CloudStack Volume Provider Adaptive Plugin Base

The Adaptive Plugin Base is an abstract volume storage provider that provides a generic implementation for managing volumes that are exposed to hosts through FiberChannel and similar methods but managed independently through a storage API or interface. The ProviderAdapter, and associated classes, provide a decoupled interface from the rest of Cloudstack that covers the exact actions needed to interface with a storage provider. Each storage provider can extend and implement the ProviderAdapter without needing to understand the internal logic of volume management, database structure, etc.

Implement the Provider Interface

To implement a provider, create another module -- or a standalone project -- and implement the following interfaces from the org.apache.cloudstack.storage.datastore.adapter package:

1. ProviderAdapter - this is the primary interface used to communicate with the storage provider when volume management actions are required.
2. ProviderAdapterFactory - the implementation of this class creates the correct ProviderAdapter when needed.

Follow Javadoc for each class on further instructions for implementing each function.

Implement the Primary Datastore Provider Plugin

Once the provider interface is implemented, you will need to extend the org.apache.cloudstack.storage.datastore.provider.AdaptiveProviderDatastoreProviderImpl class. When extending it, you simply need to implement a default constructor that creates an instance of the ProviderAdapterFactory implementation created in #2 above. Once created, you need to call the parent constructor and pass the factory object.

Provide the Configuration for the Provider Plugin

Lastly, you need to include a module file and Spring configuration for your Primary Datastore Provider Plugin class so Cloudstack will load it during startup.

Module Properties

This provides the hint to Cloudstack to load this as a module during startup.

#resources/META-INF/cloudstack/storage-volume-<providername>/module.properties
name=storage-volume-<providername>
parent=storage

Spring Bean Context Configuration

This provides instructions of which provider implementation class to load when the Spring bean initilization is running.

<!-- resources/META-INF/cloudstack/storage-volume-<providername>/spring-storage-volume-<providername>-context.xml -->
<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:aop="http://www.springframework.org/schema/aop"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
                      http://www.springframework.org/schema/beans/spring-beans.xsd
                      http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd
                      http://www.springframework.org/schema/context
                      http://www.springframework.org/schema/context/spring-context.xsd"
                      >

    <bean id="<providername>DataStoreProvider"
        class="org.apache.cloudstack.storage.datastore.provider.<providername>PrimaryDatastoreProviderImpl">
	  </bean>
</beans>

Build and Deploy the Jar

Once you build the new jar, start Cloudstack Management Server or, if a standalone jar, add it to the classpath before start. You should now have a new storage provider of the designated name once Cloudstack finishes loading all configured modules.