NOTE: A revised version of this workshop is available at https://github.com/William-Yeh/workshop-gcpug201906

Store config in the environment (aka the 12-factor app principles).

Public accessible endpoint for todoapi backend, defined in config.local.yml:

• TODOAPI_HOST : default = localhost
• TODOAPI_PORT : default = 30080
• TODOAPI_PATH : default = /api/todo

A version for deployment on the cloud is also provided in config.test.yml:

• TODOAPI_HOST : external IP (ephemeral or static) or domain name allocated by cloud providers.
• TODOAPI_PORT : default = 80
• TODOAPI_PATH : default = /api/todo

A dockerized web app with separate frontend and backend services on Kubernetes (both locally and on the cloud).

Frontend

Static HTML5 files and jQuery scripts.

Local web endpoint:

• host = localhost
• port = 30000

Cloud web endpoint:

• host = external IP (ephemeral or static) or domain name allocated by cloud providers
• port = 80

Backend

Backend program written in ASP.NET Core. Two versions are provided: stable version and canary version.

Local API endpoint:

• host = localhost
• port = TODOAPI_PORT (default = 30080)
• path = TODOAPI_PATH (default = /api/todo)

Cloud API endpoint:

• host = TODOAPI_HOST (to be revised in config.test.yml), external IP (ephemeral or static) or domain name allocated by cloud providers
• port = TODOAPI_PORT (default = 80)
• path = TODOAPI_PATH (default = /api/todo)

1. If you're using GKE, do the gke-steps first.

2. Create a todo namespace for this app:

   % kubectl create ns todo
   

3. Load the ConfigMap content, if the workshop is to be run locally:

   % kubectl apply -f k8s/local/config.local.yml  -n todo
   % kubectl get configmaps  -n todo
   

4. Load the ConfigMap content, if the workshop is for test on the cloud (GCP/GKE for example):

   # reserve a new static external IP address for backend todoapi
   % gcloud compute addresses create todoapi --region=us-west1 --network-tier=PREMIUM
   
   # make sure the static external IP address has been allocated
   % gcloud compute addresses list
   
   # replace the placeholder string "111.222.333.444" with the allocated IP address
   % vi k8s/test/config.test.yml
   % vi k8s/test/todoapi-service.yml
   
   #...
   
   # now, load it!
   % kubectl apply -f k8s/test/config.test.yml  -n todo
   % kubectl get configmaps  -n todo
   

5. Fill in correct image names by modifying the PROJECT_ID string in the following files:

   • docker-compose.yml
   • k8s/local/todoapi-service.yml
   • k8s/local/todoapi-canary-deployment.yml
   • k8s/local/todofrontend-service.yml
   • k8s/test/todoapi-service.yml
   • k8s/test/todoapi-canary-deployment.yml
   • k8s/test/todofrontend-service.yml

1. Build images:

   % docker-compose build
   

If you're running the workshop on the cloud, be sure to push the images to registry (GCR for example):

% docker push gcr.io/PROJECT_ID/

1. Change working directory to k8s/local.

   % cd k8s/local
   

2. Start the backend:

   % kubectl apply -f todoapi-service.yml -n todo
   % kubectl get svc  -n todo
   

3. Start the frontend:

   % kubectl apply -f todofrontend-service.yml -n todo
   % kubectl get svc  -n todo
   

4. Use your browser to visit the web app at http://localhost:30000

The same as the local stage, except that:

• Change working directory to k8s/test.

• Use your browser to visit the web app at http://FRONTEND_EXTERNAL_IP:80

1. See the number of pods in the deployment:

   % kubectl get deployments -n todo
   NAME      DESIRED   CURRENT   UP-TO-DATE   AVAILABLE   AGE
   todoapi   3         3         3            3           4m
   

2. Launch the canary part of the todoapi service:

   % kubectl apply -f todoapi-canary-deployment.yml -n todo
   

3. See again the number of pods in the deployments, including the canary part:

   % kubectl get deployments -n todo
   NAME             DESIRED   CURRENT   UP-TO-DATE   AVAILABLE   AGE
   todoapi          3         3         3            3           5m
   todoapi-canary   1         1         1            1           44s
   

4. Scale the canary part:

   % kubectl patch deployment todoapi-canary \
       --patch "$(cat todoapi-canary-patch.yml)" -n todo
   

5. See again the number of pods in the deployments, including the canary part:

   % kubectl get deployments -n todo
   NAME             DESIRED   CURRENT   UP-TO-DATE   AVAILABLE   AGE
   todoapi          3         3         3            3           7m
   todoapi-canary   2         2         2            2           2m
   

See here if you'd like to use Kubernetes dashboard locally.

The sample was extracted from the TodoApi demo in the Microsoft Docs site, retrieved on Feb 14, 2019:

• Document - Tutorial: Create a web API with ASP.NET Core MVC

• Source code - https://github.com/aspnet/Docs/tree/master/aspnetcore/tutorials/first-web-api/samples/2.2/TodoApi

The original source code to be used in this repo is packed in the TodoApi-original.zip file for your reference.

Apache License 2.0. See the LICENSE file.

7.0: Support canary release.

6.0: Support Kubernetes on the cloud (GKE for example).

5.0: Support ConfigMap and naming convention.

4.1: Use Kubernetes dashboard.

4.0: Support Kubernetes (locally).

3.0: Separate frontend and backend into 2 distinct containers.

2.0: Dockerize the app with simple Dockerfile and docker-compose.yml.

1.0: Extracted from Microsoft Docs.