forage-flask-app¶

Deploy flask app to GKE using GitHub Actions¶

1) Configure GCP details in github repo

        Project id - Add it as github secret with name GKE_PROJECT
        Service Account - Add it as github secret with name GKE_SA_KEY

2) Configure k8 objects with GCP Infra details (pre-created)

        deployment.yml 
        - For gke-test container, configure DB credentials in secret "postgres-secret"
        - For side car, configure CloudSQL connection name in command
        - For side car, map k8 secret "cloudsql-sa" to volume "sa-volume" at mountPath "/secrets/"

        If for some reason you want a new service
            kubectl expose deployment gke-test --type=LoadBalancer --port 80 --target-port 8080

3) Setup gitactions (Reference: https://github.com/google-github-actions/setup-gcloud/blob/master/example-workflows/gke/README.md)

        gke.yml
        - Set GKE_ZONE 
        - Change triggers based on requirement (here we trigger for evey merge/push to main branch)
            on>push>branches

4) Configure SQLALCHEMY_DATABASE_URI to localhost as we use CLoud SQL Proxy side car

        127.0.0.1:5432

Validate deployment¶

1) Check status on github actions

2) Verify k8 objects

        gcloud container clusters get-credentials <cluster name> --region=<cluster region>
        kubectl get namespace
        kubectl get pod
        kubectl get services  (use external ip to access)
        kubectl logs [POD] -c gke-test
        kubectl exec [POD] -- [COMMAND]

3) Access application :-)

        GET at http://<external ip shown by service>/

        ![Alt text](<https://github.com/msashish/forage-flask-app/blob/main/get_request.png>)

        POST at http://<external ip shown by service>/

        ![Alt text](<https://github.com/msashish/forage-flask-app/blob/main/post_request.png>)

Local setup¶

Setup postgresql locally¶

    Install postgresql from https://postgresapp.com/
    create a DB as below [terminal] 
        psql
        create database demo_user;
        \q

Create table by using SQLALCHEMY's migrate feature¶

    export SQLALCHEMY_DATABASE_URI="postgresql:///demo_user" 
    python manage.py db init
    python manage.py db migrate
    python manage.py db upgrade  (to apply changes)
    python initial_data_load.py  (to insert some sample data)

Check table data manually [terminal]¶

    psql
    \c demo_user
    \dt
    select * from demo_users;

Test running flask app locally¶

    python -m flask run (Dont use flask run as it triggers cli.py from outside of venv)
    Check at http://127.0.0.1:5000/ either through Postman for POST and GET

    or run gunicorn
    gunicorn app:app
    Check at  http://127.0.0.1:8000/