We must create a binding, which will ensure our messages get sent from our exchange to one or many queues. But what if we want to selectively send messages to different queues based on metadata found in the message? This is where exchanges come into play.Īn exchange receives messages from producers, and depending on its configuration, will send the message to one or many queues. When a producer sends directly to a queue, this message will be received by all consumers of that queue. When working with RabbitMQ, producers can send messages to a couple of different endpoints:Īs we have covered queues in the previous article, we are going to focus just on exchanges. Using a message broker allows us to build decoupling, performant applications, relying on asynchronous communication between our applications. To very briefly recap, RabbitMQ is a message broker, which handles the accepting, storing, and sending of messages between our applications.
#Masstransit .net core how to
We will cover some of the more advanced features of RabbitMQ in this article, but for an introduction, we have a great article on the topic: How to Use RabbitMQ in ASP.NET Core.Īfter finishing this article, we expect you to have a good understanding of what MassTransit is, what benefits it provides, and how we can use it in conjunction with RabbitMQ.
#Masstransit .net core code
The final syntax is still being tweaked with the goal to make it easy to test consumers, sagas, state machines (including custom state machine activities), and routing slip activities.To download the source code for this article, you can visit our GitHub repository.įor this tutorial, we recommend that you have some knowledge of RabbitMQ. As such, an initial example of a new unit test is shown below. With the container integration mentioned above, it's important to refresh how unit tests are created to simplify the creation of tests using the container. In this example, some components are registered via Autofac (the consumer dependency), and the MassTransit configuration is used to add consumers, configure the bus, etc.
![masstransit .net core masstransit .net core](https://1.bp.blogspot.com/-A2Xivk24bsg/XnjfUOydwLI/AAAAAAAAEUs/-pT0sZkb5o8FyB6tiq_Xx93Mgc_kKWplACEwYBhgL/s1600/mt003.png)
Var factory = new AutofacServiceProviderFactory() For those containers, if they support configuration via IServiceCollection and provide an IServiceProvider implementation, they can be used with MassTransit (exactly the same as if they were being used with ASP.NET Core).įor example, Autofac provides an integration package resulting in code similar to what is shown below:
![masstransit .net core masstransit .net core](https://1.bp.blogspot.com/-siS3VTNCZ4g/XYw3sa66uHI/AAAAAAAAAQg/b0e4t--evdcc8XPyqv1xCFeGryTOpPuUgCEwYBhgL/s1600/MassTransitPublishTopology.png)
Support for other containers, such as AutoFac, Simple Injector, StructureMap, and Castle Windsor will no longer be provided. MassTransit registrations (consumers, sagas, activities, futures, as well as endpoints) are now managed completely inside the container, allowing developers to create their own discovery/configuration constructs while still being able to use the AddMassTransit/UsingXxxx syntax. This means that all configuration (such as AddMassTransit, AddMediator) is built against IServiceCollection. MassTransit is now using as the standard dependency injection mechanism. For instance, all of the following options are optional, but can be configured. The hosted service can also be configured using the standard Microsoft configuration extensions. This means no more separate call to AddMassTransitHostedService and no dependency on MassTransit.AspNetCore. With v8, is now included, and the hosted service is registered by default. And without prompting, they most commonly don't see to also configure the hosted service using AddMassTransitHostedService. While the core MassTransit components can be used on their own, without a container, the vast majority of users configure MassTransit using the AddMassTransit extension method. For the most part the entire developer surface area exists within the MassTransit namespace, requiring only:
![masstransit .net core masstransit .net core](https://davidmatablog.files.wordpress.com/2021/08/2021-08-04_09h24_37.png)
![masstransit .net core masstransit .net core](https://i.stack.imgur.com/WnnjR.png)
Many new MassTransit developers struggle with missing using statements and with this change that should no longer be an issue. This makes it easier to find the right interface, extension method, or component needed. This brings the core functionality of MassTransit into a single namespace. ConsolidationĪutomatonymous, Green Pipes, and NewId have been integrated into a single MassTransit solution. Focused on the developer experience, while maintaining compatibility with previous versions, this release brings together the entire MassTransit stack. MassTransit v8 works a significant portion of the underlying components into a more manageable solution structure. MassTransit v8 will be the first major release since the availability of.