Edition 0 Updated to asp. Net core 0

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ConnectionString=basketdata 
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EventBusConnection=rabbitmq 
As mentioned before, the name of the microservice 
basketdata
is resolved by Docker’s internal 
network DNS. 
Implementing event-based communication between 
microservices (integration events) 
As described earlier, when you use event-based communication, a microservice publishes an event 
when something notable happens, such as when it updates a business entity. Other microservices 
subscribe to those events. When a microservice receives an event, it can update its own business 
entities, which might lead to more events being published. This is the essence of the eventual 
consistency concept. This publish/subscribe system is usually performed by using an implementation 
of an event bus. The event bus can be designed as an interface with the API needed to subscribe and 
unsubscribe to events and to publish events. It can also have one or more implementations based on 
any inter-process or messaging communication, such as a messaging queue or a service bus that 
supports asynchronous communication and a publish/subscribe model. 
You can use events to implement business transactions that span multiple services, which give you 
eventual consistency between those services. An eventually consistent transaction consists of a series 

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CHAPTER 5 | Designing and Developing Multi-Container and Microservice-Based .NET Applications 
of distributed actions. At each action, the microservice updates a business entity and publishes an 
event that triggers the next action. Figure 6-18 below, shows a PriceUpdated event published through 
an event bus, so the price update is propagated to the Basket and other microservices. 
Figure 6-18. Event-driven communication based on an event bus 
This section describes how you can implement this type of communication with .NET by using a 
generic event bus interface, as shown in Figure 6-18. There are multiple potential implementations, 
each using a different technology or infrastructure such as RabbitMQ, Azure Service Bus, or any other 
third-party open-source or commercial service bus.