Spring 3 + maven2 + Google App Engine: Part 2 [POM Setup]

In this post, we will look at the POM file and the dependencies for not only a solid web application using Spring 3, but the dependencies specific to Google App Engine. This is not meant to be a comprehensive overview of Maven and may or may not use best practices for Maven (ie, I'll ignore comments about your maven file, grab a maven book, hopefully off the links to the right!)

Now, let's take a look at the POM file and setup our project.  We need to add the Google App Engine and the related dependencies, DataNucleus for enhancing domain objects (though, I am investigating how to use Spring persistence through Annotations to replace this dependency), JUnit and various other utilities needed to construct a working web-app.

Most of the POM file generated from part 1 will be sufficient, but we need to start adding dependencies. We'll start with the Spring 3.

Inside of your <dependencies> section, lets add the following dependencies:

Project Dependencies

Spring 3

 
        <dependency>
            <groupid>org.springframework</groupid>
            <artifactid>spring-webmvc</artifactid>
            <version>3.0.1.RELEASE</version>
        </dependency>

        <dependency>
            <groupid>org.springframework</groupid>
            <artifactid>spring-test</artifactid>
            <version>3.0.1.RELEASE</version>
        </dependency>

Google App Engine

 
        <dependency>
            <groupId>com.google.appengine</groupId>
            <artifactId>datanucleus-jpa</artifactId>
            <version>1.1.5</version>
            <scope>runtime</scope>
        </dependency>

        <dependency>
            <groupId>com.google.appengine</groupId>
            <artifactId>geronimo-jpa_3.0_spec</artifactId>
            <version>1.1.1</version>
            <scope>runtime</scope>
        </dependency>

        <dependency>
            <groupId>com.google.appengine</groupId>
            <artifactId>appengine-api-1.0-sdk</artifactId>
            <version>1.3.2</version>
        </dependency>

        <dependency>
            <groupId>com.google.appengine</groupId>
            <artifactId>appengine-api-labs</artifactId>
            <version>1.3.2</version>
            <scope>test</scope>
        </dependency>

        <dependency>
            <groupId>com.google.appengine</groupId>
            <artifactId>appengine-api-stubs</artifactId>
            <version>1.3.2</version>
            <scope>test</scope>
        </dependency>

        <dependency>
            <groupId>com.google.appengine</groupId>
            <artifactId>appengine-testing</artifactId>
            <version>1.3.2</version>
            <scope>test</scope>
        </dependency>

        <dependency>
            <groupId>com.google.appengine</groupId>
            <artifactId>appengine-local-runtime</artifactId>
            <version>1.3.2</version>
            <scope>test</scope>
        </dependency>

Google App Engine Data Store

 
        <dependency>
            <groupId>javax.jdo</groupId>
            <artifactId>jdo2-api</artifactId>
            <version>2.3-eb</version>
            <exclusions>
                <exclusion>
                    <groupId>javax.transaction</groupId>
                    <artifactId>transaction-api</artifactId>
                </exclusion>
            </exclusions>
        </dependency>

        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>jstl</artifactId>
            <version>1.2</version>
            <type>jar</type>
            <scope>provided</scope>
        </dependency>

        <dependency>
            <groupId>javax.transaction</groupId>
            <artifactId>jta</artifactId>
            <version>1.1</version>
        </dependency>

        <dependency>
            <groupId>com.google.appengine.orm</groupId>
            <artifactId>datanucleus-appengine</artifactId>
            <version>1.0.5.final</version>
        </dependency>

        <dependency>
            <groupId>org.datanucleus</groupId>
            <artifactId>datanucleus-core</artifactId>
            <version>1.1.5</version>
            <exclusions>
                <exclusion>
                    <groupId>javax.transaction</groupId>
                    <artifactId>transaction-api</artifactId>
                </exclusion>
            </exclusions>
        </dependency>

Now you have the default minimum dependencies for GAE (still not there quite yet, we need to add the necessary plugins). If you are more familiar with Maven, you might want to add in Ant, Apache Commons Collections and any other libraries you typically use.

Plugins
Once you have the needed libraries it is time to setup the plugins to build and run your project.  Add the following to the section:

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-war-plugin</artifactId>
    <version>2.1-alpha-2</version>
    <configuration>
        <webAppConfig>
            <contextPath>/movie</contextPath>
            <scanIntervalSeconds>10</scanIntervalSeconds>
        </webAppConfig>
        <webResources>
            <resource>
                <directory>src/main/webapp</directory>
                <filtering>true</filtering>
                <includes>
                    <include>**/appengine-web.xml</include>
                </includes>
            </resource>
        </webResources>
    </configuration>
</plugin>

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-compiler-plugin</artifactId>
    <configuration>
        <source>1.6</source>
        <target>1.6</target>
    </configuration>
</plugin>

<plugin>
    <groupId>org.codehaus.mojo</groupId>
    <artifactId>cobertura-maven-plugin</artifactId>
    <version>${cobertura-version}</version>
    <executions>
        <execution>
            <goals>
                <goal>clean</goal>
            </goals>
        </execution>
    </executions>
</plugin>

<plugin>
    <groupId>org.datanucleus</groupId>
    <artifactId>maven-datanucleus-plugin</artifactId>
    <version>1.1.4</version>
    <configuration>
        <!-- Make sure this path contains your persistent classes! -->
        <mappingIncludes>**/model/*.class</mappingIncludes>
        <!-- */This is where your domain objects will be located -->
        <verbose>true</verbose>
        <enhancerName>ASM</enhancerName>
        <api>JDO</api>
    </configuration>
    <executions>
        <execution>
            <phase>compile</phase>
            <goals>
                <goal>enhance</goal>
            </goals>
        </execution>
    </executions>
    <dependencies>
        <dependency>
            <groupId>org.datanucleus</groupId>
            <artifactId>datanucleus-core</artifactId>
            <version>1.1.5</version>
            <exclusions>
                <exclusion>
                    <groupId>javax.transaction</groupId>
                    <artifactId>transaction-api</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <groupId>org.datanucleus</groupId>
            <artifactId>datanucleus-rdbms</artifactId>
            <version>1.1.5</version>
        </dependency>
        <dependency>
            <groupId>org.datanucleus</groupId>
            <artifactId>datanucleus-enhancer</artifactId>
            <version>1.1.4</version>
        </dependency>
    </dependencies>
</plugin>

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-surefire-plugin</artifactId>
    <version>${maven-surefire-plugin-version}</version>
    <configuration>
        <includes>
            <include>**/*Spec.java</include>
            <include>**/*Test.java</include>
        </includes>
    </configuration>
</plugin>
<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-jxr-plugin</artifactId>
</plugin>

<plugin>
    <groupId>net.kindleit</groupId>
    <artifactId>maven-gae-plugin</artifactId>
    <version>0.5.2</version>
    <configuration>
        <unpackVersion>1.3.2</unpackVersion>
    </configuration>
</plugin>

<plugin>
    <artifactId>maven-release-plugin</artifactId>
    <configuration>
        <goals>gae:deploy</goals>
    </configuration>
</plugin>

<plugin>
    <artifactId>maven-antrun-plugin</artifactId>
    <executions>
        <execution>
            <phase>compile</phase>
            <configuration>
                <tasks>

                    <!--
                        This creates the META-INF folder inside of classes, then
                        copies over the jdoconfig.xml required for GAE
                    -->
                    <mkdir dir="${project.build.directory}/classes/META-INF"/>
                    <copy file="${project.build.directory}/classes/jdoconfig.xml"
                          todir="${project.build.directory}/classes/META-INF" />
                    <echo message="Copy:${project.build.directory}/classes/jdoconfig.xml to " />
                    <echo message="${project.build.directory}/classes/META-INF"/>
                </tasks>
            </configuration>
            <goals>
                <goal>run</goal>
            </goals>
        </execution>
    </executions>
</plugin>

Click here to get the full pom.xml file