GUACAMOLE-1904: Disable ManagedArgument instead of deleting when updated, to avoid fields disappearing upon modification.

guacamole/src/main/frontend/src/app/client/types/ManagedArgument.js

@@ -58,6 +58,16 @@ angular.module('client').factory('ManagedArgument', ['$q', function defineManage
          */
         this.stream = template.stream;
 
+        /**
+         * True if this argument has been modified in the webapp, but yet to
+         * be confirmed by guacd, or false in any other case. A pending
+         * argument cannot be modified again, and must be recreated before
+         * editing is enabled again.
+         *
+         * @type {boolean}
+         */
+        this.pending = false;
+
     };
 
     /**
@@ -110,9 +120,9 @@ angular.module('client').factory('ManagedArgument', ['$q', function defineManage
      * Sets the given editable argument (connection parameter) to the given
      * value, updating the behavior of the associated connection in real-time.
      * If successful, the ManagedArgument provided cannot be used for future
-     * calls to setValue() and must be replaced with a new instance. This
-     * function only has an effect if the new parameter value is different from
-     * the current value.
+     * calls to setValue() and will be read-only until replaced with a new
+     * instance. This function only has an effect if the new parameter value
+     * is different from the current value.
      *
      * @param {ManagedArgument} managedArgument
      *     The ManagedArgument instance associated with the connection
@@ -120,31 +130,22 @@ angular.module('client').factory('ManagedArgument', ['$q', function defineManage
      *
      * @param {String} value
      *     The new value to assign to the connection parameter.
-     *
-     * @returns {Boolean}
-     *     true if the connection parameter was sent and the provided
-     *     ManagedArgument instance may no longer be used for future setValue()
-     *     calls, false if the connection parameter was NOT sent as it has not
-     *     changed.
      */
     ManagedArgument.setValue = function setValue(managedArgument, value) {
 
-        // Stream new value only if value has changed
-        if (value !== managedArgument.value) {
+        // Stream new value only if value has changed and a change is not
+        // already pending
+        if (!managedArgument.pending && value !== managedArgument.value) {
 
             var writer = new Guacamole.StringWriter(managedArgument.stream);
             writer.sendText(value);
             writer.sendEnd();
 
             // ManagedArgument instance is no longer usable
-            return true;
+            managedArgument.pending = true;
 
         }
 
-        // No parameter value change was attempted and the ManagedArgument
-        // instance may be reused
-        return false;
-
     };
 
     return ManagedArgument;

guacamole/src/main/frontend/src/app/client/types/ManagedClient.js

@@ -836,8 +836,7 @@ angular.module('client').factory('ManagedClient', ['$rootScope', '$injector',
      */
     ManagedClient.setArgument = function setArgument(managedClient, name, value) {
         var managedArgument = managedClient.arguments[name];
-        if (managedArgument && ManagedArgument.setValue(managedArgument, value))
-            delete managedClient.arguments[name];
+        managedArgument && ManagedArgument.setValue(managedArgument, value);
     };
 
     /**

guacamole/src/main/frontend/src/app/form/directives/form.js

@@ -17,6 +17,7 @@
  * under the License.
  */
 
+/* global _ */
 
 /**
  * A directive that allows editing of a collection of fields.
@@ -84,6 +85,11 @@ angular.module('form').directive('guacForm', [function form() {
             /**
              * The client associated with this form, if any.
              *
+             * NOTE: If the provided client has any managed arguments in the
+             * pending state, any fields with the same name rendered by this
+             * form will be disabled. The fields will be re-enabled when guacd
+             * sends an updated argument with a the same name.
+             *
              * @type ManagedClient
              */
             client: '='
@@ -247,6 +253,28 @@ angular.module('form').directive('guacForm', [function form() {
 
             };
 
+
+            /**
+             * Returns whether the given field should be disabled (read-only)
+             * when presented to the current user.
+             *
+             * @param {Field} field
+             *     The field to check.
+             *
+             * @returns {Boolean}
+             *     true if the given field should be disabled, false otherwise.
+             */
+            $scope.isDisabled = function isDisabled(field) {
+
+                /*
+                 * The field is disabled if either the form as a whole is disabled,
+                 * or if a client is provided to the directive, and the field is
+                 * marked as pending.
+                 */
+                return $scope.disabled ||
+                        _.get($scope.client, ['arguments', field.name, 'pending']);
+            };
+
             /**
              * Returns whether at least one of the given fields should be
              * displayed to the current user.

guacamole/src/main/frontend/src/app/form/templates/form.html

@@ -10,7 +10,7 @@
         <div class="fields">
             <guac-form-field ng-repeat="field in form.fields" namespace="namespace"
                              ng-if="isVisible(field)"
-                             data-disabled="disabled"
+                             data-disabled="isDisabled(field)"
                              focused="isFocused(field)"
                              field="field"
                              client="client"