Add conformance test (#1)

.github/workflows/pull_request.yaml

@@ -1,9 +1,9 @@
-name: Test conformance
+name: Test
 
 on: pull_request
 
 jobs:
-  create-cluster:
+  test:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
@@ -24,7 +24,7 @@ jobs:
       - name: Build Go binary
         run: |
           cd ./conformance
-          go build -ldflags "-s -w" -o conformance .
+          go build -ldflags "-s -w" -o bin/conformance .
         env:
           GOOS: linux
           GOARCH: amd64
@@ -41,12 +41,13 @@ jobs:
         uses: docker/build-push-action@v2
         with:
           context: ./conformance
+          push: true
           tags: ghcr.io/castai/k8s-client-go/conformance:${{ github.sha }}
 
       - name: Create k8s cluster
         uses: helm/kind-action@v1.3.0
 
-      - name: Run conformance
+      - name: Run tests
         run: |
           cd ./conformance
-          ./run.sh
+          IMG=ghcr.io/castai/k8s-client-go/conformance:${{ github.sha }} ./run.sh

README.md

@@ -1,3 +1,34 @@
 # k8s-client-go
 
-Minimal Go Kubernetes client
+Minimal Go Kubernetes client based on Generics
+
+## Usage
+
+```go
+import (
+    "context"
+    "log"
+    "fmt"
+    client "github.com/castai/k8s-client-go"
+)
+
+func main() {
+    kc, err := client.NewInCluster()
+    if err != nil {
+        log.Fatal(err)
+    }
+    ctx := context.Backgroud()
+    endpoints, err := client.Get[*client.Endpoints](kc, ctx, "/api/v1/namespaces/kube-system/endpoints/kubelet", client.GetOptions{})
+    if err != nil {
+        log.Fatal(err)
+    }
+    fmt.Printf("%+v", endpoints)
+}
+```
+
+See more in [Examples](https://github.com/castai/k8s-client-go/blob/master/client_test.go#L10)
+
+## Use cases
+
+* Embedding in Go applications for minimal binary size overhead.
+* Service discovery by listing and watching [endpoints](https://kubernetes.io/docs/reference/kubernetes-api/service-resources/endpoints-v1/). See [kuberesolver](https://github.com/sercand/kuberesolver) as example for gRPC client side load balancing.

client_test.go

@@ -11,13 +11,33 @@ func ExampleClient() {
 	kc, err := client.NewInCluster()
 	if err != nil {
 		// Handle err
+		return
 	}
 
 	ctx := context.Background()
-	endpoints, err := client.GetEndpoints(kc, ctx, "kube-system", "kubelet", client.GetOptions{})
+
+	// Generic get.
+	endpoints, err := client.Get[*client.Endpoints](kc, ctx, "/api/v1/namespaces/kube-system/endpoints/kubelet", client.GetOptions{})
 	if err != nil {
 		// Handle err
+		return
 	}
 
+	// Typed methods. Simple wrapper for Get.
+	endpoints, err = client.GetEndpoints(kc, ctx, "kube-system", "kubelet", client.GetOptions{})
+	if err != nil {
+		// Handle err
+		return
+	}
 	fmt.Printf("%+v", endpoints)
+
+	// Watch support.
+	events, err := client.Watch[*client.Endpoints](kc, ctx, "/api/v1/namespaces/kube-system/endpoints/kubelet", client.ListOptions{})
+	if err != nil {
+		// Handle err
+		return
+	}
+	for event := range events.ResultChan() {
+		fmt.Println(event.Type, event.Object)
+	}
 }

conformance/job.yaml

@@ -24,6 +24,9 @@ metadata:
   namespace: conformance
 spec:
   template:
+    metadata:
+      labels:
+        app: conformance
     spec:
       serviceAccount: conformance
       containers:

conformance/main.go

@@ -58,6 +58,7 @@ func testEndpoints(nativeClient *kubernetes.Clientset, kc *client.Client) error
 	}
 
 	compare := func(a *corev1.Endpoints, b *client.Endpoints) error {
+		fmt.Printf("compare endpoints:\na=%+v\nb=%+v\n", a, b)
 		ip1 := a.Subsets[0].Addresses[0].IP
 		ip2 := b.Subsets[0].Addresses[0].IP
 		if ip1 != ip2 {
@@ -92,8 +93,10 @@ func testEndpoints(nativeClient *kubernetes.Clientset, kc *client.Client) error
 				deleted = true
 			}
 			if added && deleted {
-				a = event.Object.(*corev1.Endpoints)
-				e.Stop()
+				if v, ok := event.Object.(*corev1.Endpoints); ok {
+					a = v
+					e.Stop()
+				}
 			}
 		}
 		return nil

conformance/run.sh

@@ -11,7 +11,17 @@ if [ "$IMG" == "" ]; then
     docker push ${img}
 fi
 
+function log()
+{
+    echo "Test failed!"
+    echo "Pods:"
+    kubectl get pods -owide -n conformance
+    echo "Logs:"
+    kubectl logs -l app=conformance -n conformance
+}
+trap log ERR
+
 kubectl delete ns conformance || true
 kubectl create ns conformance
-kubectl apply -f job.yaml --dry-run=client -oyaml | sed "s/replace-img/$(echo "$img" | sed 's/\//\\\//g')/" | kubectl apply -f -
-kubectl wait --for=condition=complete --timeout=10s job/conformance
+kubectl apply -f job.yaml --dry-run=client -oyaml | sed "s/replace-img/$(echo "$img" | sed 's/\//\\\//g')/" | kubectl apply -f - -n conformance
+kubectl wait --for=condition=complete --timeout=10s job/conformance -n conformance