SOA Web Services - Direct Connection Runtime Pattern

Direct Connection Runtime Pattern

The Direct Connection pattern is depicted in the following figure.

In this pattern, a source application connects directly to a target application using a connector. The connector itself may be explicitly or implicitly modeled. Depending on the connector and interaction variation, the connector may be classified as follows:

• Adapter Connector
• Path Connector
• Message Connector
• Call Connector
• Call Adapter Connector

The Adapter and Path connectors are explained previously. The connector is called a message connector whenever we use messaging services for connection. The Call Connector indicates a direct call to the service, while a Call Adapter Connector indicates a call through an adapter.

The source and target applications are modeled using the Application Server/ Services node. The Rules Repository and Domain QoS Providers are optional and need not be shown in the pattern artefact. As discussed earlier, the Rules Repository contains the rules for connection. The QoS Provider defines the various Quality-of- Service attributes for the connection.

In SOA, a rules repository may be implemented as a service registry.

This pattern provides a direct connection between a service consumer and a service provider with the help of connectors. The pattern is classified into the following categories depending on the connector used:

• Single Adapter connector
• Coupling Adapter connector
• Service Bus

Each of these is discussed further.