问题
I've tried using MassTransit to publish a message to a topic named events
in an Azure Service Bus. I have problem configuring MassTransit to use my predefined topic events
, instead it creates a new topic named by the namespace/classname for the message type. So I wonder how to specify which topic to use instead of creating a new one.
This is the code I've tested with:
using System;
using System.Threading.Tasks;
using MassTransit;
using MassTransit.AzureServiceBusTransport;
using Microsoft.ServiceBus;
namespace PublisherNameSpace
{
public class Publisher
{
public static async Task PublishMessage()
{
var topic = "events";
var bus = Bus.Factory.CreateUsingAzureServiceBus(
cfg =>
{
var azureServiceBusHost = cfg.Host(new Uri("sb://<busname>.servicebus.windows.net"), host =>
{
host.OperationTimeout = TimeSpan.FromSeconds(5);
host.TokenProvider =
TokenProvider.CreateSharedAccessSignatureTokenProvider(
"RootManageSharedAccessKey",
"<key>"
);
});
cfg.ReceiveEndpoint(azureServiceBusHost, topic, e =>
{
e.Consumer<TestConsumer>();
});
});
await bus.Publish<TestConsumer>(new TestMessage { TestString = "testing" });
}
}
public class TestConsumer : IConsumer<TestMessage>
{
public Task Consume(ConsumeContext<TestMessage> context)
{
return Console.Out.WriteAsync("Consuming message");
}
}
public class TestMessage
{
public string TestString { get; set; }
}
}
回答1:
If you want to consume from a specific topic, create a subscription endpoint instead of a receive endpoint, and specify the topic and subscription name in the configuration.
The simplest form is shown in the unit tests:
https://github.com/MassTransit/MassTransit/blob/develop/src/MassTransit.Azure.ServiceBus.Core.Tests/Subscription_Specs.cs
回答2:
The accepted answer clears up the subscription side:
cfg.SubscriptionEndpoint(
host,
"sub-1",
"my-topic-1",
e =>
{
e.ConfigureConsumer<TestConsumer>(provider);
});
For those wondering how to get the bus configuration right on the publish side, it should look like:
cfg.Message<TestMessage>(x =>
{
x.SetEntityName("my-topic-1");
});
You can then call publish on the bus:
await bus.Publish<TestMessage>(message);
Thanks to @ChrisPatterson for pointing this out to me!
来源:https://stackoverflow.com/questions/49434228/how-to-specify-which-azure-service-bus-topic-to-use-with-masstransit