Add replicaset helper functions (#804)

Update test names

Fix names

Update test YAML

Update label

modules/k8s/replicaset.go

@@ -0,0 +1,49 @@
+package k8s
+
+import (
+	"context"
+
+	"github.com/stretchr/testify/require"
+	appsv1 "k8s.io/api/apps/v1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+
+	"github.com/gruntwork-io/terratest/modules/testing"
+)
+
+// ListReplicaSets will look for replicasets in the given namespace that match the given filters and return them. This will
+// fail the test if there is an error.
+func ListReplicaSets(t testing.TestingT, options *KubectlOptions, filters metav1.ListOptions) []appsv1.ReplicaSet {
+	replicaset, err := ListReplicaSetsE(t, options, filters)
+	require.NoError(t, err)
+	return replicaset
+}
+
+// ListReplicaSetsE will look for replicasets in the given namespace that match the given filters and return them.
+func ListReplicaSetsE(t testing.TestingT, options *KubectlOptions, filters metav1.ListOptions) ([]appsv1.ReplicaSet, error) {
+	clientset, err := GetKubernetesClientFromOptionsE(t, options)
+	if err != nil {
+		return nil, err
+	}
+	replicasets, err := clientset.AppsV1().ReplicaSets(options.Namespace).List(context.Background(), filters)
+	if err != nil {
+		return nil, err
+	}
+	return replicasets.Items, nil
+}
+
+// GetReplicaSet returns a Kubernetes replicaset resource in the provided namespace with the given name. This will
+// fail the test if there is an error.
+func GetReplicaSet(t testing.TestingT, options *KubectlOptions, replicaSetName string) *appsv1.ReplicaSet {
+	replicaset, err := GetReplicaSetE(t, options, replicaSetName)
+	require.NoError(t, err)
+	return replicaset
+}
+
+// GetReplicaSetE returns a Kubernetes replicaset resource in the provided namespace with the given name.
+func GetReplicaSetE(t testing.TestingT, options *KubectlOptions, replicaSetName string) (*appsv1.ReplicaSet, error) {
+	clientset, err := GetKubernetesClientFromOptionsE(t, options)
+	if err != nil {
+		return nil, err
+	}
+	return clientset.AppsV1().ReplicaSets(options.Namespace).Get(context.Background(), replicaSetName, metav1.GetOptions{})
+}

modules/k8s/replicaset_test.go

@@ -0,0 +1,87 @@
+// +build kubeall kubernetes
+
+// NOTE: we have build tags to differentiate kubernetes tests from non-kubernetes tests. This is done because minikube
+// is heavy and can interfere with docker related tests in terratest. Specifically, many of the tests start to fail with
+// `connection refused` errors from `minikube`. To avoid overloading the system, we run the kubernetes tests and helm
+// tests separately from the others. This may not be necessary if you have a sufficiently powerful machine.  We
+// recommend at least 4 cores and 16GB of RAM if you want to run all the tests together.
+
+package k8s
+
+import (
+	"fmt"
+
+	"strings"
+	"testing"
+
+	"github.com/gruntwork-io/terratest/modules/random"
+	"github.com/stretchr/testify/require"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+)
+
+func TestGetReplicaSetEReturnsError(t *testing.T) {
+	t.Parallel()
+
+	options := NewKubectlOptions("", "", "")
+	_, err := GetReplicaSetE(t, options, "sample-rs")
+	require.Error(t, err)
+}
+
+func TestGetReplicaSets(t *testing.T) {
+	t.Parallel()
+
+	uniqueID := strings.ToLower(random.UniqueId())
+	options := NewKubectlOptions("", "", uniqueID)
+	configData := fmt.Sprintf(EXAMPLE_REPLICASET_YAML_TEMPLATE, uniqueID, uniqueID)
+	KubectlApplyFromString(t, options, configData)
+	defer KubectlDeleteFromString(t, options, configData)
+
+	replicaSet := GetReplicaSet(t, options, "sample-rs")
+	require.Equal(t, replicaSet.Name, "sample-rs")
+	require.Equal(t, replicaSet.Namespace, uniqueID)
+}
+
+func TestListReplicaSets(t *testing.T) {
+	t.Parallel()
+
+	uniqueID := strings.ToLower(random.UniqueId())
+	options := NewKubectlOptions("", "", uniqueID)
+	configData := fmt.Sprintf(EXAMPLE_REPLICASET_YAML_TEMPLATE, uniqueID, uniqueID)
+	KubectlApplyFromString(t, options, configData)
+	defer KubectlDeleteFromString(t, options, configData)
+
+	replicaSets := ListReplicaSets(t, options, metav1.ListOptions{})
+	require.Equal(t, len(replicaSets), 1)
+
+	replicaSet := replicaSets[0]
+	require.Equal(t, replicaSet.Name, "sample-rs")
+	require.Equal(t, replicaSet.Namespace, uniqueID)
+}
+
+const EXAMPLE_REPLICASET_YAML_TEMPLATE = `---
+apiVersion: v1
+kind: Namespace
+metadata:
+  name: %s
+---
+apiVersion: apps/v1
+kind: ReplicaSet
+metadata:
+  name: sample-rs
+  namespace: %s
+  labels:
+    app: sample-rs
+spec:
+  selector:
+    matchLabels:
+      name: sample-rs
+  template:
+    metadata:
+      labels:
+        name: sample-rs
+    spec:
+      containers:
+      - name: alpine
+        image: alpine:3.8
+        command: ['sh', '-c', 'echo Hello Terratest! && sleep 99999']
+`