KubeEdge Counter Demo

Description

Counter is a pseudo device that user can run this demo without any extra physical devices.

Counter run at edge side, and user can control it in web from cloud side, also can get counter value in web from cloud side.

Prerequisites

Hardware Prerequisites

• RaspBerry PI (RaspBerry PI 4 has been used for this demo).

Software Prerequisites

• A running Kubernetes cluster.

  NOTE:

  add follows --insecure-port=8080 and --insecure-bind-address=0.0.0.0 options into /etc/kubernetes/manifests/kube-apiserver.yaml

• KubeEdge v1.5+

• MQTT Broker is running on Raspi.

Steps to run the demo

Create the device model and device instance for the counter

With the Device CRD APIs now installed in the cluster, we create the device model and instance for the counter using the yaml files.

$ cd $GOPATH/src/github.com/kubeedge/examples/kubeedge-counter-demo
# replace "<your edge node name>" with your edge node name
$ sed -i "s#edge-node#<your edge node name>#" crds/kubeedge-counter-instance.yaml
$ kubectl create -f crds/kubeedge-counter-model.yaml
$ kubectl create -f crds/kubeedge-counter-instance.yaml

Run KubeEdge Web App

The KubeEdge Web App runs in a VM on cloud.

$ cd $GOPATH/src/github.com/kubeedge/examples/kubeedge-counter-demo/web-controller-app
$ make
$ make docker
$ cd $GOPATH/src/github.com/kubeedge/examples/kubeedge-counter-demo/crds
$ kubectl create -f kubeedge-web-controller-app.yaml

Note: instance must be created after model and deleted before model.

Run KubeEdge Pi Counter App

The KubeEdge Counter App run in raspi.

$ cd $GOPATH/src/github.com/kubeedge/examples/kubeedge-counter-demo/counter-mapper
$ make
$ make docker
$ cd $GOPATH/src/github.com/kubeedge/examples/kubeedge-counter-demo/crds
$ kubectl create -f kubeedge-pi-counter-app.yaml

The App will subscribe to the $hw/events/device/counter/twin/update/document topic, and when it receives the expected control command on the topic, it will turn on/off the counter, also it will fresh counter value and publish value to $hw/events/device/counter/twin/update topic, then the latest counter status will be sychronized between edge and cloud.

At last, user can get the counter status at cloud side.

Control counter by visiting Web App Page

• Visit web app page by the web app link MASTER_NODE_IP:80.

  

• Choose ON option, and click Execute, then user can see counter start to count by docker logs -f counter-container-id at edge side.

• Choose STATUS option, then click Execute to get the counter status, finally counter status and current counter value will display in web.

  also you can watch counter status by kubectl get device counter -o yaml -w at cloud side.

• Choose OFF option, and click Execute, counter stop work at edge side.