Why does Persistence.createEntityManagerFactory("transactions-optional") errors when appengine is deployed - google-app-engine

Question

I have created an appengine which runs fine and returns records from my Google cloud SQL db in debug mode. When I deploy the appegine and run the endpoint it errors. And the error I get in the appengine log is:
Caused by: org.datanucleus.exceptions.NucleusUserException: There is no available StoreManager of type "jdbc". Make sure that you have put the relevant DataNucleus store plugin in your CLASSPATH and if defining a connection via JNDI or DataSource you also need to provide persistence property "datanucleus.storeManagerType".
Here is a list or the jars in war\WEB-INF\lib directory:
appengine-api-1.0-sdk-1.7.6
appengine-api-labs
appengine-endpoints
appengine-jsr107cache-1.7.6
asm-4.0
com.sun.tools.xjc_2.2.0
com.sun.xml.bind_2.2.0.v201004141950
datanucleus-api-jdo-3.1.3
datanucleus-api-jpa-3.1.3
datanucleus-appengine-2.1.2
datanucleus-core-3.1.3
eclipselink
eclipselink-jpa-modelgen_2.4.1.v20121003-ad44345
gcm-server
geronimo-jpa_2.0_spec-1.0
javax.activation_1.1.0.v201108011116
javax.mail_1.4.0.v201005080615
javax.persistence_2.0.4.v201112161009
javax.xml.bind_2.2.0.v201105210648
javax.xml.stream_1.0.1.v201004272200
jdo-api-3.0.1
json_simple-1.1
jsr107cache-1.1
jta-1.1
org.eclipse.persistence.jpars_2.4.1.v20121003-ad44345
Here is my persistence.xml:
<persistence xmlns="http://java.sun.com/xml/ns/persistence"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/persistence
http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd" version="2.0">
<persistence-unit name="transactions-optional" transaction-type="RESOURCE_LOCAL">
<provider></provider>
<class>com.example.myapp.Class1</class>
<class>com.example.myapp.Class2</class>
<properties>
<property name="datanucleus.NontransactionalRead" value="true"/>
<property name="datanucleus.NontransactionalWrite" value="true"/>
<property name="javax.persistence.jdbc.driver" value="com.google.appengine.api.rdbms.AppEngineDriver"/>
<property name="javax.persistence.jdbc.url" value="jdbc:google:rdbms://something.com:someproj:someapp/somedb"/>
<property name="javax.persistence.jdbc.user" value=""/>
<property name="javax.persistence.jdbc.password" value=""/>
</properties>
</persistence-unit>
</persistence>
Using:
cloud sql
JPA
Datanucleous v2
SDK 1.7.6
Jre7
As it works fine in debug mode I dont understand what the problem might be as I am new to appengine. Please let me know if you need more information.
Thanks guys.

Answer 1

Make your mind up which JPA provider you're using ... for Cloud SQL (not AppEngine, so you don't need "datanucleus-appengine", nor do you need "datanucleus-api-jdo" either FWIW). You have DataNucleus JPA (version 3 actually, but omitting datanucleus-rdbms jar for some reason, yet CloudSQL needs it), and you have EclipseLink also. You then don't set the persistence provider in persistence.xml so leave it all to chance which one it tries to give you ... and it tries DataNucleus JPA but you haven't included the datanucleus-rdbms jar so you can't persist to an RDBMS without that.