Queries to a Property Provider Adapter accept one or more specific vSphere objects, and return one or more properties for those objects. A Property Provider Adapter registers with the Data Service to advertise which types of properties it can return. When the Data Service receives a query for one of the registered property types, the Data Service routes the query to the appropriate Property Provider Adapter for processing.

Note

You may not register a provider for an existing VMware property or object type. For example, if your solution needs to identify a host by an alternate name, you may create an adapter to implement a property such as alt_name, but it may not modify the original name property.

PropertyProviderAdapter Interface

A Property Provider Adapter must implement the PropertyProviderAdapter interface of the com.vmware.vise.data.query package. The PropertyProviderAdapter interface publishes a single method named getProperties(). Your Property Provider Adapter service must provide an implementation of this method. The Data Service calls the getProperties() method of your adapter in response to an appropriate query for the properties your adapter is registered to provide.

The method implementation in your service must accept as its parameter an object of type com.vmware.vise.data.query.PropertyRequestSpec, and must return an object of type com.vmware.vise.data.query.ResultSet. 

public ResultSet getProperties(PropertyRequestSpec propertyRequest)

Your service implementation of the getProperties() method can retrieve and format data in any way you choose. However, your implementation must return the results as a ResultSet object. You use the PropertyRequestSpec object to obtain the query list of target vSphere objects and desired properties. The PropertyRequestSpec object contains an objects array and a properties array, which respectively contain the target vSphere objects and requested properties.

For additional information on ResultSet, PropertyRequestSpec, and other features in the com.vmware.vise.data.query package, see the Java API reference included in the SDK.

Registering a Property Provider Adapter

You must register your Property Provider Adapter for the adapter to work with the Data Service. You register your Property Provider Adapter with the Data Service by using the DataServiceExtensionRegistry service. The DataServiceExtensionRegistry service contains a method named registerDataAdapter() that you must call to register your Property Provider Adapter.

A best practice for registering your adapter is to pass DataServiceExtensionRegistry as a parameter to your Property Provider Adapter class constructor, and call registerDataAdapter() from that constructor.

Example: Property Provider Adapter

The following example shows a Property Provider Adapter class. The class constructor method registers the adapter with the Data Service.

The class constructor method MyAdapter() constructs an array of property types that the adapter can supply to the Data Service in the array named providerTypes. The constructor then calls the Data Service Extension Registry method named registerDataAdapter to register the Property Provider Adapter with the Data Service. The Data Service calls the override method getProperties() when the Data Service receives a query for the kinds of properties that were specified at registration. The getProperties() method must retrieve the necessary properties, format them as a ResultSet object, and return that ResultSet. 

package com.myAdapter.PropertyProvider;
 
import com.vmware.vise.data.query;
import com.vmware.vise.data.query.PropertyProviderAdapter;
import com.vmware.vise.data.query.ResultSet;
import com.vmware.vise.data.query.type;
 
public class MyAdapter implements PropertyProviderAdapter {
 
  public MyAdapter(DataServiceExtensionRegistry extensionRegistry) {
    TypeInfo vmTypeInfo = new TypeInfo();
    vmTypeInfo.type = "VirtualMachine";
    vmTypeInfo.properties = new String[] { "myVMdata" };
    TypeInfo[] providerTypes = new TypeInfo[] {vmTypeInfo};
 
    extensionRegistry.registerDataAdapter(this, providerTypes);
  }
 
  @Override
  public ResultSet getProperties(PropertyRequestSpec propertyRequest) {
    // Logic to retrieve properties and return as result set
    ...
  }
}