LavaJUG-Maven 3.x, will it lives up to its promises

Apache Maven 3.x W I L L I T L I V E U P TO I T S P R O M I S E S ?

L A V A J U G - J U N E 2 0 1 2

Arnaud Héritier Software Factory Manager

www.exoplatform.com - Copyright 2012 eXo Platform 2

ARNAUD HÉRIT IER

−  eXo - Software Factory Manager −  In charge of tools and

methods −  Apache Maven :

−  Committer since 2004 and member of the Project Management Committee

−  Coauthor of « Apache Maven» −  published by Pearson (in

French) −  Contact me :

−  http://aheritier.net −  Twitter : @aheritier −  Skype : aheritier


1

2

3

4 −  Questions

−  Why Apache Maven?

−  Apache Maven 3.x, Where are we, where are we going to … −  Community, Resources, −  Backward Compatibility, Performances, Extensibility, Robustness, Pom

−  Tesla −  What is it ?

Why ? A PA C H E M AV E N ( 3 . X )


DEFINIT ION

−  Apache Maven is a software project management and comprehension tool.

−  Based on the concept of a project object model (POM) −  can manage a project's build, binaries, reporting and documentation

from a central piece of information.

−  Apache Maven is standards/conventions driven −  How many of you are doing JEE and related developments ?


HISTORY

−  Initiated in 2001 by Jason Van Zyl in Alexandria, an Apache Jakarta project,

−  Moved to Turbine few months after,

−  Became a Top Level Project in 2003.

−  2.0 released in September 2005

−  3.0 released in October 2010 −  3.0.4 – January 2012


CHOOSE YOUR WAY OF THINKING

Conventions approach Scripting approach


COMPETITORS ( IN JAVA LAND)

−  Ant + Ivy, Easy Ant, Gant, Gradle, Buildr…

−  Script oriented −  You can do what you want !

−  Reuse many of conventions (directories layout, …) and services (repositories) but without enforcing them

−  The risk for them : Not being able to evolve due to the too high level of customization proposed to the user. −  We tried on 1 and it died because of that. It was impossible to create a

set of tests to cover all usages. −  It’s like providing a framework without a well tested set of public API L


WITH SCRIPTS ORIENTED BUILDS

You can have (if you have good skills)

But often you have (moreover after years …)


WITH MAVEN

We dream to deliver (Maven 3.x)

But yesterday we too often had (Maven 2.x)

Where are we ? Where are we going to ? A PA C H E M AV E N 3 . X


COMMUNITY Apache Maven 3.x


USERS MAIL ING L IST

−  [email protected] −  Traffic statistics cover a total

of 2338 days (>6y). −  Current subscribers: 1902 −  Total posts: 95442 −  Mean posts per day: 40.82

−  http://pulse.apache.org/

−  Blue : −  Number of subscribers

−  Red : −  Number of messages per day


DEV MAIL ING L IST

−  [email protected] −  Traffic statistics cover a total

of 2338 days (>6y). −  Current subscribers: 676 −  Total posts: 63215 −  Mean posts per day: 27,04

−  http://pulse.apache.org/

−  Blue : −  Number of subscribers

−  Red : −  Number of messages per day


APACHE MAVEN WEB SITE


APACHE MAVEN WEB SITE


DOWLOADS

−  Per month downloads

−  http://people.apache.org/~vgritsenko/stats/projects/maven.html


RELEASES (LAST 2 MONTHS)

−  Plugins −  Compiler 2.5.1 (2012-06-04) −  Changes 2.7.1 (2012-05-10) −  Shade 1.7 (2012-06-01) −  Compiler 2.5 (2012-05-27) −  Clean 2.5 (2012-05-26) −  Release 2.3.1 (2012-05-25) −  Invoker 1.6 (2012-05-24) −  Remote Resources 1.3

(2012-05-11) −  Release 2.3 (2012-05-11) −  Site 3.1 (2012-04-30) −  Changes 2.7 (2012-04-30) −  Compiler 2.4 (2012-04-30) −  Site 2.4 (2012-04-26)

−  Libraries −  Tools 3.0 (2012-05-31) −  Runtime 1.0-alpha-3

(2012-05-28) −  Testing 2.0 (2012-05-27) −  Enforcer 1.1 (2012-05-14) −  SCM 1.7 (2012-04-29) −  Doxia (base) 1.3 (2012-04-13) −  Doxia Sitetools 1.3

(2012-04-17)


THE COMMUNITY

−  ~20 PMC, ~20 committers, ~20 emeritus −  A community less isolated : more interactions with Eclipse,

Jetty, …

−  A new French PMC Chair in few days : Olivier Lamy (Cocorico !!!)


RESOURCES Apache Maven 3.x


BOOKS

−  Nicolas De loof Arnaud Héritier −  Published by Pearson −  Collection Référence −  Based on our own

experiences with Maven. −  From beginners to experts. −  In French only


BOOKS

−  Sonatype / O’Reilly : −  The Definitive Guide −  http://www.sonatype.com/

books −  Free download −  Available in several

languages


BOOKS

−  Apache Maven 2 Effective Implementation −  Brett Porter, Maria Odea

Ching −  https://www.packtpub.com/

apache-maven-2-effective-implementation/book


BOOKS

−  Exist Global −  Better builds with Maven −  http://www.maestrodev.com/

better-build-maven −  Free download


MANY OTHERS RESOURCES

−  Many companies are providing trainings and expertise

−  Many resources on internet (blogs, ….)

−  The main web site : −  http://maven.apache.org

−  Project’s team wiki : −  http://docs.codehaus.org/display/MAVEN

−  Project’s users wiki : −  http://docs.codehaus.org/display/MAVENUSER

−  Mailing lists

−  http://maven.apache.org/mail-lists.html

−  IRC −  irc.codehaus.org - #maven

−  Forums −  developpez.net (In French) −  Stackoverflow


BACKWARD COMPATIBILITY Apache Maven 3.x


BACKWARD COMPATIBIL ITY CRIT ICISMS

−  Migration from Maven 1 to 2 was impossible. Everything had to be re-done.

−  Updates between 2.x versions and also between 2.0.x weren’t too often without side effects.


BACKWARD COMPATIBIL ITY

−  Near to 700 integration tests

−  Tested for several months on a large set of OSS projects

−  7 alphas + 3 betas versions −  It’s a revolution under the hood but an evolution for end users


MAVEN 3 .0 .X ITS

674


PERFORMANCES Apache Maven 3.x


PERFORMANCES - CRIT ICISMS

−  Maven is slow

−  It spends its time to download the world

−  Whereas everybody has multicore CPUs, it doesn’t allow to process tasks in parallel


PERFORMANCES

−  A set of benchmark tools was developed to measure performances (IO, CPU, Memory, Network …)

−  Startup and execution times are reduced −  Java 5 optimizations −  Code cleanup and improvements

−  Reduced Memory footprint

−  Artifacts Resolution Caching −  .lastUpdated files in your local repo −  Enforce checks with –U option


PERFORMANCES – PARALLEL BUILDS

−  Parallel builds −  An execution plan is predefined at startup to define which modules

could be built in // −  Requires to have up to date plugins to avoid dead locks and some

others issues −  Launch a build with 2 threads

− mvn –T 2 install −  Launch a build with 2 threads per CPU core

− mvn –T 2C install


PERFORMANCES - PLUGINS

−  Many improvements in plugins −  In Surefire/Failsafe to propose various strategies to execute tests in //

and to order them −  In Compiler to keep loaded the classloader used by Javac −  In Packaging plugins (Assembly, Jar, War, …) by improving

performances in low level libraries (plexus …)


EXTENSIBILITY Apache Maven 3.x


EXTENSIBIL ITY - CRIT ICISMS

−  It is difficult and time consuming to extend Maven (write plugins) −  Many unknown technologies like Plexus for IOC

−  It is difficult/impossible to reuse Maven plugins −  Its impossible to extend plugins/mojo and lifecycles


EXTENSIBIL ITY

−  New APIs to improve abstraction of underneath implementation −  Aether : to manage artifacts and repositories

−  Classloader partitioning

−  Embeddable

−  IOC replaced by Guice −  For now (Maven 3.0) a wrapper is hiding the change −  You don’t yet use Guice directly (from plugins for example)


ROBUSTNESS Apache Maven 3.x


ROBUSTNESS - CRIT ICISMS

−  Builds aren’t predictable

−  Errors are difficult to diagnose


ROBUSTNESS - VALIDATIONS

−  Many more validations in POMs (warnings or errors) −  Missing plugins versions −  Duplicated dependencies in a POM −  Incoherent inheritance (wrong relative path or parent not in the upper

directory)

−  Improved error messages with links to wiki pages for more detailed information


ROBUSTNESS ARTIFACTS MANAGEMENT

−  Parent POMs prefer to resolve from repositories −  Version less parent will be available in a future 3.x release by using the

relativePath element

−  Profiles usage consolidation −  No more profiles.xml (incompatible with future polyglot feature)


ROBUSTNESS ARTIFACTS MANAGEMENT

−  No more support for legacy repository layout for Maven 1.0

−  SNAPSHOTs are always deployed with timestamps


ROBUSTNESS PLUGINS MANAGEMENT

−  version is by default RELEASE and no more SNAPSHOT −  Affects command-line invocation

−  Plugins cannot use versions LATEST or RELEASE −  Affects command-line invocation and POM

−  Plugins are resolved only from <pluginRepository> entries


ROBUSTNESS – S ITE PLUGIN

−  Site is now completely extracted from core −  It has its own lifecycle −  reporting section in POM becomes useless (moved in configuration)


POM Apache Maven 3.x


CRIT ICISMS

−  XML, we don’t like it

−  POM is too verbose

−  POM v4 didn’t evolve last 5 years −  When will you add new common attributes to ease plugins

configuration (encoding …) −  New feature like global exclusions


POM

−  No change in POM syntax for 3.0.x

−  Changes will occur in 3.x versions −  New model with a new version −  Only new things −  Generation / deployment of 4.0.0 current POM to keep backward

compatibility with old versions

−  Mixins to allow to import POM fragments

Tesla W H AT I S I T ?


WHAT! YOU FORKED APACHE MAVEN?


A FORK OF APACHE MAVEN ?

−  “The build portion of Tesla are extensions to Maven. The small differences in the core I currently have will be contributed back.” - Jason van Zyl

−  “It’s fork as long as Apache Maven core differences aren’t proposed to be contributed back AND validated by the Apache Maven team” – Arnaud and others Apache Maven members


WHAT IS TESLA ?

−  A new project leaded by Jason Van Zyl

−  Sources are on Github : https://github.com/etesla

−  License : Eclipse Public License v1.0

−  “It is not just about builds. Build, IDE, CI, repository management and provisioning.” - Jason Van Zyl

−  It is a set of extensions on top of existing tools : Apache Maven, M2E, Nexus, Hudson, …


FEATURES

−  Local repository: −  Concurrent Local Repository −  Automatic Local Snapshot Purging −  Split Local Repository

−  Polyglot Support

−  development: −  Java 5 Annotation-based API −  JSR-330 (DI) Components in Plugins

−  Build Avoidance API

−  Several New Extension Points

−  TeslaShell

−  More to come!

In Apache since few weeks too


AUTOMATIC LOCAL SNAPSHOT PURGING


POLYGLOT SUPPORT


TESLA SHELL


TESLA SHELL

Thank You Q U E S T I O N S ?


LICENCE ET COPYRIGHTS

−  Photos and logos belong to their respective authors/owners

−  Various ideas are coming from the excellent presentation done by Matthew McCullough : −  http://www.slideshare.net/matthewmccullough/maven-30-at-oredev

−  Tesla details are coming from Anders Hammar’s presentation for Jfocus 2012 −  http://goo.gl/XNPpQ


LICENCE ET COPYRIGHTS

−  Content under Creative Commons 3.0 −  Attribution — You must attribute the work in the manner specified by

the author or licensor (but not in any way that suggests that they endorse you or your use of the work).

−  Noncommercial — You may not use this work for commercial purposes. −  Share Alike — If you alter, transform, or build upon this work, you may

distribute the resulting work only under the same or similar license to this one.

− http://creativecommons.org/licenses/by-nc-sa/3.0/us/

Technology

LavaJUG-Maven 3.x, will it lives up to its promises