package vkubelet

import (
	"context"
	"sort"
	"testing"

	gocmp "github.com/google/go-cmp/cmp"
	"gotest.tools/assert"
	is "gotest.tools/assert/cmp"
	corev1 "k8s.io/api/core/v1"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"

	testutil "github.com/virtual-kubelet/virtual-kubelet/test/util"
)

const (
	// defaultEventRecorderBufferSize is the default buffer size to use when creating fake event recorders.
	defaultEventRecorderBufferSize = 5
	// envVarName1 is a string that can be used as the name of an environment value.
	envVarName1 = "FOO"
	// envVarValue1 is a string meant to be used as the value of the "envVarName1" environment value.
	envVarValue1 = "foo_value"
	// envVarName2 is a string that can be used as the name of an environment value.
	envVarName2 = "BAR"
	// envVarName3 is a string that can be used as the name of an environment value.
	envVarName3 = "CHO"
	// envVarName4 is a string that can be used as the name of an environment value.
	envVarName4 = "CAR"
	// invalidKey1 is a key that cannot be used as the name of an environment variable (since it starts with a digit).
	invalidKey1 = "1INVALID"
	// invalidKey2 is a key that cannot be used as the name of an environment variable (since it starts with a digit).
	invalidKey2 = "2INVALID"
	// invalidKey3 is a key that cannot be used as the name of an environment variable (since it starts with a digit).
	invalidKey3 = "3INVALID"
	// keyFoo is a key that can be used as the name of an environment variable.
	keyFoo = "FOO"
	// keyBar is a key that can be used as the name of an environment variable.
	keyBar = "BAR"
	// keyBaz is a key that can be used as the name of an environment variable.
	keyBaz = "BAZ"
	// namespace is the namespace to which mock resources used in the tests belong.
	namespace = "foo"
	// prefixConfigMap1 is the prefix used in ".envFrom" fields that reference "config-map-1".
	prefixConfigMap1 = "FROM_CONFIGMAP_1_"
	// prefixConfigMap2 is the prefix used in ".envFrom" fields that reference "config-map-2".
	prefixConfigMap2 = "FROM_CONFIGMAP_2_"
	// prefixSecret1 is the prefix used in ".envFrom" fields that reference "secret-1".
	prefixSecret1 = "FROM_SECRET_1_"
	// prefixSecret1 is the prefix used in ".envFrom" fields that reference "secret-1".
	prefixSecret2 = "FROM_SECRET_2_"
)

var (
	// bFalse represents the "false" value.
	// Used so we can take its address when a pointer to a bool is required.
	bFalse = false
	// bFalse represents the "true" value.
	// Used so we can take its address when a pointer to a bool is required.
	bTrue = true
	// configMap1 is a configmap containing a single key, valid as the name of an environment variable.
	configMap1 = testutil.FakeConfigMap(namespace, "configmap-1", map[string]string{
		keyFoo: "__foo__",
	})
	// configMap2 is a configmap containing a single key, valid as the name of an environment variable.
	configMap2 = testutil.FakeConfigMap(namespace, "configmap-2", map[string]string{
		keyBar: "__bar__",
	})
	// configMap3 is a configmap containing a single key, valid as the name of an environment variable.
	configMap3 = testutil.FakeConfigMap(namespace, "configmap-2", map[string]string{
		keyFoo: "__foo__",
		keyBar: "__bar__",
	})
	// invalidConfigMap1 is a configmap containing two keys, one of which is invalid as the name of an environment variable.
	invalidConfigMap1 = testutil.FakeConfigMap(namespace, "invalid-configmap-1", map[string]string{
		keyFoo:      "__foo__",
		invalidKey1: "will-be-skipped",
		invalidKey2: "will-be-skipped",
	})
	// secret1 is a secret containing a single key, valid as the name of an environment variable.
	secret1 = testutil.FakeSecret(namespace, "secret-1", map[string]string{
		keyBaz: "__baz__",
	})
	// secret2 is a secret containing a single key, valid as the name of an environment variable.
	secret2 = testutil.FakeSecret(namespace, "secret-2", map[string]string{
		keyFoo: "__foo__",
	})
	// invalidSecret1 is a secret containing two keys, one of which is invalid as the name for an environment variable.
	invalidSecret1 = testutil.FakeSecret(namespace, "invalid-secret-1", map[string]string{
		invalidKey3: "will-be-skipped",
		keyBaz:      "__baz__",
	})
)

// TestPopulatePodWithInitContainersUsingEnv populates the environment of a pod with four containers (two init containers, two containers) using ".env".
// Then, it checks that the resulting environment for each container contains the expected environment variables.
func TestPopulatePodWithInitContainersUsingEnv(t *testing.T) {
	rm := testutil.FakeResourceManager(configMap1, configMap2, secret1, secret2)
	er := testutil.FakeEventRecorder(defaultEventRecorderBufferSize)

	// Create a pod object having two init containers and two containers.
	// The containers' environment is to be populated both from directly-provided values and from keys in two configmaps and two secrets.
	pod := &corev1.Pod{
		ObjectMeta: metav1.ObjectMeta{
			Namespace: namespace,
			Name:      "pod-0",
		},
		Spec: corev1.PodSpec{
			InitContainers: []corev1.Container{
				{
					Env: []corev1.EnvVar{
						{
							Name:  envVarName1,
							Value: envVarValue1,
						},
						{
							Name: envVarName2,
							ValueFrom: &corev1.EnvVarSource{
								ConfigMapKeyRef: &corev1.ConfigMapKeySelector{
									LocalObjectReference: corev1.LocalObjectReference{
										Name: configMap1.Name,
									},
									Key: keyFoo,
									// This scenario has been observed before https://github.com/virtual-kubelet/virtual-kubelet/issues/444#issuecomment-449611851.
									Optional: nil,
								},
							},
						},
					},
				},
				{
					Env: []corev1.EnvVar{
						{
							Name:  envVarName1,
							Value: envVarValue1,
						},
						{
							Name: envVarName2,
							ValueFrom: &corev1.EnvVarSource{
								SecretKeyRef: &corev1.SecretKeySelector{
									LocalObjectReference: corev1.LocalObjectReference{
										Name: secret1.Name,
									},
									Key:      keyBaz,
									Optional: &bFalse,
								},
							},
						},
					},
				},
			},
			Containers: []corev1.Container{
				{
					Env: []corev1.EnvVar{
						{
							Name:  envVarName1,
							Value: envVarValue1,
						},
						{
							Name: envVarName2,
							ValueFrom: &corev1.EnvVarSource{
								ConfigMapKeyRef: &corev1.ConfigMapKeySelector{
									LocalObjectReference: corev1.LocalObjectReference{
										Name: configMap1.Name,
									},
									Key: keyFoo,
									// This scenario has been observed before https://github.com/virtual-kubelet/virtual-kubelet/issues/444#issuecomment-449611851.
									Optional: nil,
								},
							},
						},
					},
				},
				{
					Env: []corev1.EnvVar{
						{
							Name:  envVarName1,
							Value: envVarValue1,
						},
						{
							Name: envVarName2,
							ValueFrom: &corev1.EnvVarSource{
								SecretKeyRef: &corev1.SecretKeySelector{
									LocalObjectReference: corev1.LocalObjectReference{
										Name: secret1.Name,
									},
									Key:      keyBaz,
									Optional: &bFalse,
								},
							},
						},
					},
				},
			},
			EnableServiceLinks: &bFalse,
		},
	}

	// Populate the pod's environment.
	err := populateEnvironmentVariables(context.Background(), pod, rm, er)
	assert.Check(t, err)

	// Make sure that all the containers' environments contain all the expected keys and values.
	assert.Check(t, is.DeepEqual(pod.Spec.InitContainers[0].Env, []corev1.EnvVar{
		{
			Name:  envVarName1,
			Value: envVarValue1,
		},
		{
			Name:  envVarName2,
			Value: configMap1.Data[keyFoo],
		},
	}, sortOpt))
	assert.Check(t, is.DeepEqual(pod.Spec.InitContainers[1].Env, []corev1.EnvVar{
		{
			Name:  envVarName1,
			Value: envVarValue1,
		},
		{
			Name:  envVarName2,
			Value: string(secret1.Data[keyBaz]),
		},
	}, sortOpt))
	assert.Check(t, is.DeepEqual(pod.Spec.Containers[0].Env, []corev1.EnvVar{
		{
			Name:  envVarName1,
			Value: envVarValue1,
		},
		{
			Name:  envVarName2,
			Value: configMap1.Data[keyFoo],
		},
	}, sortOpt))
	assert.Check(t, is.DeepEqual(pod.Spec.Containers[1].Env, []corev1.EnvVar{
		{
			Name:  envVarName1,
			Value: envVarValue1,
		},
		{
			Name:  envVarName2,
			Value: string(secret1.Data[keyBaz]),
		},
	}, sortOpt))
}

// TestPopulatePodWithInitContainersUsingEnv populates the environment of a pod with four containers (two init containers, two containers) using ".env".
// Then, it checks that the resulting environment for each container contains the expected environment variables.
func TestPopulatePodWithInitContainersUsingEnvWithFieldRef(t *testing.T) {
	rm := testutil.FakeResourceManager(configMap1, configMap2, secret1, secret2)
	er := testutil.FakeEventRecorder(defaultEventRecorderBufferSize)

	// Create a pod object having two init containers and two containers.
	// The containers' environment is to be populated both from directly-provided values and from keys in two configmaps and two secrets.
	pod := &corev1.Pod{
		ObjectMeta: metav1.ObjectMeta{
			Namespace: namespace,
			Name:      "pod-0",
			Labels: map[string]string{
				"zone":    "us-est-coast",
				"cluster": "test-cluster1",
				"rack":    "rack-22",
			},
			Annotations: map[string]string{
				"build":   "two",
				"builder": "john-doe",
			},
		},
		Spec: corev1.PodSpec{
			NodeName:           "namenode",
			ServiceAccountName: "serviceaccount",
			InitContainers: []corev1.Container{
				{
					Env: []corev1.EnvVar{
						{
							Name: envVarName1,
							ValueFrom: &corev1.EnvVarSource{
								FieldRef: &corev1.ObjectFieldSelector{
									APIVersion: "v1",
									FieldPath:  "spec.nodeName",
								},
							},
						},
						{
							Name: envVarName2,
							ValueFrom: &corev1.EnvVarSource{
								FieldRef: &corev1.ObjectFieldSelector{
									APIVersion: "v1",
									FieldPath:  "metadata.labels",
								},
							},
						},
						{
							Name: envVarName3,
							ValueFrom: &corev1.EnvVarSource{
								FieldRef: &corev1.ObjectFieldSelector{
									APIVersion: "v1",
									FieldPath:  "metadata.annotations",
								},
							},
						},
						{
							Name: envVarName4,
							ValueFrom: &corev1.EnvVarSource{
								FieldRef: &corev1.ObjectFieldSelector{
									APIVersion: "v1",
									FieldPath:  "spec.serviceAccountName",
								},
							},
						},
					},
				},
			},
			Containers: []corev1.Container{
				{
					Env: []corev1.EnvVar{
						{
							Name: envVarName1,
							ValueFrom: &corev1.EnvVarSource{
								FieldRef: &corev1.ObjectFieldSelector{
									APIVersion: "v1",
									FieldPath:  "spec.nodeName",
								},
							},
						},
						{
							Name: envVarName2,
							ValueFrom: &corev1.EnvVarSource{
								FieldRef: &corev1.ObjectFieldSelector{
									APIVersion: "v1",
									FieldPath:  "metadata.labels",
								},
							},
						},
						{
							Name: envVarName3,
							ValueFrom: &corev1.EnvVarSource{
								FieldRef: &corev1.ObjectFieldSelector{
									APIVersion: "v1",
									FieldPath:  "metadata.annotations",
								},
							},
						},
						{
							Name: envVarName4,
							ValueFrom: &corev1.EnvVarSource{
								FieldRef: &corev1.ObjectFieldSelector{
									APIVersion: "v1",
									FieldPath:  "spec.serviceAccountName",
								},
							},
						},
					},
				},
			},
			EnableServiceLinks: &bFalse,
		},
	}

	// Populate the pod's environment.
	err := populateEnvironmentVariables(context.Background(), pod, rm, er)
	assert.NilError(t, err)

	// Make sure that all the containers' environments contain all the expected keys and values.
	assert.Check(t, is.DeepEqual(pod.Spec.InitContainers[0].Env, []corev1.EnvVar{

		{
			Name:  envVarName1,
			Value: "namenode",
		},
		{
			Name:  envVarName2,
			Value: "cluster=\"test-cluster1\"\nrack=\"rack-22\"\nzone=\"us-est-coast\"",
		},
		{
			Name:  envVarName3,
			Value: "build=\"two\"\nbuilder=\"john-doe\"",
		},
		{
			Name:  envVarName4,
			Value: "serviceaccount",
		},
	}, sortOpt))

	assert.Check(t, is.DeepEqual(pod.Spec.Containers[0].Env, []corev1.EnvVar{

		{
			Name:  envVarName1,
			Value: "namenode",
		},
		{
			Name:  envVarName2,
			Value: "cluster=\"test-cluster1\"\nrack=\"rack-22\"\nzone=\"us-est-coast\"",
		},
		{
			Name:  envVarName3,
			Value: "build=\"two\"\nbuilder=\"john-doe\"",
		},
		{
			Name:  envVarName4,
			Value: "serviceaccount",
		},
	}, sortOpt))
}

// TestPopulatePodWithInitContainersUsingEnvFrom populates the environment of a pod with four containers (two init containers, two containers) using ".envFrom".
// Then, it checks that the resulting environment for each container contains the expected environment variables.
func TestPopulatePodWithInitContainersUsingEnvFrom(t *testing.T) {
	rm := testutil.FakeResourceManager(configMap1, configMap2, secret1, secret2)
	er := testutil.FakeEventRecorder(defaultEventRecorderBufferSize)

	// Create a pod object having two init containers and two containers.
	// The containers' environment is to be populated from two configmaps and two secrets.
	pod := &corev1.Pod{
		ObjectMeta: metav1.ObjectMeta{
			Namespace: namespace,
			Name:      "pod-0",
		},
		Spec: corev1.PodSpec{
			InitContainers: []corev1.Container{
				{
					EnvFrom: []corev1.EnvFromSource{
						{
							Prefix: prefixConfigMap1,
							ConfigMapRef: &corev1.ConfigMapEnvSource{
								LocalObjectReference: corev1.LocalObjectReference{
									Name: configMap1.Name,
								},
							},
						},
					},
				},
				{
					EnvFrom: []corev1.EnvFromSource{
						{
							Prefix: prefixConfigMap2,
							ConfigMapRef: &corev1.ConfigMapEnvSource{
								LocalObjectReference: corev1.LocalObjectReference{
									Name: configMap2.Name,
								},
							},
						},
					},
				},
			},
			Containers: []corev1.Container{
				{
					EnvFrom: []corev1.EnvFromSource{
						{
							Prefix: prefixSecret1,
							SecretRef: &corev1.SecretEnvSource{
								LocalObjectReference: corev1.LocalObjectReference{
									Name: secret1.Name,
								},
							},
						},
					},
				},
				{
					EnvFrom: []corev1.EnvFromSource{
						{
							Prefix: prefixSecret2,
							SecretRef: &corev1.SecretEnvSource{
								LocalObjectReference: corev1.LocalObjectReference{
									Name: secret2.Name,
								},
							},
						},
					},
				},
			},
			EnableServiceLinks: &bFalse,
		},
	}

	// Populate the pod's environment.
	err := populateEnvironmentVariables(context.Background(), pod, rm, er)
	assert.Check(t, err)

	// Make sure that all the containers' environments contain all the expected keys and values.
	assert.Check(t, is.DeepEqual(pod.Spec.InitContainers[0].Env, []corev1.EnvVar{
		{
			Name:  prefixConfigMap1 + keyFoo,
			Value: configMap1.Data[keyFoo],
		},
	}, sortOpt))
	assert.Check(t, is.DeepEqual(pod.Spec.InitContainers[1].Env, []corev1.EnvVar{
		{
			Name:  prefixConfigMap2 + keyBar,
			Value: configMap2.Data[keyBar],
		},
	}, sortOpt))
	assert.Check(t, is.DeepEqual(pod.Spec.Containers[0].Env, []corev1.EnvVar{
		{
			Name:  prefixSecret1 + keyBaz,
			Value: string(secret1.Data[keyBaz]),
		},
	}, sortOpt))
	assert.Check(t, is.DeepEqual(pod.Spec.Containers[1].Env, []corev1.EnvVar{
		{
			Name:  prefixSecret2 + keyFoo,
			Value: string(secret2.Data[keyFoo]),
		},
	}, sortOpt))
}

// TestEnvFromTwoConfigMapsAndOneSecret populates the environment of a container from two configmaps and one secret.
// Then, it checks that the resulting environment contains all the expected environment variables and values.
func TestEnvFromTwoConfigMapsAndOneSecret(t *testing.T) {
	rm := testutil.FakeResourceManager(configMap1, configMap2, secret1)
	er := testutil.FakeEventRecorder(defaultEventRecorderBufferSize)

	// Create a pod object having a single container.
	// The container's environment is to be populated from two configmaps and one secret.
	pod := &corev1.Pod{
		ObjectMeta: metav1.ObjectMeta{
			Namespace: namespace,
			Name:      "pod-0",
		},
		Spec: corev1.PodSpec{
			Containers: []corev1.Container{
				{
					EnvFrom: []corev1.EnvFromSource{
						{
							Prefix: prefixConfigMap1,
							ConfigMapRef: &corev1.ConfigMapEnvSource{
								LocalObjectReference: corev1.LocalObjectReference{
									Name: configMap1.Name,
								},
							},
						},
						{
							Prefix: prefixConfigMap2,
							ConfigMapRef: &corev1.ConfigMapEnvSource{
								LocalObjectReference: corev1.LocalObjectReference{
									Name: configMap2.Name,
								},
							},
						},
						{
							Prefix: prefixSecret1,
							SecretRef: &corev1.SecretEnvSource{
								LocalObjectReference: corev1.LocalObjectReference{
									Name: secret1.Name,
								},
							},
						},
					},
				},
			},
			EnableServiceLinks: &bFalse,
		},
	}

	// Populate the container's environment.
	err := populateContainerEnvironment(context.Background(), pod, &pod.Spec.Containers[0], rm, er)
	assert.Check(t, err)

	// Make sure that the container's environment contains all the expected keys and values.
	assert.Check(t, is.DeepEqual(pod.Spec.Containers[0].Env, []corev1.EnvVar{
		{
			Name:  prefixConfigMap1 + keyFoo,
			Value: configMap1.Data[keyFoo],
		},
		{
			Name:  prefixConfigMap2 + keyBar,
			Value: configMap2.Data[keyBar],
		},
		{
			Name:  prefixSecret1 + keyBaz,
			Value: string(secret1.Data[keyBaz]),
		},
	}, sortOpt))

	// Make sure that no events have been recorded, as the configmaps and secrets are valid.
	assert.Check(t, is.Len(er.Events, 0))
}

// TestEnvFromConfigMapAndSecretWithInvalidKeys populates the environment of a container from a configmap and a secret containing invalid keys.
// Then, it checks that the resulting environment contains all the expected environment variables and values, and that the invalid keys have been skipped.
func TestEnvFromConfigMapAndSecretWithInvalidKeys(t *testing.T) {
	rm := testutil.FakeResourceManager(invalidConfigMap1, invalidSecret1)
	er := testutil.FakeEventRecorder(defaultEventRecorderBufferSize)

	// Create a pod object having a single container.
	// The container's environment is to be populated from a configmap and a secret, both of which have some invalid keys.
	pod := &corev1.Pod{
		ObjectMeta: metav1.ObjectMeta{
			Namespace: namespace,
			Name:      "pod-0",
		},
		Spec: corev1.PodSpec{
			Containers: []corev1.Container{
				{
					EnvFrom: []corev1.EnvFromSource{
						{
							ConfigMapRef: &corev1.ConfigMapEnvSource{
								LocalObjectReference: corev1.LocalObjectReference{
									Name: invalidConfigMap1.Name,
								},
							},
						},
						{
							SecretRef: &corev1.SecretEnvSource{
								LocalObjectReference: corev1.LocalObjectReference{
									Name: invalidSecret1.Name,
								},
							},
						},
					},
				},
			},
			EnableServiceLinks: &bFalse,
		},
	}

	// Populate the pods's environment.
	err := populateEnvironmentVariables(context.Background(), pod, rm, er)
	assert.Check(t, err)

	// Make sure that the container's environment has two variables (corresponding to the single valid key in both the configmap and the secret).
	assert.Check(t, is.DeepEqual(pod.Spec.Containers[0].Env, []corev1.EnvVar{
		{
			Name:  keyFoo,
			Value: invalidConfigMap1.Data[keyFoo],
		},
		{
			Name:  keyBaz,
			Value: string(invalidSecret1.Data[keyBaz]),
		},
	}, sortOpt))

	// Make sure that two events have been received (one for the configmap and one for the secret).
	assert.Check(t, is.Len(er.Events, 2))

	// Grab the first event (which should correspond to the configmap) and make sure it has the correct reason and message.
	event1 := <-er.Events
	assert.Check(t, is.Contains(event1, ReasonInvalidEnvironmentVariableNames))
	assert.Check(t, is.Contains(event1, invalidKey1))
	assert.Check(t, is.Contains(event1, invalidKey2))

	// Grab the second event (which should correspond to the secret) and make sure it has the correct reason and message.
	event2 := <-er.Events
	assert.Check(t, is.Contains(event2, ReasonInvalidEnvironmentVariableNames))
	assert.Check(t, is.Contains(event2, invalidKey3))
}

// TestEnvOverridesEnvFrom populates the environment of a container from a configmap, and from another configmap's key with a "conflicting" key.
// Then, it checks that the value of the "conflicting" key has been correctly overriden.
func TestEnvOverridesEnvFrom(t *testing.T) {
	rm := testutil.FakeResourceManager(configMap3)
	er := testutil.FakeEventRecorder(defaultEventRecorderBufferSize)

	// override will override the value of "keyFoo" from "configMap3".
	override := "__override__"

	// Create a pod object having a single container.
	// The container's environment is to be populated from a configmap, and later overriden with a value provided directly.
	pod := &corev1.Pod{
		ObjectMeta: metav1.ObjectMeta{
			Namespace: namespace,
			Name:      "pod-0",
		},
		Spec: corev1.PodSpec{
			Containers: []corev1.Container{
				{
					EnvFrom: []corev1.EnvFromSource{
						{
							ConfigMapRef: &corev1.ConfigMapEnvSource{
								LocalObjectReference: corev1.LocalObjectReference{
									Name: configMap3.Name,
								},
							},
						},
					},
					Env: []corev1.EnvVar{
						{
							Name:  keyFoo, // One of the keys in configMap3.
							Value: override,
						},
					},
				},
			},
			EnableServiceLinks: &bFalse,
		},
	}

	// Populate the pods's environment.
	err := populateEnvironmentVariables(context.Background(), pod, rm, er)
	assert.Check(t, err)

	// Make sure that the container's environment contains all the expected keys and values.
	assert.Check(t, is.DeepEqual(pod.Spec.Containers[0].Env, []corev1.EnvVar{
		{
			Name:  keyFoo,
			Value: override,
		},
		{
			Name:  keyBar,
			Value: configMap3.Data[keyBar],
		},
	},
		sortOpt,
	))

	// Make sure that no events have been recorded, as the configmaps and secrets are valid.
	assert.Check(t, is.Len(er.Events, 0))
}

var sortOpt gocmp.Option = gocmp.Transformer("Sort", sortEnv)

func sortEnv(in []corev1.EnvVar) []corev1.EnvVar {
	out := append([]corev1.EnvVar(nil), in...)
	sort.Slice(out, func(i, j int) bool {
		return out[i].Name < out[j].Name
	})
	return out
}

// TestEnvFromInexistentConfigMaps populates the environment of a container from two configmaps (one of them optional) that do not exist.
// Then, it checks that the expected events have been recorded.
func TestEnvFromInexistentConfigMaps(t *testing.T) {
	rm := testutil.FakeResourceManager()
	er := testutil.FakeEventRecorder(defaultEventRecorderBufferSize)

	missingConfigMap1Name := "missing-config-map-1"
	missingConfigMap2Name := "missing-config-map-2"

	// Create a pod object having a single container.
	// The container's environment is to be populated from two configmaps that do not exist.
	pod := &corev1.Pod{
		ObjectMeta: metav1.ObjectMeta{
			Namespace: namespace,
			Name:      "pod-0",
		},
		Spec: corev1.PodSpec{
			Containers: []corev1.Container{
				{
					EnvFrom: []corev1.EnvFromSource{
						{
							ConfigMapRef: &corev1.ConfigMapEnvSource{
								LocalObjectReference: corev1.LocalObjectReference{
									Name: missingConfigMap1Name,
								},
								// The configmap reference is optional.
								Optional: &bTrue,
							},
						},
						{
							ConfigMapRef: &corev1.ConfigMapEnvSource{
								LocalObjectReference: corev1.LocalObjectReference{
									Name: missingConfigMap2Name,
								},
								// The configmap reference is mandatory.
								Optional: &bFalse,
							},
						},
					},
				},
			},
			EnableServiceLinks: &bFalse,
		},
	}

	// Populate the pods's environment.
	err := populateEnvironmentVariables(context.Background(), pod, rm, er)
	assert.Check(t, is.ErrorContains(err, ""))

	// Make sure that two events have been recorded with the correct reason and message.
	assert.Check(t, is.Len(er.Events, 2))
	event1 := <-er.Events
	assert.Check(t, is.Contains(event1, ReasonOptionalConfigMapNotFound))
	assert.Check(t, is.Contains(event1, missingConfigMap1Name))
	event2 := <-er.Events
	assert.Check(t, is.Contains(event2, ReasonMandatoryConfigMapNotFound))
	assert.Check(t, is.Contains(event2, missingConfigMap2Name))
}

func TestEnvFromInexistentSecrets(t *testing.T) {
	rm := testutil.FakeResourceManager()
	er := testutil.FakeEventRecorder(defaultEventRecorderBufferSize)

	missingSecret1Name := "missing-secret-1"
	missingSecret2Name := "missing-secret-2"

	// Create a pod object having a single container.
	// The container's environment is to be populated from two secrets that do not exist.
	pod := &corev1.Pod{
		ObjectMeta: metav1.ObjectMeta{
			Namespace: namespace,
			Name:      "pod-0",
		},
		Spec: corev1.PodSpec{
			Containers: []corev1.Container{
				{
					EnvFrom: []corev1.EnvFromSource{
						{
							SecretRef: &corev1.SecretEnvSource{
								LocalObjectReference: corev1.LocalObjectReference{
									Name: missingSecret1Name,
								},
								// The secret reference is optional.
								Optional: &bTrue,
							},
						},
						{
							SecretRef: &corev1.SecretEnvSource{
								LocalObjectReference: corev1.LocalObjectReference{
									Name: missingSecret2Name,
								},
								// The secret reference is mandatory.
								Optional: &bFalse,
							},
						},
					},
				},
			},
			EnableServiceLinks: &bFalse,
		},
	}

	// Populate the pods's environment.
	err := populateEnvironmentVariables(context.Background(), pod, rm, er)
	assert.Check(t, is.ErrorContains(err, ""))

	// Make sure that two events have been recorded with the correct reason and message.
	assert.Check(t, is.Len(er.Events, 2))
	event1 := <-er.Events
	assert.Check(t, is.Contains(event1, ReasonOptionalSecretNotFound))
	assert.Check(t, is.Contains(event1, missingSecret1Name))
	event2 := <-er.Events
	assert.Check(t, is.Contains(event2, ReasonMandatorySecretNotFound))
	assert.Check(t, is.Contains(event2, missingSecret2Name))
}

// TestEnvReferencingInexistentConfigMapKey tries populates the environment of a container using a keys from a configmaps that does not exist.
// Then, it checks that the expected event has been recorded.
func TestEnvReferencingInexistentConfigMapKey(t *testing.T) {
	rm := testutil.FakeResourceManager()
	er := testutil.FakeEventRecorder(defaultEventRecorderBufferSize)

	missingConfigMapName := "missing-config-map"

	// Create a pod object having a single container and referencing a key from a configmap that does not exist.
	pod := &corev1.Pod{
		ObjectMeta: metav1.ObjectMeta{
			Namespace: namespace,
			Name:      "pod-0",
		},
		Spec: corev1.PodSpec{
			Containers: []corev1.Container{
				{
					Env: []corev1.EnvVar{
						{
							Name: "envvar",
							ValueFrom: &corev1.EnvVarSource{
								ConfigMapKeyRef: &corev1.ConfigMapKeySelector{
									LocalObjectReference: corev1.LocalObjectReference{
										Name: missingConfigMapName,
									},
									Key: "key",
									// This scenario has been observed before https://github.com/virtual-kubelet/virtual-kubelet/issues/444#issuecomment-449611851.
									// A nil value of optional means "mandatory", hence we should expect "populateEnvironmentVariables" to return an error.
									Optional: nil,
								},
							},
						},
					},
				},
			},
			EnableServiceLinks: &bFalse,
		},
	}

	// Populate the pods's environment.
	err := populateEnvironmentVariables(context.Background(), pod, rm, er)
	assert.Check(t, is.ErrorContains(err, ""))

	// Make sure that two events have been recorded with the correct reason and message.
	assert.Check(t, is.Len(er.Events, 1))
	event1 := <-er.Events
	assert.Check(t, is.Contains(event1, ReasonMandatoryConfigMapNotFound))
	assert.Check(t, is.Contains(event1, missingConfigMapName))
}

// TestEnvReferencingInexistentSecretKey tries populates the environment of a container using a keys from a secret that does not exist.
// Then, it checks that the expected event has been recorded.
func TestEnvReferencingInexistentSecretKey(t *testing.T) {
	rm := testutil.FakeResourceManager()
	er := testutil.FakeEventRecorder(defaultEventRecorderBufferSize)

	missingSecretName := "missing-secret"

	// Create a pod object having a single container and referencing a key from a secret that does not exist.
	pod := &corev1.Pod{
		ObjectMeta: metav1.ObjectMeta{
			Namespace: namespace,
			Name:      "pod-0",
		},
		Spec: corev1.PodSpec{
			Containers: []corev1.Container{
				{
					Env: []corev1.EnvVar{
						{
							Name: "envvar",
							ValueFrom: &corev1.EnvVarSource{
								SecretKeyRef: &corev1.SecretKeySelector{
									LocalObjectReference: corev1.LocalObjectReference{
										Name: missingSecretName,
									},
									Key: "key",
									// This scenario has been observed before https://github.com/virtual-kubelet/virtual-kubelet/issues/444#issuecomment-449611851.
									// A nil value of optional means "mandatory", hence we should expect "populateEnvironmentVariables" to return an error.
									Optional: nil,
								},
							},
						},
					},
				},
			},
			EnableServiceLinks: &bFalse,
		},
	}

	// Populate the pods's environment.
	err := populateEnvironmentVariables(context.Background(), pod, rm, er)
	assert.Check(t, is.ErrorContains(err, ""))

	// Make sure that two events have been recorded with the correct reason and message.
	assert.Check(t, is.Len(er.Events, 1))
	event1 := <-er.Events
	assert.Check(t, is.Contains(event1, ReasonMandatorySecretNotFound))
	assert.Check(t, is.Contains(event1, missingSecretName))
}

// TestServiceEnvVar tries to populate the environment of a container using services with ServiceLinks enabled and disabled.
func TestServiceEnvVar(t *testing.T) {
	namespace2 := "namespace-02"

	service1 := testutil.FakeService(metav1.NamespaceDefault, "kubernetes", "1.2.3.1", "TCP", 8081)
	service2 := testutil.FakeService(namespace, "test", "1.2.3.3", "TCP", 8083)
	// unused svc to show it isn't populated within a different namespace.
	service3 := testutil.FakeService(namespace2, "unused", "1.2.3.4", "TCP", 8084)

	rm := testutil.FakeResourceManager(service1, service2, service3)
	er := testutil.FakeEventRecorder(defaultEventRecorderBufferSize)

	pod := &corev1.Pod{
		ObjectMeta: metav1.ObjectMeta{
			Namespace: namespace,
			Name:      "test-pod-name",
		},
		Spec: corev1.PodSpec{
			Containers: []corev1.Container{
				{
					Env: []corev1.EnvVar{
						{Name: envVarName1, Value: envVarValue1},
					},
				},
			},
		},
	}

	testCases := []struct {
		name               string          // the name of the test case
		enableServiceLinks *bool           // enabling service links
		expectedEnvs       []corev1.EnvVar // a set of expected environment vars
	}{
		{
			name:               "ServiceLinks disabled",
			enableServiceLinks: &bFalse,
			expectedEnvs: []corev1.EnvVar{
				{Name: envVarName1, Value: envVarValue1},
				{Name: "KUBERNETES_SERVICE_PORT", Value: "8081"},
				{Name: "KUBERNETES_SERVICE_HOST", Value: "1.2.3.1"},
				{Name: "KUBERNETES_PORT", Value: "tcp://1.2.3.1:8081"},
				{Name: "KUBERNETES_PORT_8081_TCP", Value: "tcp://1.2.3.1:8081"},
				{Name: "KUBERNETES_PORT_8081_TCP_PROTO", Value: "tcp"},
				{Name: "KUBERNETES_PORT_8081_TCP_PORT", Value: "8081"},
				{Name: "KUBERNETES_PORT_8081_TCP_ADDR", Value: "1.2.3.1"},
			},
		},
		{
			name:               "ServiceLinks enabled",
			enableServiceLinks: &bTrue,
			expectedEnvs: []corev1.EnvVar{
				{Name: envVarName1, Value: envVarValue1},
				{Name: "TEST_SERVICE_HOST", Value: "1.2.3.3"},
				{Name: "TEST_SERVICE_PORT", Value: "8083"},
				{Name: "TEST_PORT", Value: "tcp://1.2.3.3:8083"},
				{Name: "TEST_PORT_8083_TCP", Value: "tcp://1.2.3.3:8083"},
				{Name: "TEST_PORT_8083_TCP_PROTO", Value: "tcp"},
				{Name: "TEST_PORT_8083_TCP_PORT", Value: "8083"},
				{Name: "TEST_PORT_8083_TCP_ADDR", Value: "1.2.3.3"},
				{Name: "KUBERNETES_SERVICE_PORT", Value: "8081"},
				{Name: "KUBERNETES_SERVICE_HOST", Value: "1.2.3.1"},
				{Name: "KUBERNETES_PORT", Value: "tcp://1.2.3.1:8081"},
				{Name: "KUBERNETES_PORT_8081_TCP", Value: "tcp://1.2.3.1:8081"},
				{Name: "KUBERNETES_PORT_8081_TCP_PROTO", Value: "tcp"},
				{Name: "KUBERNETES_PORT_8081_TCP_PORT", Value: "8081"},
				{Name: "KUBERNETES_PORT_8081_TCP_ADDR", Value: "1.2.3.1"},
			},
		},
	}

	for _, tc := range testCases {
		pod.Spec.EnableServiceLinks = tc.enableServiceLinks

		err := populateEnvironmentVariables(context.Background(), pod, rm, er)
		assert.NilError(t, err, "[%s]", tc.name)
		assert.Check(t, is.DeepEqual(pod.Spec.Containers[0].Env, tc.expectedEnvs, sortOpt))
	}

}