DotNetBrightener.Plugins.EventPubSub 2023.0.21

Event Publish/Subscribe Library

© DotNet Brightener

Usage

Event message

Event message is a message that would be emitted by the IEventPublisher. The IEventHandler for the message will be proceeded sequentially, and will be stopped if the higher-prioritized handler tells the next one to stop by returning false in its HandleEvent method.

public class YourEventMessage: IEventMessage 
{
	// your model goes here
}

Non-Stopped event message

Non-stopped event message is the type of IEventMessage that will be handled by all the handlers regardless the result from the process of each handler.

public class YourEventMessage: INonStoppedEventMessage 
{
	// your model goes here
}

Define event handler

Define an event handler to process the event emitted by the IEventPublisher service as follow:

public class YourEventModelEventHandler: IEventHandler<YourEventMessage>
{
	// the higher number will tell the publisher to execute before the others
	public int Priority { get; } => 10;

	public async Task<bool> HandleEvent(YourEventMessage eventMessage) 
	{
		// do something with your eventMessage

		// if YourEventModel implements INonStoppedEventMessage, 
		// regardless the next statement, 
		// the next handler will continue to process in parallel

		// if you want to let the next handler to process the message
		return true;

		// otherwise, return false here;
		// return false;
	}
}

Emit the event

Inject IEventPublisher to your controller / service class and use it as follow:

public class SomeService 
{
	private readonly IEventPublisher _eventPublisher;
	// other services

	public SomeService(IEventPublisher eventPublisher, 
						// other services
						)
	{
		_eventPublisher = eventPublisher;
	}

	public async Task SomeMethod() 
	{
		var eventMessage = new YourEventMessage
		{
			// the event content
		};

		// if you want to let the event message to be processed in the current thread
		await _eventPublisher.Publish(eventMessage);

		// if you want to let the event message to be processed in the another thread
		await _eventPublisher.Publish(eventMessage, true);
	}
}

Register at startup

You will need to install the package DotNetBrightener.Plugins.EventPubSub.DependencyInjection from nuget.org and follow instruction there.