Ok, so I had a whole bunch of work to do today and I\’ve just thrown it out the window: Google has unleashed Java support for Google App Engine.
This is huge news. The implementation is solid (it does its best, within the restrictions of Google\’s architecture, to support standards and avoid architectural lock-in).
Let\’s cut to the chase: I spent this afternoon working out how to build App Engine Java projects with Maven 2 instead of Ant.
I do this for several reasons, the main one being that the CMS I\’m building uses Maven as a build system and I love it. A secondary reason is that Maven easily gives me the power to target OSGI, App Engine, and plain ol\’ Java Servlets with the one project.
So here we go. First, here\’s a script to install some of Google\’s more obscure libraries into your local Maven repository:
#!/bin/sh
#install Google App Engine dependencies into local maven repository
#copyright 2009 Gravity Rail Pty Ltd
export CURR=`pwd`
export SDK=`pwd`
export LIB="${SDK}/lib"
export VERS="1.2.0"
cd $LIB
mvn install:install-file -Dfile=${LIB}/appengine-tools-api.jar
-DgroupId=com.google
-DartifactId=appengine-tools
-Dversion=${VERS}
-Dpackaging=jar
-DgeneratePom=true
mvn install:install-file -Dfile=${LIB}/shared/appengine-local-runtime-shared.jar
-DgroupId=com.google
-DartifactId=appengine-tools
-Dversion=${VERS}
-Dpackaging=jar
-DgeneratePom=true
mvn install:install-file -Dfile=${LIB}/shared/geronimo-el_1.0_spec-1.0.1.jar
-DgroupId=org.apache.geronimo.specs
-DartifactId=geronimo-el_1.0_spec
-Dversion=1.0.1
-Dpackaging=jar
-DgeneratePom=true
mvn install:install-file -Dfile=${LIB}/shared/geronimo-jsp_2.1_spec-1.0.1.jar
-DgroupId=org.apache.geronimo.specs
-DartifactId=geronimo-jsp_2.1_spec
-Dversion=1.0.1
-Dpackaging=jar
-DgeneratePom=true
mvn install:install-file -Dfile=${LIB}/shared/geronimo-servlet_2.5_spec-1.2.jar
-DgroupId=org.apache.geronimo.specs
-DartifactId=geronimo-servlet_2.5_spec
-Dversion=1.2
-Dpackaging=jar
-DgeneratePom=true
mvn install:install-file -Dfile=${LIB}/user/orm/geronimo-jpa_3.0_spec-1.1.1.jar
-DgroupId=org.apache.geronimo.specs
-DartifactId=geronimo-jpa_3.0_spec
-Dversion=1.1.1
-Dpackaging=jar
-DgeneratePom=true
mvn install:install-file -Dfile=${LIB}/user/orm/geronimo-jta_1.1_spec-1.1.1.jar
-DgroupId=org.apache.geronimo.specs
-DartifactId=geronimo-jta_1.1_spec
-Dversion=1.1.1
-Dpackaging=jar
-DgeneratePom=true
mvn install:install-file -Dfile=${LIB}/user/orm/datanucleus-appengine-1.0.0.final.jar
-DgroupId=org.datanucleus
-DartifactId=datanucleus-appengine
-Dversion=1.0.0.final
-Dpackaging=jar
-DgeneratePom=true
cd $CURR
Next, let\’s modify the ant build.xml file in the root of our project slightly to take account of Maven\’s default project layout:
Finally, we put in our pom.xml file that calls ant for tasks like deployment (doesn\’t quite work yet):
4.0.0
com.transitplatform
TransitAppEngine
war
Transit App Engine
1.0-SNAPSHOT
war/WEB-INF/classes
src/main/resources
src/main/java
**
**/*.java
maven-compiler-plugin
1.6
maven-antrun-plugin
1
compile
run
2
deploy
run
org.apache.wicket
wicket
1.4-rc2
org.apache.geronimo.specs
geronimo-jsp_2.1_spec
1.0.1
org.apache.geronimo.specs
geronimo-jpa_3.0_spec
1.1.1
org.apache.geronimo.specs
geronimo-jpa_3.0_spec
1.1.1
ant
ant
1.6.5
ant
ant-launcher
1.6.5
commons-logging
commons-logging
1.1.1
commons-el
commons-el
1.0
org.datanucleus
datanucleus-core
1.1.0
javax.transaction
transaction-api
org.datanucleus
datanucleus-jpa
1.1.0
org.datanucleus
datanucleus-appengine
1.0.0.final
tomcat
jasper-compiler
5.0.28
tomcat
jasper-runtime
5.0.28
javax.jdo
jdo2-api
2.3-SNAPSHOT
javax.transaction
transaction-api
javax.transaction
jta
1.1
org.slf4j
jcl104-over-slf4j
1.4.3
org.slf4j
slf4j-simple
1.4.3
datanucleus
Datanucleus Repository
http://www.datanucleus.org/downloads/maven2/
Hope you find this useful, and good luck! Also, let me know if you have any corrections, compliments, duffel-bags-full-of-cash, etc.
Download a sample project here:
Your POM formatting is bust, can you put in a pre tag or something?
I’m a bit confused about what the output is. You aim is to use Maven layout for Java and resource sources, and Google layout for the war content? FWFIW I tried that and it works with the Eclipse tooling as well.
Dan,
Quick stuff on getting the maven structure set up, but your page doesn’t seem to be rendering right to follow the example. I’ve tried Firefox, IE, and Opera with no success!
James
I have just created a simple HelloWorld application using maven 2 which can be deployed to Google App Engine with simple command “mvn install”
Anyone who is interested can download it from
http://winkjava.110mb.com/gaehelloworld/helloworld.zip
Happy hacking!
Here is a batch file for windows to do the gae artifact local maven repo installing:
set LIB=d:downloadsappengine-java-sdk-1.2.0lib
set VERS=1.2.0
call mvn install:install-file -Dfile=%LIB%/appengine-tools-api.jar -DgroupId=com.google -DartifactId=appengine-tools -Dversion=%VERS% -Dpackaging=jar -DgeneratePom=true
call mvn install:install-file -Dfile=%LIB%/shared/appengine-local-runtime-shared.jar -DgroupId=com.google -DartifactId=appengine-tools -Dversion=%VERS% -Dpackaging=jar -DgeneratePom=true
call mvn install:install-file -Dfile=%LIB%/shared/geronimo-el_1.0_spec-1.0.1.jar -DgroupId=org.apache.geronimo.specs -DartifactId=geronimo-el_1.0_spec -Dversion=1.0.1 -Dpackaging=jar -DgeneratePom=true
call mvn install:install-file -Dfile=%LIB%/shared/geronimo-jsp_2.1_spec-1.0.1.jar -DgroupId=org.apache.geronimo.specs -DartifactId=geronimo-jsp_2.1_spec -Dversion=1.0.1 -Dpackaging=jar -DgeneratePom=true
call mvn install:install-file -Dfile=%LIB%/shared/geronimo-servlet_2.5_spec-1.2.jar -DgroupId=org.apache.geronimo.specs -DartifactId=geronimo-servlet_2.5_spec -Dversion=1.2 -Dpackaging=jar -DgeneratePom=true
call mvn install:install-file -Dfile=%LIB%/user/orm/geronimo-jpa_3.0_spec-1.1.1.jar -DgroupId=org.apache.geronimo.specs -DartifactId=geronimo-jpa_3.0_spec -Dversion=1.1.1 -Dpackaging=jar -DgeneratePom=true
call mvn install:install-file -Dfile=%LIB%/user/orm/geronimo-jta_1.1_spec-1.1.1.jar -DgroupId=org.apache.geronimo.specs -DartifactId=geronimo-jta_1.1_spec -Dversion=1.1.1 -Dpackaging=jar -DgeneratePom=true
call mvn install:install-file -Dfile=%LIB%/user/orm/datanucleus-appengine-1.0.0.final.jar -DgroupId=org.datanucleus -DartifactId=datanucleus-appengine -Dversion=1.0.0.final -Dpackaging=jar -DgeneratePom=true
Here is a batch file for windows to do the gae artifact local maven repo installing:
Vote here if you are looking for maven support in GAE
http://code.google.com/p/googleappengine/issues/detail?id=1296