[Book] GitOps Cookbook: 04. Helm

// scaffold the project
$ helm create <name>

https://github.com/gitops-cookbook/helm-charts/tree/master/pacman

$ helm template .

// override
$ helm template --set replicaCount=3 .

$ helm install pacman .

$ kubectl get pods

$ helm history pacman

$ helm uninstall pacman

5.3 Updating a Container Image in Helm

values.yaml - update the version
Chart.yaml - update the appVersion field

$ helm upgrade pacman .

$ helm history pacman

$ helm rollback pacman 1

$ helm template pacman -f newvalues.yaml .

5.4 Packaging and Distributing a Helm Chart

$ helm package .

$ helm package --sign --key '[email protected]' \
--keyring /home/me/.gnupg/secring.gpg .

$ helm verify pacman-0.1.0.tgz

[OK!] 5.5 Deploying a Chart from a Repository

Делаю:
26.05.2023

$ helm repo add bitnami https://charts.bitnami.com/bitnami

$ helm repo update
$ helm repo list
$ helm search repo postgresql

$ helm install my-db \
  bitnami/postgresql \
  --namespace postgres \
  --create-namespace \
  --set auth.username=user1,auth.password=postgres1,auth.database=postgresdb1,primary.persistence.enabled=false

// To get the password for "user1" run:
$ {
  export POSTGRES_PASSWORD=$(kubectl get secret --namespace postgres my-db-postgresql -o jsonpath="{.data.password}" | base64 -d)
  echo ${POSTGRES_PASSWORD}
}

// To connect to your database
$ kubectl run my-db-postgresql-client --rm --tty -i --restart='Never' --namespace postgres --image docker.io/bitnami/postgresql:15.3.0-debian-11-r4 --env="PGPASSWORD=$POSTGRES_PASSWORD" \
      --command -- psql --host my-db-postgresql -U user1 -d postgresdb1 -p 5432

// To connect to your database from outside the cluster
$ kubectl port-forward --namespace postgres svc/my-db-postgresql 5432:5432 &
    PGPASSWORD="$POSTGRES_PASSWORD" psql --host 127.0.0.1 -U user1 -d postgresdb1 -p 5432

$ kubectl get pods -n postgres
$ kubectl get statefulset -n postgres

$ helm show values bitnami/postgresql

[OK!] 5.6 Deploying a Chart with a Dependency

Делаю:
26.05.2023

https://github.com/bitnami/charts/tree/main/bitnami/postgresql/#installing-the-chart

$ cd ~/tmp
$ mkdir -p music/templates
$ cd music

$ cat > templates/deployment.yaml << EOF
apiVersion: apps/v1
kind: Deployment
metadata:
  name: 
  labels:
    app.kubernetes.io/name: 
    app.kubernetes.io/version: 
spec:
  replicas: 
  selector:
    matchLabels:
      app.kubernetes.io/name: 
  template:
    metadata:
      labels:
        app.kubernetes.io/name: 
    spec:
      containers:
          - image: ":"
            imagePullPolicy: 
            securityContext:
            name: 
            ports:
              - containerPort: 
                name: http
                protocol: TCP
            env:
              - name: QUARKUS_DATASOURCE_JDBC_URL
                value: 
              - name: QUARKUS_DATASOURCE_USERNAME
                value: 
              - name: QUARKUS_DATASOURCE_PASSWORD
                valueFrom:
                  secretKeyRef:
                    name: 
                    key: 
EOF

$ cat > templates/service.yaml << EOF
apiVersion: v1
kind: Service
metadata:
  labels:
    app.kubernetes.io/name: 
  name: 
spec:
  ports:
    - name: http
      port: 
      targetPort: 
  selector:
    app.kubernetes.io/name: 
EOF

$ cat > Chart.yaml << EOF
apiVersion: v2
name: music
description: A Helm chart for Music service

type: application
version: 0.1.0
appVersion: "1.0.0"

dependencies:
  - name: postgresql
    repository: "https://charts.bitnami.com/bitnami"
    version: 12.5.5
EOF

$ cat > values.yaml << EOF
image:
  repository: quay.io/gitops-cookbook/music
  tag: "1.0.0"
  pullPolicy: Always
  containerPort: 8080

replicaCount: 1

postgresql:
  server: jdbc:postgresql://music-db-postgresql:5432/postgresdb1
  postgresqlUsername: user1
  secretName: music-db-postgresql
  secretKey: password
EOF

$ helm dependency update

.
├── Chart.lock
├── charts
│   └── postgresql-12.5.5.tgz
├── Chart.yaml
├── templates
│   ├── deployment.yaml
│   └── service.yaml
└── values.yaml

2 directories, 6 files

$ helm install music-db \
  --namespace music \
  --create-namespace \
  --set global.postgresql.auth.username=user1,global.postgresql.auth.password=postgres1,global.postgresql.auth.database=postgresdb1,primary.persistence.enabled=false .

$ kubectl get pods -n music
NAME                      READY   STATUS      RESTARTS       AGE
music-6d957c46bf-5w2g8    1/1     Running     2 (4m3s ago)   4m12s
music-db-postgresql-0     1/1     Running     0              4m12s

// GET ADMIN_POSTGRES_PASSWORD
$ {
  export ADMIN_POSTGRES_PASSWORD=$(kubectl get -n music secret music-db-postgresql -o jsonpath="{.data.postgres-password}" | base64 -d)
  echo ${POSTGRES_PASSWORD}
}

// To connect to your database as admin
$ kubectl run my-db-postgresql-client --rm --tty -i --restart='Never' --namespace music --image docker.io/bitnami/postgresql:15.3.0-debian-11-r4 --env="PGPASSWORD=$ADMIN_POSTGRES_PASSWORD" \
      --command -- psql --host music-db-postgresql -U postgres -d postgres -p 5432

// GET USER POSTGRES_PASSWORD
$ {
  export USER_POSTGRES_PASSWORD=$(kubectl get -n music secret music-db-postgresql -o jsonpath="{.data.password}" | base64 -d)
  echo ${POSTGRES_PASSWORD}
}

// To connect to your database as user1
$ kubectl run my-db-postgresql-client --rm --tty -i --restart='Never' --namespace music --image docker.io/bitnami/postgresql:15.3.0-debian-11-r4 --env="PGPASSWORD=$USER_POSTGRES_PASSWORD" \
      --command -- psql --host music-db-postgresql -U user1 -d postgresdb1 -p 5432

// To connect to your database from outside the cluster
$ kubectl port-forward --namespace music svc/music-db-postgresql 5432:5432 &
    PGPASSWORD="$USER_POSTGRES_PASSWORD" psql --host 127.0.0.1 -U user1 -d postgresdb1 -p 5432

$ kubectl get services -n music
NAME                     TYPE        CLUSTER-IP       EXTERNAL-IP   PORT(S)    AGE
music                    ClusterIP   10.109.139.154   <none>        8080/TCP   83s
music-db-postgresql      ClusterIP   10.106.198.189   <none>        5432/TCP   83s
music-db-postgresql-hl   ClusterIP   None             <none>        5432/TCP   83s

$ kubectl port-forward -n music service/music 8080:8080

$ curl localhost:8080/song | jq
[
  {
    "id": 1,
    "artist": "DT",
    "name": "Quiero Munchies"
  },
  {
    "id": 2,
    "artist": "Lin-Manuel Miranda",
    "name": "We Don't Talk About Bruno"
  },
  {
    "id": 3,
    "artist": "Imagination",
    "name": "Just An Illusion"
  },
  {
    "id": 4,
    "artist": "Txarango",
    "name": "Tanca Els Ulls"
  },
  {
    "id": 5,
    "artist": "Halsey",
    "name": "Could Have Been Me"
  }
]

[OK!] 5.7 Triggering a Rolling Update Automatically

Делаю:
27.05.2023

$ cd ~/tmp
$ mkdir -p greetings/templates
$ cd greetings

$ cat > templates/deployment.yaml << EOF
apiVersion: apps/v1
kind: Deployment
metadata:
  name: 
  labels:
    app.kubernetes.io/name: 
    app.kubernetes.io/version: 
spec:
  replicas: 
  selector:
    matchLabels:
      app.kubernetes.io/name: 
  template:
    metadata:
      labels:
        app.kubernetes.io/name: 
    spec:
      containers:
          - image: ":"
            imagePullPolicy: 
            securityContext:
            name: 
            ports:
              - containerPort: 
                name: http
                protocol: TCP
            env:
              - name: GREETING
                valueFrom:
                  configMapKeyRef:
                    name: 
                    key: greeting
EOF

$ cat > templates/service.yaml << EOF
apiVersion: v1
kind: Service
metadata:
  labels:
    app.kubernetes.io/name: 
  name: 
spec:
  ports:
    - name: http
      port: 
      targetPort: 
  selector:
    app.kubernetes.io/name: 
EOF

$ cat > templates/configmap.yaml << EOF
apiVersion: v1
kind: ConfigMap
metadata:
  name: greeting-config
data:
  greeting: Aloha
EOF

$ cat > Chart.yaml << EOF
apiVersion: v2
name: greetings
description: A Helm chart for Greetings service

type: application
version: 0.1.0
appVersion: "1.0.0"
EOF

$ cat > values.yaml << EOF
image:
  repository: quay.io/gitops-cookbook/greetings
  tag: "1.0.0"
  pullPolicy: Always
  containerPort: 8080

replicaCount: 1

configmap:
  name: greeting-config
EOF

$ helm install greetings .

$ kubectl get pods
NAME                         READY   STATUS    RESTARTS   AGE
greetings-6df4d99d46-vzrj9   1/1     Running   0          29s

$ kubectl port-forward service/greetings 8080:8080

$ curl localhost:8080

returns

Aloha Ada

Update the ConfigMap

$ cat > templates/configmap.yaml << EOF
apiVersion: v1
kind: ConfigMap
metadata:
  name: greeting-config
data:
  greeting: Hola
EOF

$ helm upgrade greetings .

$ kubectl port-forward service/greetings 8080:8080

$ curl localhost:8080

returns

Aloha Alexandra⏎

There are no changes in the Deployment object, there is no restart of the pod;

$ cat > templates/deployment.yaml << EOF
apiVersion: apps/v1
kind: Deployment
metadata:
  name: 
  labels:
    app.kubernetes.io/name: 
    app.kubernetes.io/version: 
spec:
  replicas: 
  selector:
    matchLabels:
      app.kubernetes.io/name: 
  template:
    metadata:
      labels:
        app.kubernetes.io/name: 
      annotations:
        checksum/config: 
    spec:
      containers:
          - image: ":"
            imagePullPolicy: 
            securityContext:
            name: 
            ports:
              - containerPort: 
                name: http
                protocol: TCP
            env:
              - name: GREETING
                valueFrom:
                  configMapKeyRef:
                    name: 
                    key: greeting
EOF

$ cat > templates/configmap.yaml << EOF
apiVersion: v1
kind: ConfigMap
metadata:
  name: greeting-config
data:
  greeting: Namaste
EOF

$ helm upgrade greetings .

$ kubectl port-forward service/greetings 8080:8080

$ curl localhost:8080

returns

Namaste Ada⏎

$ kubectl describe pod greetings-bd8c9c4df-59xrj

***
Annotations:      checksum/config:
***

$ cat > templates/configmap.yaml << EOF
apiVersion: v1
kind: ConfigMap
metadata:
  name: greeting-config
data:
  greeting: Привет!
EOF

$ helm upgrade greetings .

$ kubectl port-forward service/greetings 8080:8080

// Нужно подождать перестартовки пода
$ curl localhost:8080

Привет! Ada⏎