Github Action workflow to deploy flask application on Google Kubernetes Engine (GKE)

 Deploy application on GKE using Github Actions

Follow the below steps to setup Github Actions workflow.

Prerequisite:

- Create service account in GCP and generate key file.

- Convert key file into base64 format and using the output to create secret variable in github repo.

Steps:

- In your github repo create .github/workflow directory

- Under workflow directory create a file called deploy.yml and paste below code into it.

name: Build-Deploy

on:

  push:

    branches: [ "anup_gke" ]

env:

  PROJECT_ID: <google-project-id> # ${{ secrets.GKE_PROJECT }}

  GKE_CLUSTER: <GKE-Cluster-name>    # TODO: update to cluster name

  GKE_ZONE: us-central1-a   # TODO: update to cluster zone

  DEPLOYMENT_NAME: gke-test # TODO: update to deployment name

  IMAGE_FLASK: <image name>

  IMAGE_NGINX: <image name>

jobs:

  build-deploy-gke:

    name: Login, Build, Publish, and Deploy

    runs-on: ubuntu-latest

    steps:

    - name: Checkout

      uses: actions/checkout@v3

    - id: 'auth'

      name: Google Authentication

      uses: 'google-github-actions/auth@v1'

      with:

        credentials_json: '${{ secrets.GKE_SA_KEY }}'

    # Setup gcloud CLI

    - uses: google-github-actions/setup-gcloud@v1

      name: Setup gcloud CLI

    # Configure Docker to use the gcloud command-line tool as a credential

    # helper for authentication

    - name: 'Configure Docker to use the gcloud command-line tool'

      run: |-

        gcloud --quiet auth configure-docker

    # Build the Docker image for mvp-flask

    - name: Build Docker Image of mvp-flask

      run: |-

        cd source/mvp-flask

        docker build -t gcr.io/$PROJECT_ID/$IMAGE_FLASK:$GITHUB_RUN_ID .

    # Build the Docker image for mvp-nginx

    - name: Build Docker Image of mvp-nginx

      run: |-

        cd source/nginx

        docker build -t gcr.io/$PROJECT_ID/$IMAGE_NGINX:$GITHUB_RUN_ID .

    - name: Push docker images to GCR

      run: |-

        docker push gcr.io/$PROJECT_ID/$IMAGE_FLASK:$GITHUB_RUN_ID

        docker push gcr.io/$PROJECT_ID/$IMAGE_NGINX:$GITHUB_RUN_ID

    - name: 'Get GKE Credentails'

      id: 'get-credentials'

      uses: 'google-github-actions/get-gke-credentials@v1'

      with:

        cluster_name: ${{ env.GKE_CLUSTER }}

        location: ${{ env.GKE_ZONE }}

    - name: Deploy Docker Image on GKE Cluster

      run: |-

        kubectl set image deployment.apps/mvp-flask flask=gcr.io/<google-project-id>/$IMAGE_FLASK:$GITHUB_RUN_ID

        kubectl set image deployment.apps/mvp-nginx nginx=gcr.io/<google-project-id>/$IMAGE_NGINX:$GITHUB_RUN_ID

    - name: command

      run: |-

        kubectl get all

        echo "###"

        kubectl describe deployment.apps/mvp-flask

        echo "###"

        kubectl describe deployment.apps/mvp-nginx