Jenkins: Redis deployment, and Helm subchart values

By | 11/01/2020
 

The task is to create a Jenkins job to deploy Redis to Dev/Stage/Prod Kubernetes clusters.

In the Redis: running Master-Slave replication in Kubernetes we did it manually to see how it’s working, now it’s time to automate it.

The main question is how to pass parameters for different environments during the deployment? I’d like to use an existing chart for Bitnami, and at the same time to deploy it from our own Helm chart with a values.yaml file fie each of the Dev/Stage/Prod environments.

Well, we still can create our Helm chart and add the Redis Bitnami chart as a Helm dependency, and pass a values.yaml from the parent chart.

The documentation is here>>>.

So, what we will do:

  • the parent chart – backend-redis
    • with the bitnami/redis dependency
    • with the env directory
      • with the devcatalog
        • with the values.yaml file inside
  • and in Jenkins, it will be deployed as helm install backend-redis -f env/${ENV}/values.yaml

Let’s go.

Creating parent Helm chart

In a repository with our services create a new chart:

helm create backend-redis
Creating backend-redis

Remove all template files – we don’t need them here:

rm -rf backend-redis/templates/*

Create directories for the values.yaml:

mkdir -p backend-redis/env/{dev,stage,prod}

Copy a config from the previous post (Rus):

cp ~/Temp/redis-opts.yaml backend-redis/env/dev/values.yaml

Check its content:

head backend-redis/env/dev/values.yaml
global:
redis:
password: "blablacar"
metrics:
enabled: true
serviceMonitor:
enabled: true
namespace: "monitoring"

Okay, just need to delete the password from here as it will be passed from a Jenkins Password parameter with the helm install --set during deployment.

Helm: a values.yaml for a subchart

Also, what do we need to change here is to add a child subchart’s name at the very beginning so we can use it with the parent’s chart and Helm will apply those values to the Redis chart from Bitnami which is our child chart.

Add the redis word to the beginning of the file and remove the password‘s value:

redis:
  global:
    redis:
      password: ""

  metrics:
    enabled: true
    serviceMonitor:
      enabled: true
      namespace: "monitoring"

  master:
    persistence:
      enabled: false
    service:
      type: LoadBalancer
      annotations:
        service.beta.kubernetes.io/aws-load-balancer-internal: "true"
...

Now, we can add a dependency to our parent backend-redis chart, add the Redis chart:

helm search repo redis
NAME                                    CHART VERSION   APP VERSION     DESCRIPTION
bitnami/redis                           11.2.3          6.0.9           Open source, advanced key-value store. It is of...
bitnami/redis-cluster                   3.2.10          6.0.9           Open source, advanced key-value store. It is of...
stable/prometheus-redis-exporter        3.5.1           1.3.4           DEPRECATED Prometheus exporter for Redis metrics
stable/redis                            10.5.7          5.0.7           DEPRECATED Open source, advanced key-value stor...
stable/redis-ha                         4.4.4           5.0.6           Highly available Kubernetes implementation of R...
stable/sensu                            0.2.3           0.28            Sensu monitoring framework backed by the Redis ...

Let’s use the bitnami/redis 11.2.3, add dependencies to the Chart.yaml of the parent’s chart:

...
dependencies:
- name: redis
  version: ~11.2
  repository: "@bitnami"

Add the repository:

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

Run for the test:

helm install backend-redis . --dry-run -f env/dev/values.yaml --debug
install.go:172: [debug] Original chart version: ""
install.go:189: [debug] CHART PATH: /home/setevoy/Work/devops-kubernetes/projects/backend/services/backend-redis
Error: found in Chart.yaml, but missing in charts/ directory: redis
helm.go:94: [debug] found in Chart.yaml, but missing in charts/ directory: redis
...

Error: found in Chart.yaml, but missing in charts/ directory: redis” – ah, yeah, forgot. Update dependencies:

helm dependency update
Hang tight while we grab the latest from your chart repositories...
...Successfully got an update from the "equinor-charts" chart repository
...Successfully got an update from the "bitnami" chart repository
...Successfully got an update from the "stable" chart repository
Update Complete. ⎈Happy Helming!⎈
Saving 1 charts
Downloading redis from repo https://charts.bitnami.com/bitnami
Deleting outdated charts

Check the subchart’s archive:

ll charts/
total 64
-rw-r--r-- 1 setevoy setevoy 64195 Oct 28 16:30 redis-11.2.3.tgz

Run again:

helm install backend-redis . --dry-run -f env/dev/values.yaml --debug

And if everything is good here – run the installation:

helm upgrade --install --namespace eks-dev-1-backend-redis-ns --create-namespace --atomic backend-redis . -f env/dev/values.yaml --set redis.global.redis.password=p@ssw0rd --debug
history.go:53: [debug] getting history for release backend-redis
Release "backend-redis" does not exist. Installing it now.
install.go:172: [debug] Original chart version: ""
install.go:189: [debug] CHART PATH: /home/setevoy/Work/devops-kubernetes/projects/backend/services/backend-redis
client.go:108: [debug] creating 1 resource(s)
client.go:108: [debug] creating 9 resource(s)
wait.go:53: [debug] beginning wait for 9 resources with timeout of 5m0s
wait.go:206: [debug] Service does not have load balancer ingress IP address: eks-dev-1-backend-redis-ns/backend-redis
wait.go:329: [debug] StatefulSet is not ready: eks-dev-1-backend-redis-ns/backend-redis-node. 1 out of 2 expected pods have been scheduled
...

Pay attention, that in the --set the password parameter also passed with the subchart’s name, and then the bloc’s name – redis.global.redis.password.

Check the services:

kk -n eks-dev-1-backend-redis-ns get svc
NAME                     TYPE           CLUSTER-IP       EXTERNAL-IP                                                                        PORT(S)                          AGE
backend-redis            LoadBalancer   172.20.153.106   internal-a5d0d8f5a5d4a4438a2ca06610886d2f-1400935130.us-east-2.elb.amazonaws.com   6379:30362/TCP,26379:31326/TCP   70s
backend-redis-headless   ClusterIP      None             <none>                                                                             6379/TCP,26379/TCP               70s
backend-redis-metrics    ClusterIP      172.20.50.77     <none>                                                                             9121/TCP                         70s                                                                      9121/TCP                         21s

Pods:

kk -n eks-dev-1-backend-redis-ns get pod
NAME                   READY   STATUS    RESTARTS   AGE
backend-redis-node-0   3/3     Running   0          37s
backend-redis-node-1   3/3     Running   0          21s

And check if Redis is working:

admin@bttrm-dev-app-1:~$ redis-cli -h internal-a5d0d8f5a5d4a4438a2ca06610886d2f-1400935130.us-east-2.elb.amazonaws.com -p 6379 -a p@ssw0rd info replication
Replication
role:master
connected_slaves:1
slave0:ip=10.3.45.195,port=6379,state=online,offset=15261,lag=1
...

Cool – now we can add a Jenkins job.

Here is everything similar to the jobs from the Helm: пошаговое создание чарта и деплоймента из Jenkins post (Rus).

Jenkins deploy job

Create a Jenkins Pipeline Job.

Parameters

Add parameters:

Тут будут:

  • APP_CHART_NAME: parent’s chart name
  • AWS_EKS_NAMESPACE: a Kubernetes Namespace to deploy to
  • AWS_EKS_CLUSTER: a Kubernetes cluster to deploy to, also used to generate the .kube/config for the kubectl
  • APP_ENV: used to substitute in the backend-redis/env/$APP_ENV/values.yaml and for the verify() function call, see the Jenkins: Scripted Pipeline – Production environment job confirmation step
  • APP_REPO_URL: the chart’s repository
  • APP_REPO_BRANCH: a branch in this repository

The directories structure in our repository is the following:

projects/
└── backend
└── services
└── backend-redis
├── Chart.lock
├── charts
│   └── redis-11.2.3.tgz
├── Chart.yaml
├── env
│   ├── dev
│   │   └── values.yaml
│   ├── prod
│   └── stage
├── templates
└── values.yaml

Create a  Password Parameter with a password for Redis:

Pipeline script

And write the pipeline script:

// ask confirmation for build if APP_ENV == prod
def verify() {

        def userInput = input(
            id: 'userInput', message: 'This is PRODUCTION!', parameters: [
            [$class: 'BooleanParameterDefinition', defaultValue: false, description: '', name: 'Please confirm you sure to proceed']
        ])
        
        if(!userInput) {
            error "Build wasn't confirmed"
        }
}

// Add slack Notification
def notifySlack(String buildStatus = 'STARTED') {

    // Build status of null means success.
    buildStatus = buildStatus ?: 'SUCCESS'

    def color
    //change for another slack chanel
    def token = 'devops-alarms-ci-slack-notification'

    if (buildStatus == 'STARTED') {
        color = '#D4DADF'
    } else if (buildStatus == 'SUCCESS') {
        color = '#BDFFC3'
    } else if (buildStatus == 'UNSTABLE') {
            color = '#FFFE89'
    } else {
        color = '#FF9FA1'
    }

    def msg = "${buildStatus}: `${env.JOB_NAME}` #${env.BUILD_NUMBER}:\n${env.BUILD_URL}"
    slackSend(color: color, message: msg, tokenCredentialId: token)
}

node {

    try { 

    docker.image('projectname/kubectl-aws:4.1').inside('-v /var/run/docker.sock:/var/run/docker.sock') {
        
        stage('Verify') {
           switch("${env.APP_ENV}") {
               case "prod":
                   verify()
                   echo "Run job"
                   break;
               default:
                   echo "Dev deploy"
                   break;
            }
        }

        stage('Init') {
            
            gitenv = git branch: '${APP_REPO_BRANCH}',
                         credentialsId: 'jenkins-projectname-github',
                         url: '${APP_REPO_URL}'
        
            GIT_COMMIT_SHORT = gitenv.GIT_COMMIT.take(8)
            RELEASE_VERSION = "${BUILD_NUMBER}"
            APP_VERSION = "${BUILD_NUMBER}.${GIT_COMMIT_SHORT}"
            AWS_EKS_REGION = "us-east-2"
            
            echo "APP_VERSION: ${APP_VERSION}"
            echo "RELEASE_VERSION: ${RELEASE_VERSION}"
            
            sh "aws eks update-kubeconfig --region ${AWS_EKS_REGION} --name ${AWS_EKS_CLUSTER}"
            sh "kubectl cluster-info"
            sh "helm version"
            sh "helm -n ${AWS_EKS_NAMESPACE} ls "
        }

        // install dependencies
        stage("Helm dependencies") {

            dir("projects/backend/services/${APP_CHART_NAME}") {
                sh "helm repo add bitnami https://charts.bitnami.com/bitnami"
                sh "helm dependency update"
            }
        }

        // lint the chart
        stage("Helm lint") {
            
            dir("projects/backend/services/") {
                sh "helm lint ${APP_CHART_NAME} -f ${APP_CHART_NAME}/env/${APP_ENV}/values.yaml"
            }
        }

        // just to create --app-version
        stage("Helm package") {

            dir("projects/backend/services/") {
                sh "helm package ${APP_CHART_NAME} --version ${RELEASE_VERSION} --app-version ${APP_VERSION}"
            }
        }
        
        // --dry-run first, if OK then run install
        stage("Helm install") {
            
            dir("projects/backend/services/") {
                sh "helm secrets upgrade --install --namespace ${AWS_EKS_NAMESPACE} --create-namespace --atomic ${APP_CHART_NAME} ${APP_CHART_NAME}-${RELEASE_VERSION}.tgz -f ${APP_CHART_NAME}/env/${APP_ENV}/values.yaml --set redis.global.redis.password=${REDIS_PASSWORD} --debug --dry-run"
                sh "helm secrets upgrade --install --namespace ${AWS_EKS_NAMESPACE} --create-namespace --atomic ${APP_CHART_NAME} ${APP_CHART_NAME}-${RELEASE_VERSION}.tgz -f ${APP_CHART_NAME}/env/${APP_ENV}/values.yaml --set redis.global.redis.password=${REDIS_PASSWORD} --debug"
            }
        }

        stage("Helm info") {
            
            dir("projects/backend/services/") {
                sh "helm ls -a -d --namespace ${AWS_EKS_NAMESPACE}"
                sh "helm get manifest --namespace ${AWS_EKS_NAMESPACE} ${APP_CHART_NAME}"
            }
        }
    }

    // send Slack notification if Jenkins build fails
    } catch (e) {
        currentBuild.result = 'FAILURE'
        notifySlack(currentBuild.result)
        throw e
    }
}

Slack notifications are described in the Jenkins: уведомление в Slack из Jenkins Scripted Pipeline post (Rus).

Run the Job:

Check the result:

helm -n eks-dev-1-backend-redis-ns ls
NAME            NAMESPACE                       REVISION        UPDATED                                 STATUS          CHART                   APP VERSION
backend-redis   eks-dev-1-backend-redis-ns      2               2020-10-29 14:19:52.407047243 +0000 UTC deployed        backend-redis-13        13.6da15d3e

Done.



Also published on Medium.