Improve testing of NewDriver function

Author: dabradley

pkg/azurelustre/azurelustre.go

@@ -53,6 +53,9 @@ const (
 	volumeIDTemplate         = "%s#%s#%s#%s#%s#%s"
 	subnetTemplate           = "/subscriptions/%s/resourceGroups/%s/providers/Microsoft.Network/virtualNetworks/%s/subnets/%s"
 
+	DefaultAzureConfigFileEnv  = "AZURE_CONFIG_FILE"
+	DefaultConfigFilePathLinux = "/etc/kubernetes/azure.json"
+
 	amlFilesystemNameMaxLength = 80
 
 	AgentNotReadyNodeTaintKeySuffix = "/agent-not-ready"
@@ -177,15 +180,21 @@ func NewDriver(options *DriverOptions) *Driver {
 
 	ctx := context.Background()
 
-	// Will need to change if we ever support non-AKS clusters
-	AKSConfigFile := "/etc/kubernetes/azure.json"
-
 	az := &azure.Cloud{}
+
+	credFile, ok := os.LookupEnv(DefaultAzureConfigFileEnv)
+	if ok && strings.TrimSpace(credFile) != "" {
+		klog.V(2).Infof("%s env var set as %v", DefaultAzureConfigFileEnv, credFile)
+	} else {
+		credFile = DefaultConfigFilePathLinux
+		klog.V(2).Infof("use default %s env var: %v", DefaultAzureConfigFileEnv, credFile)
+	}
+
 	config, err := configloader.Load[azure.Config](ctx, nil, &configloader.FileLoaderConfig{
-		FilePath: AKSConfigFile,
+		FilePath: credFile,
 	})
 	if err != nil {
-		klog.V(2).Infof("failed to get cloud config from file %s: %v", AKSConfigFile, err)
+		klog.V(2).Infof("failed to get cloud config from file %s: %v", credFile, err)
 	}
 
 	if config == nil {
@@ -374,6 +383,7 @@ type JSONPatch struct {
 }
 
 // removeTaintInBackground removes the taint from the node in a goroutine with retry logic
+// TODO: We could test this properly with synctest when we move to go 1.25
 func removeTaintInBackground(k8sClient kubernetes.Interface, nodeName, driverName string, backoff wait.Backoff, removalFunc func(kubernetes.Interface, string, string) error) {
 	klog.V(2).Infof("starting background node taint removal for node %s", nodeName)
 	go func() {

pkg/azurelustre/azurelustre_test.go

@@ -131,14 +131,54 @@ func (f *FakeDynamicProvisioner) GetSkuValuesForLocation(_ context.Context, loca
 }
 
 func TestNewDriver(t *testing.T) {
+	fakeConfigFile := "fake-cred-file.json"
+	fakeConfigContent := `{
+    "tenantId": "fake-tenant-id",
+    "subscriptionId": "fake-subscription-id",
+    "aadClientId": "fake-client-id",
+    "aadClientSecret": "fake-client-secret",
+    "resourceGroup": "fake-resource-group",
+    "location": "fake-location",
+}`
+
+	if err := os.WriteFile(fakeConfigFile, []byte(fakeConfigContent), 0o600); err != nil {
+		t.Error(err)
+	}
+
+	defer func() {
+		if err := os.Remove(fakeConfigFile); err != nil {
+			t.Error(err)
+		}
+	}()
+
+	t.Setenv(DefaultAzureConfigFileEnv, fakeConfigFile)
+
 	driverOptions := DriverOptions{
 		NodeID:                       fakeNodeID,
-		DriverName:                   DefaultDriverName,
+		DriverName:                   fakeDriverName,
 		EnableAzureLustreMockMount:   false,
 		EnableAzureLustreMockDynProv: true,
+		WorkingMountDir:              "/tmp",
+		RemoveNotReadyTaint:          true,
 	}
 	d := NewDriver(&driverOptions)
 	assert.NotNil(t, d)
+	assert.NotNil(t, d.cloud)
+	assert.NotNil(t, d.dynamicProvisioner)
+	assert.Equal(t, "fake-resource-group", d.resourceGroup)
+	assert.Equal(t, "fake-location", d.location)
+	assert.Equal(t, fakeNodeID, d.NodeID)
+	assert.Equal(t, fakeDriverName, d.Name)
+	assert.Equal(t, "fake-subscription-id", d.cloud.SubscriptionID)
+	assert.Equal(t, "fake-tenant-id", d.cloud.TenantID)
+	assert.Equal(t, "fake-client-id", d.cloud.AADClientID)
+	assert.Equal(t, "fake-client-secret", d.cloud.AADClientSecret)
+	assert.Equal(t, "fake-location", d.cloud.Location)
+	assert.Equal(t, "fake-resource-group", d.cloud.ResourceGroup)
+	assert.Equal(t, "/tmp", d.workingMountDir)
+	assert.True(t, d.enableAzureLustreMockDynProv, "enableAzureLustreMockDynProv should be true")
+	assert.False(t, d.enableAzureLustreMockMount, "enableAzureLustreMockMount should be false")
+	assert.True(t, d.removeNotReadyTaint, "removeNotReadyTaint should be true")
 }
 
 func TestIsCorruptedDir(t *testing.T) {