipse

Before running Eclipse

• Do not use an Eclipse version older than 3.6 (helios).

• Avoid an OutOfMemoryException and a StackOverflowError when building.

  Open $ECLIPSE_HOME/eclipse.ini and add/change this: on openFile -vmargs:

    openFile
    -vmargs
    ...
    -XX:MaxPermSize=512m
    -Xms512m
    -Xmx1024m
    -Xss1024k
  

• Only on Mac, also add these lines to avoid a Mac-specific p2 bug with tycho 0.11.0 in droolsjbpm-tools:

    -startup
    ../../../plugins/org.eclipse.equinox.launcher_1.1.0.v20100507.jar
    --launcher.library
    ../../../plugins/org.eclipse.equinox.launcher.cocoa.macosx.x86_64_1.1.1.R36x_v20100810
  

  TODO: Remove this note when we upgrade to tycho 0.12.0 (if that uses a p2 director that fixes it)

Configuring the project with the m2eclipse plugin

The m2eclipse plugin is a plugin in Eclipse for Maven. This is the new way (and compatible with tycho).

• Open Eclipse

• Follow the installation instructions of m2eclipse.

  • Follow the link Installing m2eclipse at the bottom.

• Click menu File, menu item Import, tree item Maven, tree item Existing Maven Projects.

• Click button Browse, select a repository directory. For example ~/projects/droolsjbpm/guvnor.

• Unfold Advanced, textfield Profiles: notSoaProfile,fullProfile.

For more information, see the m2eclipse book

Configuring the project with the deprecated maven-eclipse-plugin

The maven-eclipse-plugin plugin is a plugin in Maven for Eclipse. This is the old way (of which the development has stopped).

Run this command to generate .project and .classpath files:

$ mvn eclipse:eclipse

• Open Eclipse

• Menu item Import existing projects, navigate to the project base directory, select all the projects (= modules) it lists.

Important note: mvn eclipse:eclipse does not work for our eclipse plugins because it is not compatible with tycho (and never will be).

Configuring Eclipse

• Force language level 5 (not 6), to fail-fast on implemented interface methods that are annotated with @Override.

  • Open menu Window, menu item Preferences

  • Click tree item Java, tree item Compiler, section JDK Compliance, combobox Compiler compliance level should be 1.5.

• Remove the test resources Java Build Path exclusion filter to ensure JUnit tests ran inside Eclipse can find the necessary resources.

  • Right-click the project

  • Select menu item Build Path, sub-menu item Configure build path...

  • On the Sources tab, scroll down to <project>\src\test\resources and expand tree

  • Select Excluded and click Remove. The filter should show as (none)

• Set the correct file encoding (UTF-8 except for properties files) and end-of-line characters (unix):

  • Open menu Window, menu item Preferences.

  • Click tree item General, tree item Workspace

    • Label Text file encoding, radiobutton Other, combobox UTF-8.

    • Label New text file delimiter, radiobutton Other, combobox Unix.

  • Click tree item XML, tree item XML Files.

    • Combobox Encoding: ISO 10646/Unicode(UTF-8).

  • Click tree item CSS, tree item CSS Files.

    • Combobox Encoding: ISO 10646/Unicode(UTF-8).

  • Open tree item HTML, tree item HTML Files.

    • Combobox Encoding: ISO 10646/Unicode(UTF-8).

  • Note: normal i18n properties files must be in ISO-8859-1 as specified by the java ResourceBundle contract.

    • Note on note: GWT i18n properties files override that and must be in UTF-8 as specified by the GWT contract.

• Set the correct number of spaces when pressing tab:

  • Warning: If you imported the eclipse-formatter.xml file, you don't need to set it for Java, but you do need to set it for XML anyway!

  • Open menu Window, menu item Preferences.

    • If you have project specific settings enabled instead, right click on the project and click the menu item Properties.

  • Click tree item Java, tree item Code Style, tree item Formatter.

    • Click button Edit of the active profile, tab Indentation

    • Combobox Tab policy: spaces only

    • Textfield Indentation size: 4

    • Textfield Tab size: 4

    • Note: If it is a build-in profile, you 'll need to change its name with the textfield on top.

  • Click tree item XML, tree item XML Files, tree item Editor.

    • Radiobutton Indent using space: on

    • Textfield Indentation size: 2

  • Click tree item General, tree item Editors, tree item Text Editors.

    • Checkbox Insert spaces for tabs: on

    • Textfield Displayed tab width: 4

  • Click tree item CSS Files, tree item Editor.

    • Radiobutton Indent using space: on

    • Textfield Indentation size: 4

• Set the correct file headers (do not include @author or a meaningless javadoc):

  • Open menu Window, menu item Preferences.

  • Click tree item Java, tree item Code Style, tree item Code Templates.

  • Click tree Configure generated code and comments, tree item Comments, tree item types.

  • Remove the line @author Your Name.

    • We do not accept @author lines in source files, see FAQ below.

  • Remove the entire javadoc as automatically templated data is meaningless.

• Set the correct license header

  Eclipse JEE Helios currently has no build-in support of license headers, but you can configure it for new files.

  • Open menu Window, menu item Preferences.

    • If you have project specific settings enabled instead, right click on the project and click the menu item Properties.

  • Click tree item Java, tree item Code Style, tree item Copy templates.

  • Click tree item Comments, tree item Files.

  • Replace the text area with the java multi-line comment version of droolsjbpm-build-bootstrap/ide-configuration/LICENSE-ASL-2.0-HEADER.txt:

    /*

    • Copyright 2011 JBoss Inc
    • Licensed under the Apache License, Version 2.0 (the "License");
    • you may not use this file except in compliance with the License.
    • You may obtain a copy of the License at

    •   http://www.apache.org/licenses/LICENSE-2.0
      

    • Unless required by applicable law or agreed to in writing, software
    • distributed under the License is distributed on an "AS IS" BASIS,
    • WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    • See the License for the specific language governing permissions and
    • limitations under the License. */

  • Note: Do not start or end with a newline character

  • Note: Do not start with /**: it is not a valid javadoc.

  • Update the year (2011) every year.

Extra Eclipse plugins

• Enable git support

  • Open menu Help, menu item Install new software.

  • Click combobox Update site Helios, tree item Collaboration, tree item Eclipse EGit.

• GWT plugin

  • Download and install the Eclipse GWT plugin

    • Note: it is recommended to keep your Eclipse GWT plugin version in sync with the GWT version that we use.

  • In Package Explorer, right click on the project guvnor-webapp, menu item Properties.

    • Enable the GWT aspect:

      • Click tree item Google, tree item Web Toolkit Settings...

      • Checkbox Use google Web Tookit: on

      • List Entry Point Modules should contain Guvnor - org.drools.guvnor (and optionally FastCompiledGuvnor too).

    • The gwt-dev jar needs to be first on the compilation classpath (the java.lang.NoSuchFieldError: warningThreshold problem)

      • Click tree item Java Build Path

      • Tab Libraries, button Add Library..., list item Google Web Toolkit, button Next, button Finish

      • Tab Order and Export, select GWT SDK ..., button Top

  • Verify that you have a web browser configured in Eclipse:

    • Open menu Window, menu item Preferences.

    • Click tree General, tree item Web Browser, radiobutton Use external web browser.

    • Click button New..., textfield Name firefox, textfield Location /usr/bin/firefox, textfield Parameters %URL%, button OK.

    • Check the checkbox next to firefox.

  • Run GWT in hosted mode

    • Open project context menu Properties, Google->Web application->

       * This project has a WAR directory, tick
      
       * WAR directory, `target/guvnor-webapp-5.4.0-SNAPSHOT` (this will differ for different releases)
      
       * You will need to have completed a maven install, as explained above to generate the `target/guvnor-webapp-5.4.0-SNAPSHOT` directory
      
       * Launch and deploy from this directory, tick
      

    • Open menu Run, menu item Run configurations...

    • In the list, select Web Application, button new launch configuration

    • Tab Main, Project: guvnor-webapp

    • Tab Main, Ensure Main class is: com.google.gwt.dev.DevMode

    • Tab GWT, list Available Modules: Guvnor - org.drools.guvnor

    • Tab Arguments, Ensure Program Arguments are : -war <path-to-war-folder> -remoteUI "${gwt_remote_ui_server_port}:${unique_id}" -startupUrl index.jsp -logLevel INFO -codeServerPort 9997 -port 8888 org.drools.guvnor.FastCompiledGuvnor org.drools.guvnor.Guvnor.

       * For example: `-war /home/manstis/workspaces/git/droolsjbpm/guvnor/guvnor-webapp/target/guvnor-webapp-5.4.0-SNAPSHOT -remoteUI "${gwt_remote_ui_server_port}:${unique_id}" -startupUrl index.jsp -logLevel INFO -codeServerPort 9997 -port 8888 org.drools.guvnor.FastCompiledGuvnor org.drools.guvnor.Guvnor`
      

    • Button Run.

  • In your workspace, in the tab Development Mode, double click on the Guvnor URL.

  • If you encounter a java.lang.NoSuchFieldError: warningThreshold error you need to follow the steps here, i.e.

    • Add GWT-SDK to your classpath (even though it is a Maven dependency)

    • On your Java Build Path, Order and Export tab, move GWT-SDK to the top

Eclipse plugin development

• Installing a droolsjbpm eclipse plugin into a fresh Eclipse from a local update site.

  • Follow the intructions in the description entity in the org.drools.updatesite pom.xml file.

Developing with IntelliJ

Before running IntelliJ

• Avoid an OutOfMemoryException while editing or building.

  Open $IDEA_HOME/bin/idea.vmoptions and change the first 3 values to this:

    -Xms512m
    -Xmx1024m
    -XX:MaxPermSize=512m
  

Configuring the project with the maven integration

IntelliJ has very good build-in support for Maven.

• Open IntelliJ.

• Click menu File, menu item New project.

  • Click radiobutton Create project from scratch, button Next

  • Textfield name: droolsjbpm

  • Textfield Project files location: ~/projects/droolsjbpm

  • Checkbox Create module: off

• Click menu File, menu item New module

  • Radiobutton Import from external model, button Next, button Next

  • Textfield Root directory: ~/projects/droolsjbpm/guvnor

    • That is the directory that contains the multiproject pom.xml file from a project base directory.

  • Button Next, check in the Selected profiles notSoaProfile and fullProfile, button Next, button Finish.

  • Go grab a coffee while it's indexing.

  • Repeat if you want to work on more than 1 droolsjbpm project.

Note: Don't use the maven-idea-plugin on the command line with mvn: it's dead.

Configuring IntelliJ

• Force language level 5 (not 6), to fail-fast on implemented interface methods that are annotated with @Override.

  • Open menu File, menu item Project Structure

  • Click list item Modules, for each module, tab Sources, combobox Language level should be automatically set to 5.0 ...

• Avoid that changes in some resources are ignored in the next run/debug (and you are forced to use mvn)

  • Open menu File, menu item Settings

  • Click tree item Compiler, textfield Resource patterns: change to !?*.java (remove other content)

• Avoid a StackOverflowError when building

  • Open menu File, menu item Settings

  • Click tree item Compiler, tree item Java Compiler, textfield Additional command line parameters

  • Add -J-Xss1024k so it becomes something like -target 1.5 -J-Xss1024k

• Include files with non-default extensions in your searches and refactors

  • Open menu File, menu item Settings

  • Click tree item File Types, in the list Recognized File Types:

    • Next to list Recognized File Types, click on the button Add...

      • Textfield name: DRL files

      • Textfield Line comment: //

      • Textfield Block comment start: /*

      • Textfield Block comment end: */

      • Check the checkboxes Support paired braces, Support paired brackets and Support parens

      • Add some keywords: rule, when, then, end, ...

      • Click button ok

    • Next to the list Registered Patterns, use the button Add...:

      • For DRL files, add *.drl, *.mvel, *.drt, *.dslr

      • For Text files, add *.md

      • For Properties files, add *.dsl

      • For XML Files, add *.rf

• Optionally import one of our code styles:

  • If you don't do this, you need to set the file encoding and number of spaces correctly manually.

  • Choose the correct one from droolsjbpm-build-bootstrap/ide-configuration

    • The droolsjbpm-knowledge and drools repositories use original, not java-conventions.

  • Copy to ~/.IntelliJIdea10/config/codestyles/ (on mac: ~/Library/Preferences/IntelliJIdea10/config/codestyles/)

  • Restart, open menu File, menu item Settings

  • Click tree item Code Style and select it.

• Set the correct file encoding (UTF-8 except for properties files) and end-of-line characters (unix):

  • Open menu File, menu item Settings

  • Click tree item Code Style, tree item General

    • Combobox Line separator (for new files): Unix

  • Click tree item File Encodings

    • Combobox IDE Encoding: UTF-8

    • Combobox Default encoding for properties files: ISO-8859-1

      • Note: normal i18n properties files must be in ISO-8859-1 as specified by the java ResourceBundle contract.

        • Note on note: GWT i18n properties files override that and must be in UTF-8 as specified by the GWT contract.

• Set the correct number of spaces when pressing tab:

  • Open menu File, menu item Settings

  • Click tree item Code Style, tree item General

  • Click tab Java

    • Checkbox Use tab character: off

    • Textfield Tab size: 4

    • Textfield Indent: 4

    • Textfield Continuation indent: 8

  • Open tab XML

    • Checkbox Use tab character: off

    • Textfield Tab size: 2

    • Textfield Indent: 2

    • Textfield Continuation indent: 4

• Set the correct file headers (do not include @author or a meaningless javadoc):

  • Open menu File, menu item Settings

  • Click tree item File templates, tab Includes, list item File Header

  • Remove the line @author Your Name.

    • We do not accept @author lines in source files, see FAQ below.

  • Remove the entire javadoc as automatically templated data is meaningless.

• Set the correct license header

  • Open menu File, menu item Settings

  • Click tree item Copyright, tree item Copyright profiles

    • Click button + to add a Copyright profile

    • Textfield name: JBoss Inc

    • Textarea with content:

        Copyright $today.year JBoss Inc
      
        Licensed under the Apache License, Version 2.0 (the "License");
        you may not use this file except in compliance with the License.
        You may obtain a copy of the License at
      
              http://www.apache.org/licenses/LICENSE-2.0
      
        Unless required by applicable law or agreed to in writing, software
        distributed under the License is distributed on an "AS IS" BASIS,
        WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
        See the License for the specific language governing permissions and
        limitations under the License.
      

    • Note: Do not start or end with a newline character

    • Note: Do not start with /**: it is not a valid javadoc.

  • Click tree item Copyright

    • Combobox Default project copyright: JBoss Inc

Extra IntelliJ plugins

• Enable git support

  • Open menu File, menu item Other Settings, menu item Configure plugins.

  • Check Git.

• GWT plugin

  • Open menu File, menu item Project structure

    • For the module guvnor-webapp, add the new aspect GWT if you haven't already.

      • Textfield Compiler maximum heap size (Mb): 512

  • Open menu Run, menu item Edit configurations

    • Add new GWT configuration

      • Combobox module guvnor-webapp.

    • Run that configuration.

• Tomcat exploded war deployment

  • Open menu File, menu item Project structure

    • Select tree item Artifacts, list item guvnor-webapp:war exploded

      • Checkbox Build on make: on

  • Open menu Run, menu item Edit configurations

    • Add new Tomcat server, local

      • Tab deployment, add Artifact guvnor-webapp:war exploded.

      • Panel Before launch, checkbox Build 'guvnor-webapp:war exploded' artifact: on

    • Run that configuration.

Team communication

To develop a great project as a team, we need to communicate efficiently as a team.

Team workflows

• Fixing a community issue in JIRA:

  • Find/create the issue in JIRA (Drools, [jBPM](https://issues.jboss.org/browse/JBPM], Guvnor

  • Fix the issue and push those changes to the appropriate branch(es) on github.

  • Change the Status to Resolved.

    • Once the reporter verifies the fix, he changes Status to Closed. Or we bulk change it to Closed after a year.

• (Red Hat developers only) Fixing BRMS issues in Bugzilla:

  • Find an issue in Bugzilla. Change Status to ASSIGNED and Assigned To to yourself.

  • Fix the issue and push those changes to the appropriate branch(es) on github.

    • This will likely require back porting or forward porting, because the issue must be fixed on master too.

  • Change the Status to MODIFIED.

    • Once the new product version is build, they change Status to ON_QA.

    • Once QA verifies the fix, they change Status to Verified.

Knowing what's going on

• Subscribe to the dev list and check it daily.

  • Send a summary of every important organizational or structural decision to the dev list.

  • If you (accidentally) push a change that can severely hinder or disrupt other developers (such as a compilation failure), notify the dev list.

• Subscribe to the RSS feeds.

  • It's recommend to subscribe at least to the RSS feeds of the project/repositories you're working on.

  • Prefer an RSS reader which shows which RSS articles you've already read, such as:

    • Thunderbird

      • Open menu File, menu item Subscribe.

      • Tip: create a new, separate directory for each feed: some feeds (such as about the project you are working on) are more important to you than others.

    • Google Reader

  • Subscribe to jira issue changes:

    • JBRULES

    • JBPM

    • GUVNOR

  • Subscribe to github repository commits:

    • droolsjbpm-build-bootstrap

    • droolsjbpm-knowledge

    • drools

    • drools-planner

    • jbpm

    • droolsjbpm-integration

    • guvnor

    • droolsjbpm-tools

    • droolsjbpm-build-bootstrap

  • Subscribe to hudson

    • with the Firefox plugin to easily see in your status bar which builds are failing (recommended):

      • After installation, right click on the hudson icon in the lower right corner.

      • Click menu item Preferences, tab Feed, textfield poll interval 30 minutes.

      • Click menu item Preferences, tab Display, combox Display latest build on status bar.

      • Go to the hudson job of the projects you're working on:

        • guvnor

      • Right click in the lower left corner on the All feed link, menu item Add link to jenkins build monitor.

    • Otherwise, check the hudson website often.

      • Note: the public hudson is a mirror of the VPN internal Red Hat hudson and is sometimes stale.

        • If you think this can be the case, check the build times.

• Join us on IRC: irc.codehaus.org #drools #jbpm #guvnor

Writing documentation

• Optionally install a DocBook editor to write documentation more comfortably, such as:

  • XMLmind Personal Edition

    • Open menu Options, menu item Preferences....

    • Click tree item Save

      • Combobox Encoding: UTF-8

      • Textfield Identation: 2

      • Textfield Max. line length: 120

      • Checkbox Before saving, make a backup copy of the file: off

        • To avoid committing backups to source control.

        • Source control history is better than backups.

• To generate the html and pdf output run maven with -Dfull:

    $ cd droolsjbpm
    $ cd guvnor/guvnor-docs
    $ mvn clean install -Dfull
    ...
    $ firefox target/docbook/publish/en-US/html_single/index.html
  

• Read and follow the documentation guidelines.

• The Drools Expert manual uses railroad diagrams.

  These are generated from a BNF file into images files with the application Ebnf2ps, Automatic Railroad Diagram Drawing

Releasing

Expecting a release

• Use a non-SNAPSHOT version for all dependencies. Get those dependencies (for example mvel) released if needed.

  • The MVEL release usually becomes a blocker for the Drools release, try to get MVEL released one week before the Drools release. This way you have time to test with the real thing.

• Run findbugs on all projects:

    $ mvn site -DskipTests
    $ firefox */target/site/findbugs.html
  

• Releasing Drools with or without jBPM?

  • If jBPM must not be released, then do this in any shell before running the first release command:

      $ export withoutJbpm=true
    

  • Furthermore, verify that the droolsjbpm-parent pom's properties are not using a SNAPSHOT version of jBPM.

Creating a release branch

A release branch name should always end with .x so it looks different from a tag name and a topic branch name.

• Simply use the script script/release/create-release-branches.sh with the drools and jbpm release branch name:

    $ droolsjbpm-build-bootstrap/script/release/create-release-branches.sh 5.2.x 5.1.x
  

• Switch back and forth from master to the release branches for all git repositories

  • If you haven't made the branches yourself, first make sure your local repository knows about them:

      $ droolsjbpm-build-bootstrap/script/git-all.sh fetch
    

  • Switch to master with script/git-checkout-all.sh

      $ droolsjbpm-build-bootstrap/script/git-checkout-all.sh master master
    

  • Update master to the next SNAPSHOT version to avoid clashing the artifacts on nexus of master and the release branch:

      $ droolsjbpm-build-bootstrap/script/release/update-version-all.sh 5.2.0-SNAPSHOT 5.2.0.SNAPSHOT 5.3.0-SNAPSHOT 5.3.0.SNAPSHOT 5.1.0-SNAPSHOT 5.1.0.SNAPSHOT 5.2.0-SNAPSHOT 5.2.0.SNAPSHOT
    

  • Switch back to the release branch name with script/git-checkout-all.sh with drools and jbpm release branch name:

      $ droolsjbpm-build-bootstrap/script/git-checkout-all.sh 5.2.x 5.1.x
    

  • Do a sanity check with grep -lir "5.2.x" * | grep -v "target". This lists all the files that are still using the old version, if there are any.

Releasing from a release branch

• To produce the distribution zips, build with -Dfull:

    $ droolsjbpm-build-bootstrap/script/mvn-all.sh -Dfull clean install
  

  • Warning: Use JDK 1.6, because in JDK 1.5 the module guvnor-repository-connector-modeshape is not build.

  • Warning: Verify that workspace contains no uncommitted changes or rogue module directories of older branches:

      $ droolsjbpm-build-bootstrap/script/git-all.sh status
    

    • Otherwise the sources in a distribution zip might contain archived module directories with old binaries.

• Do a sanity check of the artifacts by running each runExamples.sh from the zips.

  • The distribution zips are in the directory droolsjbpm-build-distribution/droolsjbpm-uber-distribution/target.

If everything is perfect (compiles, hudson is all blue and sanity checks succeed):

• Define the version and adjust the sources accordingly:

  • First define the version.

    • There are only 4 acceptable patterns:

      • major.minor.micro.Alpha[n], for example 1.2.3.Alpha1

      • major.minor.micro.Beta[n], for example 1.2.3.Beta1

      • major.minor.micro.CR[n], for example 1.2.3.CR1

      • major.minor.micro.Final, for example 1.2.3.Final

    • The OSGi version is exactly the same as the pom version.

    • See the JBoss version conventions

      • Not following those, for example 1.2.3 or 1.2.3.M1 results in OSGi eclipse updatesite corruption.

    • The version has 3 numbers and qualifier. The qualifier is case-sensitive and starts with a capital.

      • Use the exact same version everywhere (especially in URL's).

  • Adjust the version in the poms, manifests and other eclipse stuff.

      $ droolsjbpm-build-bootstrap/script/release/update-version-all.sh 5.2.0-SNAPSHOT 5.2.0.SNAPSHOT 5.2.0.Final 5.2.0.Final 5.1.0-SNAPSHOT 5.1.0.SNAPSHOT 5.1.0.Final 5.1.0.Final
    

    • Note: the arguments are droolsOldVersion droolsOldOsgiVersion droolsNewVersion droolsNewOsgiVersion jbpmOldVersion jbpmOldOsgiVersion jbpmNewVersion jbpmNewOsgiVersion.

    • WARNING: FIXME the update-version-all script does not work correctly if you are releasing a hotfix version.

    • Commit those changes (so you can tag them properly):

        $ droolsjbpm-build-bootstrap/script/git-all.sh commit -m"Set release version: 5.2.0.Final"
      

  • Update the Compatibility matrix in droolsjbpm-knowledge/droolsjbpm-introduction-docs/src/main/docbook/en-US/Chapter-Compatibility/Chapter-Compatibility_matrix.xml.

    • Cherry pick that change to master too.

• Create the tag locally. The arguments are the Drools version, the jBPM version:

    $ droolsjbpm-build-bootstrap/script/release/git-tag-locally-all.sh 5.2.0.Final 5.1.0.Final
  

• Deploy the artifacts:

    $ droolsjbpm-build-bootstrap/script/mvn-all.sh -Dfull -DskipTests clean deploy
  

  • The release skips the tests because jbpm and guvnor have random failing tests

• Go to nexus, menu item Staging repositories, find your staging repository.

  • Look at the files in the repository

  • Button close

    • This will validate the nexus rules. If any fail: fix the issues, and force retag locally.

• Do another sanity check of the artifacts by running the examples from the zips.

  • Go to droolsjbpm-build-distribution/droolsjbpm-uber-distribution/target and check the zips

    • Start the examples.sh script for drools, droolsjbpm-integration and drools-planner

    • Deploy the guvnor jboss-as-7.0 war to guvnor and surf to it:

      • Install the mortgages examples, build it and run the test scenario's

    • Warning: the manual dir in some zips have been known to have zip problems: they look fine zipped, but are empty unzipped.

      • This regularly occurs on ge0ffrey's machine for droolsjbpm-integration and drools-planner on the directories manual and javadocs.

      • Solution: unzip them, grab the good content from the relevant *-distribution module and rezip it (yes nexus zip's are wrong).

• This is the point of no return.

  • Warning: The slightest change after this requires the use of the next version number!

    • NEVER TAG OR DEPLOY A VERSION THAT ALREADY EXISTS AS A PUSHED TAG OR A DEPLOY!!!

      • Except deploying SNAPSHOT versions.

      • Git tags are cached on developer machines forever and are never refreshed.

      • Maven non-snapshot versions are cached on developer machines and proxies forever and are never refreshed.

    • So even if the release is broken, do not reuse the same version number! Create a hotfix version.

• Define the next development version an adjust the sources accordingly:

  • Define the next development version on the branch from which you are releasing.

    • There are only 1 acceptable pattern:

      • major.minor.micro-SNAPSHOT, for example 1.2.0-SNAPSHOT or 1.2.1-SNAPSHOT

    • Warning: This release branch should never have the same SNAPSHOT version as master or another branch.

      • If you're releasing a Final, increment the micro number, not the minor number.

    • The OSGi version ends in .SNAPSHOT instead of -SNAPSHOT.

  • Adjust the version in the poms, manifests and other eclipse stuff:

      $ droolsjbpm-build-bootstrap/script/release/update-version-all.sh 5.2.0.Final 5.2.0.Final  5.3.0-SNAPSHOT 5.3.0.SNAPSHOT 5.1.0.Final 5.1.0.Final 5.2.0-SNAPSHOT 5.2.0.SNAPSHOT
    

    • Commit those changes:

        $ droolsjbpm-build-bootstrap/script/git-all.sh commit -m"Set next development version: 5.3.0-SNAPSHOT"
      

    • Push all changes, both the first and the last version change commit, to the repository together:

        $ droolsjbpm-build-bootstrap/script/git-all.sh push
      

• Push the local tag to the remote blessed repository.

    $ droolsjbpm-build-bootstrap/script/release/git-push-tag-all.sh 5.2.0.Final 5.1.0.Final
  

• Release your staging repository on nexus

  • Button release

• Go to jira and for each of our JIRA projects (JBRULES, GUVNOR, JBPM):

  • Open menu item Administration, link Manage versions, release the version.

  • Create a new version if needed. There should be at least 2 unreleased non-FUTURE versions.

• Upload the zips, documentation and javadocs and update the website.

  • Go to droolsjbpm-build-distribution/droolsjbpm-uber-distribution/target.

  • download_jboss_org goes into download.jboss.org

    • Update the download webpage accordingly

  • docs_jboss_org goes into docs.jboss.org

    • Use documentation_table.txt to update the documentation webpage.

Announcing the the release

• Create a blog entry on the droolsjbpm blog

  • Include a direct link to the new and noteworthy section and to that blog entry in all other correspondence.

  • Twitter and Google+ the links.

    • Most people just want to read the new and noteworthy, so link that first.

  • Mail the links to the user list.

• If it's a final release:

  • Notify TheServerSide and Dzone's Daily Dose.

FAQ

• Why do you not accept @author lines in your source code?

  • Because the author tags in the java files are a maintenance nightmare

    • A large percentage is wrong, incomplete or inaccurate.

    • Most of the time, it only contains the original author. Many files are completely refactored/expanded by other authors.

    • Git is accurate, that is the canonical source to find the correct author.

  • Because the author tags promote code ownership, which is bad in the long run.

    • If people work on a piece they perceive as being owned by someone else, they tend to:

      • only fix what they are assigned to fix, instead of everything that's broken

      • discard responsibility if that code doesn't work properly

      • be scared of stepping on the feet of the owner.

    • For more motivation, see this video on How to get a healthy open source project?

  • Credit to the authors is given:

    • on the team page

      • Please contact Geoffrey (or any of us) if you want to add/change/expand your entry in the team page. Don't be shy!

    • on the blog

      • Write an article about the improvements you did! Contact us if you don't have write authorization on the blog yet.

    • with ohloh which also has statistics

    • in the github web interface.