Spring Cloud with Turbine AMQP

I have previously blogged about using Spring Cloud with Turbine, a Netflix OSS library which provides a way to aggregate the information from Hystrix streams across a cluster.

The default aggregation flow is however pull-based, where Turbine requests the hystrix stream from each instance in the cluster and aggregates it together - this tends to be way more configuration heavy.

Spring Cloud Turbine AMQP offers a different model, where each application instance pushes the metrics from Hystrix commands to Turbine through a central RabbitMQ broker.

This blog post recreates the sample that I had configured previously using Spring Cloud support for AMQP - the entire sample is available at my github repo if you just want the code.

The changes are very minor for such a powerful feature, all the application which wants to feed the hystrix stream to an AMQP broker is to add these dependencies expressed in maven the following way:

<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-hystrix</artifactId>
</dependency>
<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-netflix-hystrix-stream</artifactId>
</dependency>
<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-stream-rabbit</artifactId>
</dependency>

These dependencies would now auto-configure all the connectivity details with RabbitMQ sample topic exchange and would start feeding in the hystrix stream data into this RabbitMQ topic.

Similarly on the Turbine end all that needs to be done is to specify the appropriate dependencies:

<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-turbine-stream</artifactId>
</dependency>
<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-stream-rabbit</artifactId>
</dependency>

This would consume the hystrix messages from RabbitMQ and would in turn expose an aggregated stream over an http endpoint.

Using this aggregated stream a hystrix dashboard can be displayed along these lines:

The best way to try out the sample is using docker-compose and the README with the sample explains how to build the relevant docker containers and start it up using docker-compose.