Kubernetes introduction presentation

Repository contains simple Java application. Application serve /books endpoint with list of books read from file. File name is passed via BOOKS_FILE_PATH environment variable. Default (8080) port is used.

Build application
```
mvn package
```

Run application

java -jar target/kubernetes-demo-0.0.1.jar

Prepare env

Assumption

Windows 8
cygwin
python 2.7
VirtualBox

Install minikube

Install kubectl

Configure kubectl completion

Link: cheatsheet

source <(kubectl completion bash)
echo "source <(kubectl completion bash)" >> ~/.bashrc

Install docker

Get binary

wget https://download.docker.com/win/static/stable/x86_64/docker-17.09.0-ce.zip

Unzip file
```
unzip docker-17.09.0-ce.zip
```
Add docker cli to PATH env
```
export PATH="$(pwd)/docker:${PATH}"
```
Test if docker cli is in PATH
```
type docker
```

Connect docker cmd to minikube

Export docker env
```
eval $(minikube docker-env)
```
Test docker
```
docker ps
```

Configure gcloud cli

Run in windows CMD or cygwin

gcloud init
gcloud auth login
gcloud projects list
gcloud config set project kubernetes-test-252820
gcloud config set compute/zone europe-west6-c

Fix kube config in cygwin

sed -i "s/cmd-path:.*/cmd-path: gcloud/" ~/.kube/config

Run in windows CMD with Admin rights

gcloud components update
gcloud components install docker-credential-gcr

Create kubernetes cluster

gcloud container clusters create jdd

Delete cluster

gcloud container clusters delete jdd

gcloud services enable containerregistry.googleapis.com

DO NOT USE: gcloud auth configure-docker docker-credential-gcr configure-docker

gcloud init gcloud auth login --no-launch-browser gcloud config set project kubernetes-test-252820 gcloud config set compute/zone europe-west6-c

Create simple REST app

Go to Spring initializer page: start.spring.io
1. Select components
  1. web
  2. actuator
Download generated project
Open generated project in the IDE

Add lombok dependency

<dependency>
    <groupId>org.projectlombok</groupId>
    <artifactId>lombok</artifactId>
    <optional>true</optional>
</dependency>

Enable "Annotation processing"
Create controller @RestController @GetMapping("/")
DEMO
Install Docker plugin
Install Markdown plugin
Install Lombok plugin

Connect IntelliJ Docker plugin to minikube . Get minikube env

minikube docker-env|sed "s/tcp:/https:/"

Set "TCP Socket"
1. "Engine API URL" set to DOCKER_HOST
2. "Certificates folder" set to DOCKER_CERT_PATH

Build docker directly on the minikube VM . Copy Dockerfile and jar

scp -i $(minikube ssh-key) -r . docker@$(minikube ip):.

Build docker directly on minikube VM

minikube ssh
docker build . --tag demo:0.0.1
docker run --name demo -d -p 8080:8080 -e "BOOKS_FILE_PATH=/books/books.json" -v $(pwd):/books demo:0.0.1
curl http://localhost:8080/books

Remove docker instance

docker rm -f demo

Minikube commands

minikube delete
minikube start
minikube ip
minikube ssh
minikube kubectl
minikube addons list

kubectl label namespace NAMESPACE istio-injection=enabled kubectl scale deployment demo --replicas 5

export INGRESS_HOST=$(kubectl -n istio-system get service istio-ingressgateway -o jsonpath='{.status.loadBalancer.ingress[0].ip}') export INGRESS_PORT=$(kubectl -n istio-system get service istio-ingressgateway -o jsonpath='{.spec.ports[?(@.name=="http2")].port}') export SECURE_INGRESS_PORT=$(kubectl -n istio-system get service istio-ingressgateway -o jsonpath='{.spec.ports[?(@.name=="https")].port}')

Istio

Run in windows CMD with Admin rights

gcloud components install beta

Create kubernetes cluster with istio enabled

gcloud beta container clusters create jdd-istio2 \
    --addons=Istio --istio-config=auth=MTLS_PERMISSIVE \
    --machine-type=n1-standard-2 \
    --num-nodes=4

In case when kubectl is not configured

gcloud container clusters get-credentials jdd

kubectl create clusterrolebinding "cluster-admin-$(whoiam)" --clusterrole=cluster-admin --user="$(gcloud config get-value core/account)"

kubectl apply -f "https://cloud.weave.works/k8s/scope.yaml?k8s-version=$(kubectl version | base64 | tr -d '\n')"