Integrating with other systems

Often people want to consume messages off of their broker that are coming from other non-MassTransit systems. The below video reviews how to do this.

Key Points

You must specifically configure the receive endpoint

Exclude this endpoint from the topology mapping. Since this endpoint is defined by a different system, we don't need MassTransit's help here.

endpointConfigurator.ConfigureConsumeTopology = false;

Add the RawJsonSerializer to the list of serializers supported. The serializer specifically looks for application/json versus the standard content-type used by MassTransit which is application/vnd.masstransit+json.


If you want to have MT bind the endpoint to the correct topic you can do the following:

if(endpointConfigurator is IRabbitMqReceiveEndpointConfigurator rabbit) 

If the existing system isn't setting the content type

If the messages doesn't have a content-type set, you can tell MassTransit what the default content type should be. Since, as the app developer, you know the content is application/json you can set that manually. Then when a message comes in without a header, MT will select the correct one.

endpointConfigurator.DefaultContentType = new ContentType("application/json");