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Creating a micro service architecture

In this tutorial we are going to deploy multiple services from different teams and expose them using a shared domain, but each on their own path. We will use on-the-fly Knative services for speed and simplicity.

Prerequisites​

  1. You are familiar with Knative
  2. Knative is enabled in Otomi. (Check the Apps section under Platform.)
  3. Two teams are created. We will refer to them as alpha and beta. (It is not necessary to Deploy first.)

Instructions​

  1. Select team alpha in the top bar, select Services from the Team alpha menu section and click on Create Service, and choose New knative service.

  2. Provide the following values and submit:

  • name: sir
  • Run As User: 1001
  • Repository: otomi/nodejs-helloworld
  • Tag: v1.2.12
  • Limits: CPU=100m, Memory=128Mi
  • Requests: CPU=50m, Memory=64Mi
  • env: TARGET=world, I just woke up!, SERVANTS=servant-1,servant-2
  • Check Scale to zero
  • Exposure: Ingress
  • Uncheck Use team domain
  • host: hello-multi (DNS zone can be left as-is)

Click Deploy to start the service and domain registration, as that might take time. Plus we want the service to go to sleep as we intend to wake it up later (it serves a purpose, hope you spot it later on ;).

  1. Under the same team create the last New knative service service with the same values but the following diff and submit:
  • name: informant
  • Exposure: Cluster
  • Leave Scale to zero unchecked
  1. Under the same team create another New knative service service with the same values but with the following diff and submit:
  • name: servant-1
  • paths: /servant-1
  • env: TARGET=sir
  1. Select team beta and create a New knative service service with the same values but the following diff and submit:
  • name: servant-2
  • paths: /servant-2
  • env: TARGET=sir, INFORMANT=http://informant.team-alpha
  1. Now click Deploy Changes again and watch the deployment finish in Drone.

Conclusion​

In effect what we have done is create the following workloads for team alpha:

  • master.team-alpha exposed via https://hello-multi.$domain
  • servant-1.team-alpha exposed via https://hello-multi.$domain/servant-1
  • informant.team-alpha not exposed publicly, but only able to receive requests from servant-2.team-beta.

And for team beta:

  • servant-2.team-beta exposed via https://hello-multi.$domain/servant-2

Bonus: Add network policies to make sure no unforeseen traffic is routed :)