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Developer Example: Dev tools -- The Event Service

The AG Toolkit infrastructure contains tools that can be used in different ways other than the default. One useful component of the AG infrastructure is group network messaging. This can be reused by other applications if desired. The primary method of sending event-like messages over the network is through the Event Service and Event Client. An event service is usually run within a VenueServer. Using the standard event service in this way helps us to more easily connect our applications through firewalls. Another option for applications is to start a separate dedicated event service. While this loses the advantage of easily connecting to the VenueServer's event service without firewall modifications, it may be worthwhile for some shared applications that use entirely separate event service to optimize performance. Examples standaloneEvent/simple Server.py Client.py A simple event service and client. Start an event service:

eventService = EventService(name="test", description="atest", id="testId", type="event", location=('localhost',7002)) eventService.CreateChannel("Test") eventService.Start()

If desired, start a local event client that can receive and send events:

vec = InProcessVenueEventClient(eventService, privateId, channel) vec.Start()

Client: A simple client

vec = SecureVenueEventClient(location, privateId, channel) vec.Start()

The standard AG event service sends all messages to all users. This is generally useful in the AG, but is not mandatory. The event service can and has been modified to do more complex management of messages. While the Access Grid event service is often used in a single mode, much of the toolkit can be customized to address different needs such as performance critical applications.

 

Examples

Web-based visualization

The AG event service was used to build a bridge between a rendering cluster and a user interacting with a remote client the displayed the rendered frames. This worked by... (fill in details)

AttachmentSize
standaloneEvent2008.zip1.92 KB

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