Using the Migration Data Adapter

###Configuring Atom Hopper to use the Migration Data Adapter###

The Migration data adapter ships with Atom hopper version 1.2.0 and above.

Note: Please note that the Migration Data Adapter is currently in the stage of ongoing development.

You can turn on the Migration data adapter easily following these steps:

• Edit the application-context.xml file so it looks similar to the following (edit as needed to suit your particular needs). This example shows someone migrating from a database schema used in the original Hibernate Data Adapter to a database schema used in the new Postgres Data Adapter.

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:mongo="http://www.springframework.org/schema/data/mongo"
       xsi:schemaLocation="http://www.springframework.org/schema/context 
                           http://www.springframework.org/schema/context/spring-context-3.0.xsd
                           http://www.springframework.org/schema/beans 
                           http://www.springframework.org/schema/beans/spring-beans-3.0.xsd">

    <bean name="feed-repository-bean" class="org.atomhopper.hibernate.HibernateFeedRepository">
        <constructor-arg>
            <map>
                 <entry key="hibernate.connection.driver_class" value="org.postgresql.Driver" />
                 <entry key="hibernate.dialect" value="org.hibernate.dialect.PostgreSQLDialect" />
                 <entry key="hibernate.connection.url" value="jdbc:postgresql://localhost:5432/atomhopperold" />
                 <entry key="hibernate.connection.username" value="username" />
                 <entry key="hibernate.connection.password" value="password" />
            </map>
        </constructor-arg>
    </bean>

    <bean name="hibernate-feed-publisher"
           class="org.atomhopper.hibernate.adapter.HibernateFeedPublisher">
        <property name="feedRepository" ref="feed-repository-bean" />
        <property name="allowOverrideId">
            <value>true</value>
        </property>
        <property name="allowOverrideDate">
            <value>true</value>
        </property>
    </bean>

    <bean name="hibernate-feed-source" class="org.atomhopper.hibernate.adapter.HibernateFeedSource">
        <property name="feedRepository" ref="feed-repository-bean" />
    </bean>

    <bean id="atomHopperDataSource" class="org.apache.commons.dbcp.BasicDataSource">
        <property name="driverClassName" value="org.postgresql.Driver" />
        <property name="url" value="jdbc:postgresql://localhost:5432/atomhoppernew" />
        <property name="username" value="username" />
        <property name="password" value="password" />
        <property name="minIdle" value="10" />
        <property name="maxIdle" value="25" />
        <property name="initialSize" value="10" />
        <property name="maxActive" value="50" />
    </bean>

    <bean name="atomHopperJdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
        <constructor-arg name="dataSource" ref="atomHopperDataSource"/>
    </bean>

    <bean name="postgres-feed-publisher" class="org.atomhopper.postgres.adapter.PostgresFeedPublisher">
        <property name="jdbcTemplate" ref="atomHopperJdbcTemplate" />
        <property name="allowOverrideId">
            <value>true</value>
        </property>
        <property name="allowOverrideDate">
            <value>true</value>
        </property>
    </bean>

    <bean name="postgres-feed-source" class="org.atomhopper.postgres.adapter.PostgresFeedSource">
        <property name="jdbcTemplate" ref="atomHopperJdbcTemplate" />  
    </bean>

    <bean name="migration-feed-publisher" class="org.atomhopper.migration.adapter.MigrationFeedPublisher">
        <property name="oldFeedPublisher" ref="hibernate-feed-publisher" />
        <property name="newFeedPublisher" ref="postgres-feed-publisher" />
        <property name="writeTo">
            <value>BOTH</value>
        </property>
        <property name="readFrom">
            <value>OLD</value>
        </property>
    </bean>

    <bean name="migration-feed-source" class="org.atomhopper.migration.adapter.MigrationFeedSource">
        <property name="oldFeedSource" ref="hibernate-feed-source" />
        <property name="newFeedSource" ref="postgres-feed-source" />
        <property name="readFrom">
            <value>OLD</value>
        </property>
    </bean>
</beans>

• NOTE: In order for the entries to have the same Id and LastUpdatedDate, the override properties on the feed publisher for both Data Adapters MUST to be set to true.

<bean name="hibernate-feed-publisher" class="org.atomhopper.hibernate.adapter.HibernateFeedPublisher">
    <property name="feedRepository" ref="feed-repository-bean" />
    <property name="allowOverrideId">
        <value>true</value>
    </property>
    <property name="allowOverrideDate">
        <value>true</value>
    </property>
</bean>

<bean name="postgres-feed-publisher" class="org.atomhopper.postgres.adapter.PostgresFeedPublisher">
    <property name="jdbcTemplate" ref="jdbcTemplate" />
    <property name="allowOverrideId">
        <value>true</value>
    </property>
    <property name="allowOverrideDate">
        <value>true</value>
    </property>
</bean>

• Edit the atom-server.cfg.xml file (by default the file is located in: /etc/atomhopper) so it looks similar to the following (edit as needed to suit your particular needs):

<?xml version="1.0" encoding="UTF-8"?>
 
<atom-hopper-config xmlns="http://atomhopper.org/atom/hopper-config/v1.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://atomhopper.org/atom/hopper-config/v1.0 ./../../config/atom-hopper-config.xsd">
    <defaults>
        <author name="Atom Hopper" />
    </defaults>
 
    <host domain="localhost:8080" />
 
    <workspace title="Testing Namespace" resource="/namespace/">
        <categories-descriptor reference="workspace-categories-descriptor" />
 
        <feed title="Testing Feed" resource="/feed">
            <publisher reference="migration-feed-publisher" />
            <feed-source reference="migration-feed-source" />
        </feed>
    </workspace>
</atom-hopper-config>

The important thing here is to ensure the following:

<publisher reference="migration-feed-publisher" />
<feed-source reference="migration-feed-source" />

Matches what is specified in the application-context.xml file.

<bean name="migration-feed-publisher" class="org.atomhopper.migration.adapter.MigrationFeedPublisher">
    <property name="oldFeedPublisher" ref="hibernate-feed-publisher" />
    <property name="newFeedPublisher" ref="postgres-feed-publisher" />
    <property name="writeTo">
        <value>BOTH</value>
    </property>
    <property name="readFrom">
        <value>OLD</value>
    </property>
</bean>
<bean name="migration-feed-source" class="org.atomhopper.migration.adapter.MigrationFeedSource">
    <property name="oldFeedSource" ref="hibernate-feed-source" />
    <property name="newFeedSource" ref="postgres-feed-source" />
    <property name="readFrom">
        <value>OLD</value>
    </property>
</bean>

If Atom Hopper is currently running you will need to restart it for the changes to take effect.