Add restart route for atomicity

src/apps.js

@@ -43,6 +43,7 @@ exports = module.exports = {
 
     start: start,
     stop: stop,
+    restart: restart,
 
     exec: exec,
 
@@ -79,6 +80,7 @@ exports = module.exports = {
     ISTATE_PENDING_BACKUP: 'pending_backup', // backup the app. this is state because it blocks other operations
     ISTATE_PENDING_START: 'pending_start',
     ISTATE_PENDING_STOP: 'pending_stop',
+    ISTATE_PENDING_RESTART: 'pending_restart',
     ISTATE_ERROR: 'error', // error executing last pending_* command
     ISTATE_INSTALLED: 'installed', // app is installed
 
@@ -1678,6 +1680,30 @@ function stop(appId, callback) {
     });
 }
 
+function restart(appId, callback) {
+    assert.strictEqual(typeof appId, 'string');
+    assert.strictEqual(typeof callback, 'function');
+
+    debug('Will restart app with id:%s', appId);
+
+    get(appId, function (error, app) {
+        if (error) return callback(error);
+
+        error = checkAppState(app, exports.ISTATE_PENDING_RESTART);
+        if (error) return callback(error);
+
+        const task = {
+            args: {},
+            values: { runState: exports.RSTATE_RUNNING }
+        };
+        addTask(appId, exports.ISTATE_PENDING_RESTART, task, function (error, result) {
+            if (error) return callback(error);
+
+            callback(null, { taskId: result.taskId });
+        });
+    });
+}
+
 function checkManifestConstraints(manifest) {
     assert(manifest && typeof manifest === 'object');