Connector Provider¶

The purpose of the connector provider is to provide information on how to configure, and initialize a particular connector implementation. It is both an information component describing the properties of the connector during set up, and also the factory class used to create an instance of the connector at runtime.

The ConnectorProvider interface¶

All connector providers implement the ConnectorProvider interface. This interface includes the getConnectorType() method that returns the ConnectorType that is added to a Connection object used to create an instance of the connector.

The connection object contains properties needed by the connection object to operate. It includes a connector type object that is used when constructing the connector and an endpoint object that defines where the corresponding digital resource is located.

The connector type describes the capabilities of the connector such as:

• the java class of this connector provider. A connector provider is the factory for its Connector. It is typically called from the Connector Broker. The connector broker uses the connectorProviderClassName in the connector type to create an instance of the connector provider.

• the configurationProperties that can be added to the connector's connection object to adapt its behavior. The administrator who is configuring the connector used the recognizedConfigurationProperties from the connector type to determine the properties

The ConnectorProvider interface also defines the getConnector() method called to construct an instance of the connector at runtime using the connection object.

Audit Logging¶

If the connector provider implements the AuditLoggingComponent interface, it is passed an audit log object used to create child audit log objects that are passed to each connector instance when it is created.

The connector provider is also able to return the ComponentDescription object used in each child audit log.

ConnectorProviderBase class¶

Egeria provides a base class for the connector provider called ConnectorProviderBase that implements the factory classes for a connector. It also stores all the properties needed by the information methods such as getConnectorType(). Most connector provider implementations use this base class and only need to pass appropriate values to initialize the properties for the information methods.

Writing the Connector Provider¶

Each connector provider implements the following interface:

org.odpi.openmetadata.frameworks.connectors.ConnectorProvider

There is a base class that provides much of the implementation for a connector provider.

org.odpi.openmetadata.frameworks.connectors.ConnectorProviderBase

This assumes:

• There is a single connector implementation class for the connector.
• The connector is instantiated with the default constructor. This means all of its configuration information is contained in the Connection object supplied on the initialize() method.

If your connector implementation matches these requirements, its connector provider implementation need only implement a constructor to configure the base class's function with details of itself and the Java class of the connector it needs using:

• a GUID for the connector type
• a name for the connector type.
• a description of what the connector is for and how to configure it.
• the connector class it instantiates.
• a list of the additional properties, configuration properties and secured properties needed to configure instances of the connector.
• a description of the connector for its audit log (if the connector implements AuditLoggingComponent).

/**
 * XXXStoreProvider is the OCF connector provider for the XXX connector.
 */
public class XXXStoreProvider extends ConnectorProviderBase
{
    /*
     * Unique identifier of the connector for the audit log.
     */
    private static final int    connectorComponentId   = 10001; /* Add unique number here */

    /*
     * Unique identifier for the connector type.
     */
    private static final String connectorTypeGUID      = "Add unique GUID here";

    /*
     * Descriptive information about the connector for the connector type and audit log.
     */
    private static final String connectorQualifiedName = "MyOrg:XXXStoreConnector";
    private static final String connectorDisplayName   = "XXX Store Connector";
    private static final String connectorDescription   = "Connector supports ... add details here.";
    private static final String connectorWikiPage      = "Add url to documentation here";


    /*
     * Define the name of the connector implementation.
     */
    private static final String connectorClassName = "packagename.XXXStoreConnector";

    /*
     * Define the name of configuration properties.
     */
    public static final String TEMPLATE_QUALIFIED_NAME_CONFIGURATION_PROPERTY = "templateQualifiedName";

    /**
     * Constructor used to initialize the ConnectorProviderBase class.
     */
    public XXXStoreProvider()
    {
        super();

        /*
         * Set up the class name of the connector that this provider creates.
         */
        super.setConnectorClassName(connectorClassName);

        /*
         * Set up the connector type that should be included in a connection used to configure this connector.
         */
        ConnectorType connectorType = new ConnectorType();
        connectorType.setType(ConnectorType.getConnectorTypeType());
        connectorType.setGUID(connectorTypeGUID);
        connectorType.setQualifiedName(connectorQualifiedName);
        connectorType.setDisplayName(connectorDisplayName);
        connectorType.setDescription(connectorDescription);
        connectorType.setConnectorProviderClassName(this.getClass().getName());

        List<String> recognizedConfigurationProperties = new ArrayList<>();
        recognizedConfigurationProperties.add(TEMPLATE_QUALIFIED_NAME_CONFIGURATION_PROPERTY);
        connectorType.setRecognizedConfigurationProperties(recognizedConfigurationProperties);

        super.connectorTypeBean = connectorType;

        /*
         * Set up the component description used in the connector's audit log messages.
         */
        AuditLogReportingComponent componentDescription = new AuditLogReportingComponent();

        componentDescription.setComponentId(connectorComponentId);
        componentDescription.setComponentName(connectorQualifiedName);
        componentDescription.setComponentDescription(connectorDescription);
        componentDescription.setComponentWikiURL(connectorWikiPage);

        super.setConnectorComponentDescription(componentDescription);
    }
}

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