Fix pre-shared key not persistent (#1011)

* update pre-shared key if new key is not empty

* add unit test for empty pre-shared key

client/internal/config.go

@@ -215,10 +215,12 @@ func update(input ConfigInput) (*Config, error) {
 	}
 
 	if input.PreSharedKey != nil && config.PreSharedKey != *input.PreSharedKey {
-		log.Infof("new pre-shared key provided, updated to %s (old value %s)",
+		if *input.PreSharedKey != "" {
-			*input.PreSharedKey, config.PreSharedKey)
+			log.Infof("new pre-shared key provides, updated to %s (old value %s)",
-		config.PreSharedKey = *input.PreSharedKey
+				*input.PreSharedKey, config.PreSharedKey)
-		refresh = true
+			config.PreSharedKey = *input.PreSharedKey
+			refresh = true
+		}
 	}
 
 	if config.SSHKey == "" {

client/internal/config_test.go

@@ -63,7 +63,22 @@ func TestGetConfig(t *testing.T) {
 	assert.Equal(t, config.ManagementURL.String(), managementURL)
 	assert.Equal(t, config.PreSharedKey, preSharedKey)
 
-	// case 4: existing config, but new managementURL has been provided -> update config
+	// case 4: new empty pre-shared key config -> fetch it
+	newPreSharedKey := ""
+	config, err = UpdateOrCreateConfig(ConfigInput{
+		ManagementURL: managementURL,
+		AdminURL:      adminURL,
+		ConfigPath:    path,
+		PreSharedKey:  &newPreSharedKey,
+	})
+	if err != nil {
+		return
+	}
+
+	assert.Equal(t, config.ManagementURL.String(), managementURL)
+	assert.Equal(t, config.PreSharedKey, preSharedKey)
+
+	// case 5: existing config, but new managementURL has been provided -> update config
 	newManagementURL := "https://test.newManagement.url:33071"
 	config, err = UpdateOrCreateConfig(ConfigInput{
 		ManagementURL: newManagementURL,