README.md

Lab: Helm Setup and Deploy Application

In this lab we will setup Helm in our AKS cluster and deploy our application with Helm charts.

Prerequisites

• Helm Version 3+
• Clone this repo in Azure Cloud Shell.
• Complete previous labs:
  • Azure Kubernetes Service
  • Build Application Components in Azure Container Registry

Instructions

Note: The following lab assumes Helm version 3. Run the following to confirm your Helm version:

helm version

# Example Output:
version.BuildInfo{Version:"v3.0.0", GitCommit:"e29ce2a54e96cd02ccfce88bee4f58bb6e2a28b6", GitTreeState:"clean", GoVersion:"go1.13.4"}

1. Review the Helm Chart components

   In this repo, there is a folder for charts with a sub-folder for each specific app chart. In our case each application has its own chart.

   The values.yaml file has the parameters that allow you to customize release. This file has the defaults, but they can be overridden on the command line.

   The templates folder holds the yaml files for the specific kubernetes resources for our application. Here you will see how Helm inserts the parameters into resources with this bracketed notation: eg - {{.Values.deploy.image}}

2. Customize Chart Parameters

   In each chart we will need to update the values file with our specific Azure Container Registry.

   • Get the value of your ACR Login Server:

     az acr list -o table --query "[].loginServer"
     
     Result
     -------------------
     youracr.azurecr.io
     

   • Replace the acrServer value below with the Login server from previous step. In the Azure Cloud Shell, select the file editor '{}'. Navigate to the yaml files below. To save changes, select the elipticals on the right hand side and select Save. You will make this change in all of the charts below (except cache-api)

     charts/service-tracker-ui/values.yaml

     charts/weather-api/values.yaml

     charts/flights-api/values.yaml

     charts/quakes-api/values.yaml

     charts/data-api/values.yaml

     Example:

     # Default values for chart
     
     service:
     type: ClusterIP
     port: 3009
     
     deploy:
     name: data-api
     replicas: 1
     acrServer: "youracr.azurecr.io"
     imageTag: "1.0"
     containerPort: 3009

   • Validate that the imageTag parameter matches the tag you created in Azure Container Registry in the previous lab.

   • Add imagePullSecret to each deployment.yaml file for each microservice

     NOTE: Only do if the Service Principal role assignment in Build Application lab failed. You will need to add the Docker Registry secret that was created to each deployment via a mechanism called an imagePullSecret.

     charts/service-tracker-ui/templates/deployment.yaml

     charts/weather-api/templates/deployment.yaml

     charts/flights-api/templates/deployment.yaml

     charts/quakes-api/templates/deployment.yaml

     charts/data-api/templates/deployment.yaml

     Example Before:

     ...
     
     containers:
       - image: "{{.Values.deploy.acrServer}}/hackfest/weather-api:{{.Values.deploy.imageTag}}"
         imagePullPolicy: Always
     
     ...

     Example After (2 imagePullSecrets lines added):

     ...
     
     imagePullSecrets:
     - name: regcred
     containers:
       - image: "{{.Values.deploy.acrServer}}/hackfest/weather-api:{{.Values.deploy.imageTag}}"
         imagePullPolicy: Always
     
     ...

3. Deploy Charts

   Ensure namespace was created earlier:

   kubectl get ns hackfest
   
   NAME       STATUS    AGE
   hackfest   Active    4m

   Install each chart as below:

   # Application charts
   
   helm upgrade --install data-api charts/data-api --namespace hackfest
   helm upgrade --install quakes-api charts/quakes-api --namespace hackfest
   helm upgrade --install weather-api charts/weather-api --namespace hackfest
   helm upgrade --install flights-api charts/flights-api --namespace hackfest
   helm upgrade --install service-tracker-ui charts/service-tracker-ui --namespace hackfest

4. Initialize application

   • First check to see if pods and services are working correctly

   kubectl get pod,svc -n hackfest
   
   NAME                                     READY   STATUS    RESTARTS   AGE
   pod/data-api-5bdc5c94b4-8xfq2            1/1     Running   3          5d3h
   pod/flights-api-77f77464df-n7jb4         1/1     Running   4          5d15h
   pod/quakes-api-7c8b96b594-vm5qd          1/1     Running   4          5d15h
   pod/service-tracker-ui-c4476d778-hpn5q   1/1     Running   3          5d6h
   pod/weather-api-56d6c57b89-cds8v         1/1     Running   4          5d15h
   
   NAME                         TYPE           CLUSTER-IP     EXTERNAL-IP   PORT(S)          AGE
   service/data-api             ClusterIP      10.0.179.206   <none>        3009/TCP         7d4h
   service/flights-api          ClusterIP      10.0.255.59    <none>        3003/TCP         7d4h
   service/quakes-api           ClusterIP      10.0.122.46    <none>        3012/TCP         7d4h
   service/service-tracker-ui   LoadBalancer   10.0.24.184    40.71.20.1    8080:30757/TCP   5d6h
   service/weather-api          ClusterIP      10.0.124.80    <none>        3015/TCP         7d4h

   • Browse to the web UI

   kubectl get service service-tracker-ui -n hackfest
   
   NAME                 TYPE           CLUSTER-IP    EXTERNAL-IP   PORT(S)          AGE
   service-tracker-ui   LoadBalancer   10.0.24.184   40.71.20.1    8080:30757/TCP   5d6h

   Open the browser to http://40.71.20.1:8080 (your IP will be different #obvious)

   • You will need to click "REFRESH DATA" for each service to load the data sets.

     

   • Browse each map view and have some fun.

Troubleshooting / Debugging

• Make sure Helm version on the client and server are the same to ensure compatibility.

Docs / References

• Helm

Next Lab: CI/CD Automation