AMQP Cloudlet quickstarts

The AMQP cloudlet quickstart can be used as a base for the fat-jar AMQP microservices. If you wanna create a simple backend application capable of exposing AMQP-endpoint and handling the AMQP-based communication, the AMQT cloudlet quickstart is the best way to start your development efforts.

Creating and running the AMQP cloudlet project

In order to create the AMQP cloudlet project execute the following commands:

git clone [e-mail]:rhiot/quickstarts.git
cp -r quickstarts/cloudlets/amqp amqp
cd amqp
mvn install

To start the AMQP cloudlet execute the following command:

java -jar target/rhiot-cloudlets-amqp-1.0.0-SNAPSHOT.jar

You can also build and run it as a Docker image (we love Docker and highly recommend this approach):

TARGET_IMAGE=yourUsername/rhiot-cloudlets-amqp
mvn install docker:build docker:push -Ddocker.image.target=${TARGET_IMAGE}
docker run -it ${TARGET_IMAGE}

AMQP broker

By default AMQP cloudlet quickstart starts embedded ActiveMQ AMQP broker (on 5672 port). If you would like to connect your cloudlet application to the external ActiveMQ broker (instead of starting the embedded one), run the cloudlet with the BROKER_URL environment variable or system property, for example:

java -DBROKER_URL=tcp://amqbroker.example.com:61616 -jar target/rhiot-cloudlets-amqp-1.0.0-SNAPSHOT.jar

...or...

docker run -e BROKER_URL=tcp://amqbroker.example.com:61616 -it yourUsername/rhiot-cloudlets-amqp

Sample chat application

The AMQP cloudlet quickstart is in fact a simple chat application. Clients can send the messages to the chat channel by subscribing to the broker and sending the messages to the chat AMQP queue.

The clients can subscribe to the chat updates by listening on the chat-updates AMQP topic - whenever the new message has been sent to the chat channel, the clients registered to the chat-updates will receive the updated chat history.

The quickstart also exposes the simple REST API that can be used to read the chat history using the HTTP GET request:

$ curl http://localhost:8180/chat
Hello, this is the IoT device!
I just wanted to say hello!
Hello, IoT device. Nice to meet you!

Architectural overview

When AMQP cloudlet is started with the embedded ActiveMQ broker, the architecture of the example is the following:

When you connect to the external ActiveMQ broker (using BROKER_URL option), the architecture of the example becomes more like the following diagram: