Caplin.DataSource.Publisher.IPublisher Interface Reference

An instance of IPublisher publishes messages to remote DataSource peers on behalf of an IDataProvider. It also provides access to an IMessageFactory that creates the messages to be published. More...

Inheritance diagram for Caplin.DataSource.Publisher.IPublisher:

Public Member Functions
void	PublishInitialMessage (IMessage message)
	Publishes the initial message of the data for a Subject to peers that have just requested (subscribed to) that subject. More...
void	PublishMappingMessage (IMappingMessage mapping)
	Publishes to all peers subscribed to a subject a message that instructs the remote peer to request an alternate subject in order to satisfy the subscription. More...
void	PublishSubjectErrorEvent (ISubjectErrorEvent ev)
	Publishes to all peers subscribed to a subject an event detailing an error in the subscription for that subject. Typically an IDataProvider will use this to notify the remote peers that an string they are subscribed to is no longer available. More...
void	PublishSubjectStatusEvent (ISubjectStatusEvent ev)
	Publishes to all subscribed peers an event about the change in status of a subject. More...
void	PublishToSubscribedPeers (IMessage message)
	Publishes a message to subscribed peers (that is, the peers that have already received an initial image). More...

Properties
IMessageFactory	MessageFactory [get]
	Gets the IMessageFactory used to create the messages that are published via this publisher. More...

Detailed Description

An instance of IPublisher publishes messages to remote DataSource peers on behalf of an IDataProvider. It also provides access to an IMessageFactory that creates the messages to be published.

DataSource.NET includes several implementations of IPublisher that you can use in your DataSource application: see IBroadcastPublisher, IActivePublisher. To use one of these IPublishers call the appropriate "create publisher" method of DataSource: CreateBroadcastPublisher, or CreateActivePublisher.

These three child interfaces declare no methods further to those declared in IPublisher and currently only serve to tag each IPublisher type. However, it is possible that future versions of DataSource.NET may add publisher-type specific methods to these interfaces if deemed appropriate or useful.

The following example shows an IPublisher being created by calling the Caplin.DataSource.DataSource.CreateActivePublisher method of the DataSource. An Caplin.DataSource.Namespace.INamespace is provided so that the created IPublisher knows which strings it must service.

using Caplin.DataSource;
using Caplin.DataSource.Namespace;
using Caplin.DataSource.Publisher;

namespace DataSourceExamples.Publisher
{
    public class CreateSimplePublisher
    {
        public static void CreateSimplePublisherExample(DataSource dataSource)
        {
            // Create a simple INamespace that matches subjects starting with "/FX".
            INamespace fxNamespace = new PrefixNamespace("/FX");

            // Ask the DataSource to create a publisher that uses the fxNameSpace.
            IActivePublisher publisher = dataSource.CreateActivePublisher(fxNamespace, new MyDataProvider());
        }
    }
}

Member Function Documentation

void Caplin.DataSource.Publisher.IPublisher.PublishInitialMessage

(

IMessage

message

)

Publishes the initial message of the data for a Subject to peers that have just requested (subscribed to) that subject.

Parameters

message

The message to be published.

void Caplin.DataSource.Publisher.IPublisher.PublishMappingMessage

(

IMappingMessage

mapping

)

Publishes to all peers subscribed to a subject a message that instructs the remote peer to request an alternate subject in order to satisfy the subscription.

Parameters

mapping

The IMappingMesssage to be published.

Publishing a mapping message satisfies the "initial message" requirement.

void Caplin.DataSource.Publisher.IPublisher.PublishSubjectErrorEvent

(

ISubjectErrorEvent

ev

)

Publishes to all peers subscribed to a subject an event detailing an error in the subscription for that subject. Typically an IDataProvider will use this to notify the remote peers that an string they are subscribed to is no longer available.

Parameters

ev	The ISubjectErrorEvent to be published.

void Caplin.DataSource.Publisher.IPublisher.PublishSubjectStatusEvent

(

ISubjectStatusEvent

ev

)

Publishes to all subscribed peers an event about the change in status of a subject.

Parameters

ev	The subject status event to be published.

void Caplin.DataSource.Publisher.IPublisher.PublishToSubscribedPeers

(

IMessage

message

)

Publishes a message to subscribed peers (that is, the peers that have already received an initial image).

Parameters

message

The message to be published. This may be an image or an update.

Property Documentation

IMessageFactory Caplin.DataSource.Publisher.IPublisher.MessageFactory

get

Gets the IMessageFactory used to create the messages that are published via this publisher.

The message factory.