Apama 10.7.2 | Connecting Apama Applications to External Components | Standard Connectivity Plug-ins | The Digital Event Services Transport Connectivity Plug-in | About the Digital Event Services transport
 
About the Digital Event Services transport
Software AG Digital Event Services is a messaging system for communicating between different Software AG products using events. Digital Event Services allows event definitions to be converted between a product's internal event or document definition to digital event types and vice versa, so participating products can share a set of event definitions. When you develop Apama applications that make use of Digital Event Services, the translation between digital event type definitions and Apama event types is done automatically. When digital events are sent to or received from Digital Event Services, they are converted to or from Apama events.
For details of the event mapping, see the .mon source file that is generated into the autogenerated node of your Apama project in Software AG Designer. Note that digital event types that contain nested events (or sequences of nested events) are converted to Apama event definitions that have an optional member (or sequence of optionals) for that event type. See the description of the optional type in the API Reference for EPL (ApamaDoc) for more information. When digital events are converted to Apama events, fields of other types with no value set are set to the default value for that type (see also Default values for types).
To use digital event types in your Apama application, proceed as follows:
1. Use Software AG Installer to install Digital Event Services. See Installing Software AG Products for more information.
2. Configure Digital Event Services as described in Using Digital Event Services to Communicate between Software AG Products. This guide also explains how to use SSL with Digital Event Services.
3. Use Software AG Designer to add the Digital Event Services connectivity bundle to your Apama project. For detailed information, see Using the Digital Event Services connectivity bundle.
Note:
In addition to using Software AG Designer to add bundles, you can also do this using the apama_project command-line tool. See Creating and managing an Apama project from the command line for more information.
4. Use the Digital Event Types editor to turn digital event types into Apama event types and existing Apama event types into digital event types. Apama event types that correspond to digital event types can be used just like ordinary Apama events. You can create digital events, create event expressions for them, set and get their contents, pass them around internally between monitors and contexts, and much more. See the above-mentioned topic for more information.
5. This transport provides a dynamic chain manager which creates chains automatically when EPL subscribes or sends to a correlator channel with a name corresponding to the .CHANNEL constant on a Digital Event Services event. For this transport, there is no need to customize the chain configuration in the YAML configuration file in any way.
For more information on YAML configuration files, see Using Connectivity Plug-ins and especially Configuration file for connectivity plug-ins.
6. Edit the DigitalEventServices.properties file to configure the Digital Event Services connectivity plug-in which defines the Apama connection to Digital Event Services. See the above-mentioned topic for more information.