Refactor: use az account show for tenant ID and subscription ID; move kubeconfig/k8s helpers to shared packages

cli/internal/aks/deploy/cilium.go

@@ -3,14 +3,12 @@ package deploy
 import (
 	"context"
 	"errors"
-	"fmt"
 	"log"
-	"net/url"
 	"os"
 	"os/exec"
 
 	"github.com/Azure/aks-flex/plugin/pkg/util/config"
-	"k8s.io/client-go/tools/clientcmd"
+	"github.com/Azure/aks-flex/plugin/pkg/util/k8s"
 )
 
 var ciliumInstallInstruction = errors.New(
@@ -32,7 +30,8 @@ func deployCilium(
 	kubeconfigFile string,
 	cfg *config.Config,
 ) error {
-	k8sServiceHost, k8sServicePort, err := kubeconfigAPIServer(kubeconfigFile)
+	clusterContext := cfg.ClusterName + "-admin"
+	k8sServiceHost, k8sServicePort, err := k8s.APIServerFromKubeconfigFile(kubeconfigFile, clusterContext)
 	if err != nil {
 		return err
 	}
@@ -41,7 +40,7 @@ func deployCilium(
 		ctx,
 		"cilium", "install",
 		"--kubeconfig", kubeconfigFile,
-		"--context", cfg.ClusterName+"-admin",
+		"--context", clusterContext,
 		"--namespace", "kube-system",
 		"--datapath-mode", "aks-byocni",
 		"--helm-set", "aksbyocni.enabled=true",
@@ -58,52 +57,7 @@ func deployCilium(
 		"KUBECONFIG="+kubeconfigFile,
 		"PATH="+os.Getenv("PATH"),
 	)
-	log.Printf("Running: cilium install --kubeconfig %s --context %s --namespace kube-system --datapath-mode aks-byocni --helm-set aksbyocni.enabled=true --helm-set cluster.name=%s --helm-set operator.replicas=1 --helm-set kubeProxyReplacement=true --helm-set k8sServiceHost=%s --helm-set k8sServicePort=%s", kubeconfigFile, cfg.ClusterName+"-admin", cfg.ClusterName, k8sServiceHost, k8sServicePort)
+	log.Printf("Running: cilium install --kubeconfig %s --context %s --namespace kube-system --datapath-mode aks-byocni --helm-set aksbyocni.enabled=true --helm-set cluster.name=%s --helm-set operator.replicas=1 --helm-set kubeProxyReplacement=true --helm-set k8sServiceHost=%s --helm-set k8sServicePort=%s", kubeconfigFile, clusterContext, cfg.ClusterName, k8sServiceHost, k8sServicePort)
 
 	return cmd.Run()
 }
-
-func kubeconfigAPIServer(kubeconfigFile string) (string, string, error) {
-	kcfg, err := clientcmd.LoadFromFile(kubeconfigFile)
-	if err != nil {
-		return "", "", fmt.Errorf("loading kubeconfig for cilium install: %w", err)
-	}
-
-	ctxName := kcfg.CurrentContext
-	if ctxName == "" {
-		return "", "", errors.New("kubeconfig missing current context")
-	}
-
-	ctxCfg, ok := kcfg.Contexts[ctxName]
-	if !ok || ctxCfg == nil {
-		return "", "", fmt.Errorf("kubeconfig missing context %q", ctxName)
-	}
-
-	clusterCfg, ok := kcfg.Clusters[ctxCfg.Cluster]
-	if !ok || clusterCfg == nil {
-		return "", "", fmt.Errorf("kubeconfig missing cluster %q", ctxCfg.Cluster)
-	}
-
-	u, err := url.Parse(clusterCfg.Server)
-	if err != nil {
-		return "", "", fmt.Errorf("parsing API server URL %q: %w", clusterCfg.Server, err)
-	}
-
-	hostname := u.Hostname()
-	port := u.Port()
-	if hostname == "" {
-		return "", "", fmt.Errorf("API server URL missing hostname: %q", clusterCfg.Server)
-	}
-	if port == "" {
-		switch u.Scheme {
-		case "https":
-			port = "443"
-		case "http":
-			port = "80"
-		default:
-			return "", "", fmt.Errorf("API server URL missing port and unsupported scheme %q", u.Scheme)
-		}
-	}
-
-	return hostname, port, nil
-}

cli/internal/aks/deploy/cilium_test.go

@@ -4,6 +4,8 @@ import (
 	"os"
 	"path/filepath"
 	"testing"
+
+	k8sutil "github.com/Azure/aks-flex/plugin/pkg/util/k8s"
 )
 
 func TestKubeconfigAPIServer(t *testing.T) {
@@ -29,9 +31,9 @@ users:
 		t.Fatalf("write kubeconfig: %v", err)
 	}
 
-	host, port, err := kubeconfigAPIServer(kubeconfig)
+	host, port, err := k8sutil.APIServerFromKubeconfigFile(kubeconfig, "")
 	if err != nil {
-		t.Fatalf("kubeconfigAPIServer returned error: %v", err)
+		t.Fatalf("APIServerFromKubeconfigFile returned error: %v", err)
 	}
 	if host != "example.hcp.eastus2.azmk8s.io" {
 		t.Fatalf("unexpected host %q", host)

cli/internal/config/configcmd/defaults.go

@@ -2,10 +2,8 @@ package configcmd
 
 import (
 	"context"
-	"encoding/json"
 	"fmt"
 	"os"
-	"path/filepath"
 
 	"github.com/Azure/azure-sdk-for-go/sdk/azcore/to"
 	"github.com/Azure/azure-sdk-for-go/sdk/azidentity"
@@ -45,7 +43,7 @@ func OrPlaceholder(val string) string {
 // to placeholder values that the user must replace manually.
 func DefaultKubeadmConfig(ctx context.Context) *kubeadm.Config {
 	credOptions := &azidentity.AzureCLICredentialOptions{}
-	if tenantID := azureConfigTenantID(); tenantID != "" {
+	if tenantID := config.AzureTenantID(); tenantID != "" {
 		credOptions.TenantID = tenantID
 	}
 	credentials, err := azidentity.NewAzureCLICredential(credOptions)
@@ -70,37 +68,3 @@ func DefaultKubeadmConfig(ctx context.Context) *kubeadm.Config {
 	}
 	return cfg
 }
-
-func azureConfigTenantID() string {
-	azureConfigDir := os.Getenv("AZURE_CONFIG_DIR")
-	if azureConfigDir == "" {
-		azureConfigDir = filepath.Join(os.Getenv("HOME"), ".azure")
-	}
-
-	b, err := os.ReadFile(filepath.Join(azureConfigDir, "azureProfile.json"))
-	if err != nil {
-		return ""
-	}
-
-	var profile struct {
-		Subscriptions []struct {
-			IsDefault bool   `json:"isDefault"`
-			TenantID  string `json:"tenantId"`
-		} `json:"subscriptions"`
-	}
-	if err := json.Unmarshal(b, &profile); err != nil {
-		return ""
-	}
-
-	for _, sub := range profile.Subscriptions {
-		if sub.IsDefault && sub.TenantID != "" {
-			return sub.TenantID
-		}
-	}
-
-	if len(profile.Subscriptions) == 1 {
-		return profile.Subscriptions[0].TenantID
-	}
-
-	return ""
-}

cli/internal/config/configcmd/defaults_test.go

@@ -1,24 +1 @@
 package configcmd
-
-import (
-	"os"
-	"path/filepath"
-	"testing"
-)
-
-func TestAzureConfigTenantIDUsesAzureConfigDirProfile(t *testing.T) {
-	home := t.TempDir()
-	t.Setenv("HOME", home)
-	azureConfigDir := filepath.Join(t.TempDir(), "azure-profile")
-	if err := os.MkdirAll(azureConfigDir, 0o755); err != nil {
-		t.Fatalf("mkdir azure config dir: %v", err)
-	}
-	if err := os.WriteFile(filepath.Join(azureConfigDir, "azureProfile.json"), []byte(`{"subscriptions":[{"id":"sub","isDefault":true,"tenantId":"tenant-123"}]}`), 0o600); err != nil {
-		t.Fatalf("write azureProfile.json: %v", err)
-	}
-	t.Setenv("AZURE_CONFIG_DIR", azureConfigDir)
-
-	if got := azureConfigTenantID(); got != "tenant-123" {
-		t.Fatalf("unexpected tenant id %q", got)
-	}
-}

plugin/pkg/util/config/config.go

@@ -3,12 +3,10 @@ package config
 import (
 	"fmt"
 	"os"
-	"path/filepath"
+	"os/exec"
 	"regexp"
 	"strconv"
 	"strings"
-
-	"gopkg.in/ini.v1"
 )
 
 var (
@@ -102,27 +100,26 @@ func (c *Config) validate() error {
 	return nil
 }
 
+// AzureTenantID returns the tenant ID of the current Azure CLI account by
+// running `az account show --query 'tenantId' -o tsv`.
+func AzureTenantID() string {
+	out, err := exec.Command("az", "account", "show", "--query", "tenantId", "-o", "tsv").Output()
+	if err != nil {
+		return ""
+	}
+	return strings.TrimSpace(string(out))
+}
+
 func defaultSubscriptionID() string {
 	if subscriptionID := os.Getenv("AZURE_SUBSCRIPTION_ID"); subscriptionID != "" {
 		return subscriptionID
 	}
 
-	azureConfigDir := os.Getenv("AZURE_CONFIG_DIR")
-	if azureConfigDir == "" {
-		azureConfigDir = filepath.Join(os.Getenv("HOME"), ".azure")
-	}
-
-	b, err := os.ReadFile(filepath.Join(azureConfigDir, "clouds.config"))
-	if err != nil {
-		return ""
-	}
-
-	f, err := ini.Load(b)
+	out, err := exec.Command("az", "account", "show", "--query", "id", "-o", "tsv").Output()
 	if err != nil {
 		return ""
 	}
-
-	return f.Section("AzureCloud").Key("subscription").String()
+	return strings.TrimSpace(string(out))
 }
 
 func defaultResourceGroupName() string {

plugin/pkg/util/config/config_test.go

@@ -3,25 +3,42 @@ package config
 import (
 	"os"
 	"path/filepath"
+	"runtime"
 	"testing"
 )
 
-func TestDefaultSubscriptionIDHonorsAzureConfigDir(t *testing.T) {
+func TestDefaultSubscriptionIDUsesAZCLI(t *testing.T) {
+	if runtime.GOOS == "windows" {
+		t.Skip("skipping shell-script fake az on Windows")
+	}
 	t.Setenv("AZURE_SUBSCRIPTION_ID", "")
-	home := t.TempDir()
-	t.Setenv("HOME", home)
 
-	azureConfigDir := filepath.Join(t.TempDir(), "azure-custom")
-	if err := os.MkdirAll(azureConfigDir, 0o755); err != nil {
-		t.Fatalf("mkdir azureConfigDir: %v", err)
-	}
-	if err := os.WriteFile(filepath.Join(azureConfigDir, "clouds.config"), []byte("[AzureCloud]\nsubscription = 11111111-2222-3333-4444-555555555555\n"), 0o600); err != nil {
-		t.Fatalf("write clouds.config: %v", err)
+	dir := t.TempDir()
+	fakeAZ := filepath.Join(dir, "az")
+	if err := os.WriteFile(fakeAZ, []byte("#!/bin/sh\necho '11111111-2222-3333-4444-555555555555'\n"), 0o755); err != nil {
+		t.Fatalf("write fake az: %v", err)
 	}
-	t.Setenv("AZURE_CONFIG_DIR", azureConfigDir)
+	t.Setenv("PATH", dir+string(os.PathListSeparator)+os.Getenv("PATH"))
 
 	got := defaultSubscriptionID()
 	if got != "11111111-2222-3333-4444-555555555555" {
 		t.Fatalf("unexpected subscription id %q", got)
 	}
 }
+
+func TestAzureTenantIDUsesAZCLI(t *testing.T) {
+	if runtime.GOOS == "windows" {
+		t.Skip("skipping shell-script fake az on Windows")
+	}
+
+	dir := t.TempDir()
+	fakeAZ := filepath.Join(dir, "az")
+	if err := os.WriteFile(fakeAZ, []byte("#!/bin/sh\necho 'tenant-from-az'\n"), 0o755); err != nil {
+		t.Fatalf("write fake az: %v", err)
+	}
+	t.Setenv("PATH", dir+string(os.PathListSeparator)+os.Getenv("PATH"))
+
+	if got := AzureTenantID(); got != "tenant-from-az" {
+		t.Fatalf("unexpected tenant id %q", got)
+	}
+}

plugin/pkg/util/k8s/k8s.go

@@ -2,6 +2,9 @@ package k8s
 
 import (
 	"context"
+	"errors"
+	"fmt"
+	"net/url"
 	"os"
 	"path/filepath"
 
@@ -119,3 +122,54 @@ func MergeKubeconfigInto(ctx context.Context, credentials azcore.TokenCredential
 
 	return os.WriteFile(path, content, 0600)
 }
+
+// APIServerFromKubeconfigFile returns the API server hostname and port from
+// the kubeconfig file at path. If contextName is non-empty it is used to
+// select the context; otherwise the file's current-context is used.
+func APIServerFromKubeconfigFile(path, contextName string) (host, port string, err error) {
+	kcfg, err := clientcmd.LoadFromFile(path)
+	if err != nil {
+		return "", "", fmt.Errorf("loading kubeconfig for API server: %w", err)
+	}
+
+	ctxName := contextName
+	if ctxName == "" {
+		ctxName = kcfg.CurrentContext
+	}
+	if ctxName == "" {
+		return "", "", errors.New("kubeconfig missing current context")
+	}
+
+	ctxCfg, ok := kcfg.Contexts[ctxName]
+	if !ok || ctxCfg == nil {
+		return "", "", fmt.Errorf("kubeconfig missing context %q", ctxName)
+	}
+
+	clusterCfg, ok := kcfg.Clusters[ctxCfg.Cluster]
+	if !ok || clusterCfg == nil {
+		return "", "", fmt.Errorf("kubeconfig missing cluster %q", ctxCfg.Cluster)
+	}
+
+	u, err := url.Parse(clusterCfg.Server)
+	if err != nil {
+		return "", "", fmt.Errorf("parsing API server URL %q: %w", clusterCfg.Server, err)
+	}
+
+	hostname := u.Hostname()
+	p := u.Port()
+	if hostname == "" {
+		return "", "", fmt.Errorf("API server URL missing hostname: %q", clusterCfg.Server)
+	}
+	if p == "" {
+		switch u.Scheme {
+		case "https":
+			p = "443"
+		case "http":
+			p = "80"
+		default:
+			return "", "", fmt.Errorf("API server URL missing port and unsupported scheme %q", u.Scheme)
+		}
+	}
+
+	return hostname, p, nil
+}