Edition 0 Updated to asp. Net core 0

Implementing a simple publish method with RabbitMQ 
The following code is a 
simplified
version of an event bus implementation for RabbitMQ, to 
showcase the whole scenario. You don’t really handle the connection this way. To see the full 
implementation, see the actual code in the 
dotnet-architecture/eShopOnContainers
 repository. 
public
class
EventBusRabbitMQ : IEventBus, IDisposable 
{ 
// Member objects and other methods ...
// ...
public
void
Publish
(IntegrationEvent @event) 
{ 
var
eventName = @event.
GetType
().
Name
; 
var
factory = 
new
ConnectionFactory
() { HostName = _connectionString }; 
using
(
var
connection = factory.
CreateConnection
()) 
using
(
var
channel = connection.
CreateModel
()) 

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140 
CHAPTER 5 | Designing and Developing Multi-Container and Microservice-Based .NET Applications 
{ 
channel.
ExchangeDeclare
(exchange: _brokerName, 
type: 
"direct"
); 
string
message = JsonConvert.
SerializeObject
(@event); 
var
body = Encoding.
UTF8
.
GetBytes
(message); 
channel.
BasicPublish
(exchange: _brokerName, 
routingKey: eventName, 
basicProperties: 
null
, 
body: body); 
} 
} 
} 
The 
actual code
 of the Publish method in the eShopOnContainers application is improved by using a 
Polly
 retry policy, which retries the task some times in case the RabbitMQ container is not ready. This 
scenario can occur when docker-compose is starting the containers; for example, the RabbitMQ 
container might start more slowly than the other containers. 
As mentioned earlier, there are many possible configurations in RabbitMQ, so this code should be 
used only for dev/test environments.