Add support for outputting kube config credentials from AKS (#953)

* Add kubeconfig to aks resource output

* Added kube config to output variables

* Updated docs

* Fixed naming in docs

* Rebased onto origin master

* Refactored out kubernetes helper

* Made kubeconfig embedded structs private

* Loaded test configs from testdata directory

* Added additional unit tests

* Checking the outputs are set

* Added raw kube config as output

* Changes required for sdkv15

* Parsing the Kube Config as a raw string, since it's decoded via string(bytes)

* Ensuring the Kubernetes Config is set & tested

azurerm/helpers/kubernetes/kube_config.go

@@ -0,0 +1,74 @@
+package kubernetes
+
+import (
+	"fmt"
+
+	yaml "gopkg.in/yaml.v2"
+)
+
+type clusterItem struct {
+	Name    string  `yaml:"name"`
+	Cluster cluster `yaml:"cluster"`
+}
+
+type cluster struct {
+	ClusterAuthorityData string `yaml:"certificate-authority-data"`
+	Server               string `yaml:"server"`
+}
+
+type userItem struct {
+	Name string `yaml:"name"`
+	User user   `yaml:"user"`
+}
+
+type user struct {
+	ClientCertificteData string `yaml:"client-certificate-data"`
+	Token                string `yaml:"token"`
+	ClientKeyData        string `yaml:"client-key-data"`
+}
+
+type contextItem struct {
+	Name    string  `yaml:"name"`
+	Context context `yaml:"context"`
+}
+
+type context struct {
+	Cluster   string `yaml:"cluster"`
+	User      string `yaml:"user"`
+	Namespace string `yaml:"namespace,omitempty"`
+}
+
+type KubeConfig struct {
+	APIVersion     string                 `yaml:"apiVersion"`
+	Clusters       []clusterItem          `yaml:"clusters"`
+	Users          []userItem             `yaml:"users"`
+	Contexts       []contextItem          `yaml:"contexts,omitempty"`
+	CurrentContext string                 `yaml:"current-context,omitempty"`
+	Kind           string                 `yaml:"kind,omitempty"`
+	Preferences    map[string]interface{} `yaml:"preferences,omitempty"`
+}
+
+func ParseKubeConfig(config string) (*KubeConfig, error) {
+	if config == "" {
+		return nil, fmt.Errorf("Cannot parse empty config")
+	}
+
+	var kubeConfig KubeConfig
+	err := yaml.Unmarshal([]byte(config), &kubeConfig)
+	if err != nil {
+		return nil, fmt.Errorf("Failed to unmarshal YAML config with error %+v", err)
+	}
+	if len(kubeConfig.Clusters) <= 0 || len(kubeConfig.Users) <= 0 {
+		return nil, fmt.Errorf("Config %+v contains no valid clusters or users", kubeConfig)
+	}
+	user := kubeConfig.Users[0].User
+	if user.Token == "" && (user.ClientCertificteData == "" || user.ClientKeyData == "") {
+		return nil, fmt.Errorf("Config requires either token or certificate auth for user %+v", user)
+	}
+	cluster := kubeConfig.Clusters[0].Cluster
+	if cluster.Server == "" {
+		return nil, fmt.Errorf("Config has invalid or non existent server for cluster %+v", cluster)
+	}
+
+	return &kubeConfig, nil
+}

azurerm/helpers/kubernetes/kube_config_test.go

@@ -0,0 +1,189 @@
+package kubernetes
+
+import (
+	"fmt"
+	"io/ioutil"
+	"path/filepath"
+	"reflect"
+	"testing"
+)
+
+func TestParseKubeConfig(t *testing.T) {
+	testCases := []struct {
+		sourceFile string
+		expected   KubeConfig
+		checkFunc  func(expected KubeConfig, config string) (bool, error)
+	}{
+		{
+			"user_with_token.yml",
+			KubeConfig{
+				APIVersion: "v1",
+				Clusters: []clusterItem{
+					{
+						Name: "test-cluster",
+						Cluster: cluster{
+							Server: "https://testcluster.net:8080",
+						},
+					},
+				},
+				Users: []userItem{
+					{
+						Name: "test-user",
+						User: user{
+							Token: "test-token",
+						},
+					},
+				},
+				Kind: "Config",
+			},
+			isValidConfig,
+		},
+		{
+			"user_with_cert.yml",
+			KubeConfig{
+				APIVersion: "v1",
+				Clusters: []clusterItem{
+					{
+						Name: "test-cluster",
+						Cluster: cluster{
+							ClusterAuthorityData: "test-cluster-authority-data",
+							Server:               "https://testcluster.org:443",
+						},
+					},
+				},
+				Users: []userItem{
+					{
+						Name: "test-user",
+						User: user{
+							ClientCertificteData: "test-client-certificate-data",
+							ClientKeyData:        "test-client-key-data",
+						},
+					},
+				},
+				Contexts: []contextItem{
+					{
+						Name: "test-cluster",
+						Context: context{
+							Cluster:   "test-cluster",
+							User:      "test-user",
+							Namespace: "test-namespace",
+						},
+					},
+				},
+				CurrentContext: "test-cluster",
+				Kind:           "Config",
+				Preferences:    nil,
+			},
+			isValidConfig,
+		},
+		{
+			"user_with_cert_token.yml",
+			KubeConfig{
+				APIVersion: "v1",
+				Clusters: []clusterItem{
+					{
+						Name: "test-cluster",
+						Cluster: cluster{
+							ClusterAuthorityData: "test-cluster-authority-data",
+							Server:               "https://testcluster.org:443",
+						},
+					},
+				},
+				Users: []userItem{
+					{
+						Name: "test-user",
+						User: user{
+							ClientCertificteData: "test-client-certificate-data",
+							ClientKeyData:        "test-client-key-data",
+							Token:                "test-token",
+						},
+					},
+				},
+				Contexts: []contextItem{
+					{
+						Name: "test-cluster",
+						Context: context{
+							Cluster:   "test-cluster",
+							User:      "test-user",
+							Namespace: "test-namespace",
+						},
+					},
+				},
+				CurrentContext: "test-cluster",
+				Kind:           "Config",
+				Preferences: map[string]interface{}{
+					"colors": true,
+				},
+			},
+			isValidConfig,
+		},
+		{
+			"user_with_no_auth.yml",
+			KubeConfig{},
+			isInvalidConfig,
+		},
+		{
+			"no_cluster.yml",
+			KubeConfig{},
+			isInvalidConfig,
+		},
+		{
+			"no_user.yml",
+			KubeConfig{},
+			isInvalidConfig,
+		},
+		{
+			"user_with_partial_auth.yml",
+			KubeConfig{},
+			isInvalidConfig,
+		},
+		{
+			"cluster_with_no_server.yml",
+			KubeConfig{},
+			isInvalidConfig,
+		},
+	}
+
+	for i, test := range testCases {
+		encodedConfig := LoadConfig(test.sourceFile)
+		if len(encodedConfig) <= 0 {
+			t.Fatalf("Test case [%d]: Failed to read config from file '%+v' \n",
+				i, test.sourceFile)
+		}
+		if success, err := test.checkFunc(test.expected, encodedConfig); !success {
+			t.Fatalf("Test case [%d]: Failed, config '%+v' with error: '%+v'",
+				i, test.sourceFile, err)
+		}
+	}
+}
+
+func isValidConfig(expected KubeConfig, encodedConfig string) (bool, error) {
+	result, err := ParseKubeConfig(encodedConfig)
+	if err != nil {
+		return false, err
+	}
+
+	if !reflect.DeepEqual(expected, *result) {
+		return false, fmt.Errorf("expected '%+v but got '%+v' with encoded config '%+v'",
+			expected, *result, encodedConfig)
+	}
+	return true, nil
+}
+
+func isInvalidConfig(expected KubeConfig, encodedConfig string) (bool, error) {
+	_, err := ParseKubeConfig(encodedConfig)
+	if err == nil {
+		return false, fmt.Errorf("expected test to throw error but didn't")
+	}
+	return true, nil
+}
+
+func LoadConfig(fileName string) string {
+	filePath := filepath.Join("testdata", fileName)
+	bytes, err := ioutil.ReadFile(filePath)
+	if err != nil {
+		return ""
+	}
+
+	return string(bytes)
+}

azurerm/helpers/kubernetes/testdata/cluster_with_no_server.yml

@@ -0,0 +1,9 @@
+apiVersion: v1
+clusters:
+- cluster:
+  name: test-cluster
+users:
+- name: test-user
+  user:
+    token: test-token
+kind: Config

azurerm/helpers/kubernetes/testdata/no_cluster.yml

@@ -0,0 +1,7 @@
+apiVersion: v1
+clusters:
+users:
+- name: test-user
+  user:
+    token: test-token
+kind: Config

azurerm/helpers/kubernetes/testdata/no_user.yml

@@ -0,0 +1,7 @@
+apiVersion: v1
+clusters:
+- cluster:
+    certificate-authority-data: test-cluster-authority-data
+    server: https://testcluster.org:443
+  name: test-cluster
+users:

azurerm/helpers/kubernetes/testdata/user_with_cert.yml

@@ -0,0 +1,19 @@
+apiVersion: v1
+clusters:
+- cluster:
+    certificate-authority-data: test-cluster-authority-data
+    server: https://testcluster.org:443
+  name: test-cluster
+contexts:
+- context:
+    cluster: test-cluster
+    user: test-user
+    namespace: test-namespace
+  name: test-cluster
+current-context: test-cluster
+users:
+- name: test-user
+  user:
+    client-certificate-data: test-client-certificate-data
+    client-key-data: test-client-key-data
+kind: Config

azurerm/helpers/kubernetes/testdata/user_with_cert_token.yml

@@ -0,0 +1,22 @@
+apiVersion: v1
+clusters:
+- cluster:
+    certificate-authority-data: test-cluster-authority-data
+    server: https://testcluster.org:443
+  name: test-cluster
+contexts:
+- context:
+    cluster: test-cluster
+    user: test-user
+    namespace: test-namespace
+  name: test-cluster
+current-context: test-cluster
+users:
+- name: test-user
+  user:
+    client-certificate-data: test-client-certificate-data
+    client-key-data: test-client-key-data
+    token: test-token
+kind: Config
+preferences:
+  colors: true

azurerm/helpers/kubernetes/testdata/user_with_no_auth.yml

@@ -0,0 +1,9 @@
+apiVersion: v1
+clusters:
+- cluster:
+    certificate-authority-data: test-cluster-authority-data
+    server: https://testcluster.org:443
+  name: test-cluster
+users:
+- name: test-user
+  user:

azurerm/helpers/kubernetes/testdata/user_with_partial_auth.yml

@@ -0,0 +1,20 @@
+apiVersion: v1
+clusters:
+- cluster:
+    certificate-authority-data: test-cluster-authority-data
+    server: https://testcluster.org:443
+  name: test-cluster
+contexts:
+- context:
+    cluster: test-cluster
+    user: test-user
+    namespace: test-namespace
+  name: test-cluster
+current-context: test-cluster
+users:
+- name: test-user
+  user:
+    client-certificate-data: test-client-certificate-data
+kind: Config
+preferences:
+  colors: true

azurerm/helpers/kubernetes/testdata/user_with_token.yml

@@ -0,0 +1,10 @@
+apiVersion: v1
+clusters:
+- cluster:
+    server: https://testcluster.net:8080
+  name: test-cluster
+users:
+- name: test-user
+  user:
+    token: test-token
+kind: Config