linode / apl-example-app

Example distributed app composed of multiple containers

apl-example-app

This repo contains the source code to build the vote, worker and results images for deploying the the APL Example App - based on the Example Voting App - using the provided quickstart Helm charts in the APL Catalog.

Get started

Building the images

Use the Build feature in Otomi to build the images with Docker mode for the result,vote and worker components:

1. Set the build name (ex. voting-app-vote)
2. Set the Repo URL to https://github.com/redkubes/example-voting-app.git
3. Set the path to ./vote/Dockerfile
4. Repeat step 1,2 and 3 for the other 2 components
   • use ./result/Dockerfile and ./worker/Dockerfile paths respectively

Create a Redis cluster and a PostgreSQL database

Use the postgresql and the redis charts in the APL Catalog to create a Redis master-replica cluster and a PostgreSQL database.

• Postgresql:
  • Name: <postgesql app name> (E.g.voting-app-psql).
  • Click Submit (can use default values for this example)
• Redis:
  • Name: <redis app name> (E.g.voting-app-redis).
  • For this demo, Redis authentication needs to be turned off by setting

    auth:
    enabled: false

    in the chart Values editor.
  • Click Submit and then Deploy

Deploy the Vote app

Use the k8s-deployment chart to deploy the vote app. Use the following values:

• Name: voting-app-vote
• Update Values:

  containerPorts:
    - name: http
      containerPort: 80
      protocol: TCP
  env:
    - name: REDIS_HOST
      value: <redis-cluster-name>-master # E.g. voting-app-redis-master

• Click Submit

Deploy the Worker app

Use the k8s-deployment chart to deploy the worker app. Use the following values:

• Name: voting-app-worker
• Update Values:

  containerPorts:
    - name: http
      containerPort: 80
      protocol: TCP
  env:
    - name: DATABASE_USER
      valueFrom:
        secretKeyRef:
          name: <psql-cluster-name>-superuser # E.g. voting-app-psql-superuser
          key: username
    - name: DATABASE_PASSWORD
      valueFrom:
        secretKeyRef:
          name: <psql-cluster-name>-superuser # E.g. voting-app-psql-superuser
          key: password
    - name: REDIS_HOST
      value: <redis-cluster-name>-master      # E.g. voting-app-redis-master
    - name: DATABASE_HOST
      value: <psql-cluster-name>-rw           # E.g. voting-app-psql-rw

• Click Submit

Deploy the Result app

Use the k8s-deployment chart to deploy the result app. Use the following values:

• Name: voting-app-result
• Update Values:

  containerPorts:
    - name: http
      containerPort: 80
      protocol: TCP
  env:
    - name: DATABASE_USER
      valueFrom:
        secretKeyRef:
          name: <psql-cluster-name>-superuser # E.g. voting-app-psql-superuser
          key: username
    - name: DATABASE_PASSWORD
      valueFrom:
        secretKeyRef:
          name: <psql-cluster-name>-superuser # E.g. voting-app-psql-superuser
          key: password
    - name: DATABASE_HOST
      value: <psql-cluster-name>-rw           # E.g. voting-app-psql-rw

• Click Submit and then Deploy

Register the services

Register the vote and result services in APL and configure them for external exposure.

Vote

• Register the vote service
• Set exposure to External
• Click Submit

Result

• Register the result service
• Set exposure to External
• Click Submit and then Deploy

Network Policies

If Network policies are enabled, then register all services and configure the network policies:

Postgres Database

• Create a new Netpol and select the ingress rule type
• Add the selector label name otomi.io/app
• Add the selector label value <postgres-workload-name> (E.g. voting-app-psql)
• Select AllowOnly
• Add the namespace <team-name> (E.g. team-demo), the selector label name otomi.io/app and the selector label value <worker> (E.g. voting-app-worker)
• Add the namespace <team-name> (E.g. team-demo), the selector label name otomi.io/app and the selector label value <result> (E.g. voting-app-result)
• Click Submit

Redis

• Create a new network policy and select the ingress rule type
• Add the selector label name otomi.io/app
• Add the selector label value <redis-workload-name> (E.g. voting-app-redis)
• Select AllowOnly
• Add the namespace <team-name> (E.g. team-demo), the selector label name otomi.io/app and the selector label value <worker> (E.g. voting-app-worker)
• Add the namespace <team-name> (E.g. team-demo), the selector label name otomi.io/app and the selector label value <vote> (E.g. voting-app-vote)
• Click Submit and then Deploy