Maven - setting up profiles and tokenizing properties file

Maven is a popular build tools and often you have a requirement to tokenize the name/value pairs in a properties file so that right values can be substituted depending on for which environment (local, dev, test, uat, prod) you are building the package for.


For example, your properties file (portal.properties) under DEV environment might look like

portal.rest.path.accounts=@PORTAL_REST_PATH_ACCOUNT_SERVICE@
portal.rest.path.tax=@PORTAL_REST_PATH_TAX_SERVICE@
portal.logout.url=@PORTAL_LOGOUT_URL@

The values within "@" are tokens that needs to be replaced at build time. The properties files reside under src/main/resources folder as per the Maven structure.Here is a sample DEV resource myapp.properties that sits under /env/dev folder.

PORTAL_REST_PATH_ACCOUNT_SERVICE=http://DEV-1:8080/accounts_service
PORTAL_REST_PATH_TAX_SERVICE=http://DEV-1:8080/tax_service
PORTAL_LOGOUT_URL=https://smlogin-dev.myapp.net/siteminderagent/ssologout/Logout.html

Next step is to configure the pom.xml file in Maven. This is done via the profiles as shown below.

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">

   ....

    <profiles>
  
  <profile>
   <id>dev-tomcat</id>
   <build>
    <resources>
     <resource>
      <directory>src/main/resources</directory>
      <filtering>true</filtering>
     </resource>
    </resources>
    <filters>
     <filter>env/dev/myapp.properties</filter>
    </filters>
   </build>
  </profile>
 </profiles>
 
 ....
 
</project>

    <build>
  <resources>
   <resource>
    <directory>src/main/resources</directory>
    <filtering>true</filtering>
   </resource>
  </resources>
 </build>

You also need to turn filtering on as shown below in the pom file.



Finally, you can invoke this profile with the -P option in the mvn command.

clean install tomcat:run -Dmaven.tomcat.port=8080 -Pdev-tomcat

There 3 types of Maven profiles.

• Per Project profile: Defined in the pom.xml file as shown above.
• Per User profile: Defined in Maven settings.xml file under %USER_HOME%/.m2
• Global profile: Defined in Maven global settings.xml file under %M2_HOME%/conf/

and these profiles can be activated a number of ways

1. Via command line with -P option as shown above.

2. You can activate it via the Maven settings.xml file as shown below

<settings xmlns="http://maven.apache.org/POM/4.0.0"
   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
   xsi:schemaLocation="http://maven.apache.org/POM/4.0.0
   http://maven.apache.org/xsd/settings-1.0.0.xsd">
   <mirrors>
      <mirror>
         <id>maven.dev.snaponglobal.com</id>
         <name>Internal Artifactory Maven repository</name>
         <url>http://repo1.maven.org/maven2/</url>
         <mirrorOf>*</mirrorOf>
      </mirror>
   </mirrors>
   <activeProfiles>
      <activeProfile>dev-tomcat</activeProfile>
   </activeProfiles>
</settings>

All you have to do is type mvn install and the dev-tomcat profile will be kicked off

3. Via environment variables.

<profile>
   <id>dev-tomcat</id>
   <activation>
      <property>
         <name>env</name>
         <value>dev-tomcat</value>
      </property>
   </activation>
</profile>

4. Via operating system (OS)

<profile>
   <id>test</id>
   <activation>
      <os>
         <name>Windows </name>
         <family>Windows</family>
         <arch>x86</arch>
         <version>6.1<version>
      </os>
   </activation>
</profile>

5. Based on a missing file

<profile>
   <id>test</id>
   <activation>
      <file>
         <missing>target/generated-sources/wsdl</missing>
      </file>
   </activation>
</profile>

Q. Can you give an example where you used a profile?
A. Firstly, to tokenize properties as demonstrated in the beginning of the post. Secondly, in local development you set up a datasource for your tomcat server to use as shown below.

    
 <profiles>
  <!-- Used for running tomcat locally to do application testing by substituting 
   tokenized variables from a properties file-->
  <profile>
   <id>dev-tomcat</id>
   <build>
    <resources>
     <resource>
      <directory>src/main/resources</directory>
      <filtering>true</filtering>
     </resource>
    </resources>
    <filters>
     <filter>src/main/filters/myapp.properties</filter>
    </filters>
    <plugins>
     <plugin>
      <groupId>org.codehaus.mojo</groupId>
      <artifactId>tomcat-maven-plugin</artifactId>
      <configuration>
          <!-- define your datasource here-->
       <contextFile>src/main/resources/tomcat-maven-plugin/context.xml</contextFile>
      </configuration>
     </plugin>
    </plugins>
   </build>
  </profile>
 </profiles>

The context.xml file will look like

<?xml version="1.0" encoding="ISO-8859-1"?>
<Context>
 <Resource
  name="jdbc/myapp_ds"
  type="javax.sql.DataSource"
  driverClassName="com.sybase.jdbc3.jdbc.SybDataSource"
  auth="Container"
  username="aes_service"
  password="service1"
  url="jdbc:sybase:Tds:myserver:5500/my_db?applicationname=myapp"
  initialSize="5"
  maxActive="5"
  maxIdle="1"
  minIdle="0"
  validationQuery="my_validateQuery"
  testOnBorrow="true"
  testOnReturn="false"
  testWhileIdle="false"
  poolPreparedStatements="false"
  removeAbandoned="false"
  logAbandoned="false"
   />
</Context>