kube-server

This is a Go based REST server that interacts with the Kubernetes API, specifically with Deployments and their replicas.

Prerequisites

• Go
• minikube
• Helm
• kubectl

Usage

For a quickstart you can make start This will:

• Build the kube-server binary for Linux 64-bit
• Start the minikube container and give you a kubeconfig
• Builds a kube-server docker image within minikube for local use
• Creates self-signed certs for mTLS for kube-server and Redis
• Creates multiple demonstration Deployments in minikube
• Deploys the certificates as secrets in the kube-server and Redis namespaces
• Installs Redis helm chart
• Installs local kube-server helm chart

It may take a couple moments for Redis to initialize. When it's healthy you can access the kube-server with an mTLS wrapper script.

Here's some examples using the script:

./scripts/client-tls.sh https://localhost:8443/v1/healthz
./scripts/client-tls.sh https://localhost:8443/v1/deployments
./scripts/client-tls.sh https://localhost:8443/v1/replicas/busybox-test/busybox-deployment
./scripts/client-tls.sh -X POST https://localhost:8443/v1/replicas/busybox-test/busybox-deployment -H 'Content-Type: application/json' -d '{replica_size:5}'
./scripts/client-tls.sh https://localhost:8443/v1/replicas/busybox-test/busybox-deployment 

Local Development

For local development you can use the following workflow:

1. Initialize with minikube start
2. Make changes to the code
3. Use go run-dev to spawn a server in your teminal
4. Use https://localhost:8888 to send requests to test
5. Run unit-tests make unit-tests
6. Deploy to minikube with make deploy
7. curl endpoints you want to test
8. Run integration test make int-tests

Endpoints

Here's the available endpoints

v1/healthz

GET

Response

{
  "http_response_code": 200,
  "kubernetes_api_status": "ok",
  "application_version": "0.1.0"
}

v1/deployments

You can also filter deployments by namespace like: /v1/replicas/deployments?namespace=busybox-test

GET

Response

{
  "http_response_code": 200,
  "deployments": [
    {
      "deployment_name": "busybox-deployment0",
      "namespace": "busybox-test"
    },
    {
      "deployment_name": "busybox-deployment1",
      "namespace": "busybox-test"
    },
  ]
}

v1/replicas/:namespace/:deployment

GET

Gets the replicas of the specified deployment.

Response

{
  "namespace": "busybox-test",
  "deployment_name": "busybox-deployment0",
  "current_replicas": 5,
  "desired_replicas": 5,
  "state_drift": false,
  "http_status_code": 200
}

POST

Sets the replicas of the specified deployment.

Request

{
    "replica_size":4
}

Response

{
  "namespace": "busybox-test",
  "deployment_name": "busybox-deployment0",
  "current_replicas": 5,
  "desired_replicas": 5,
  "requested_replicas": 4,
  "state_drift": false,
  "http_status_code": 200
}