Make Hands-Off Zero-Touch Enrollment compatibile with tests

chrome/browser/chromeos/login/screens/update_screen.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/chromeos/login/screens/update_screen.h"
 
 #include <algorithm>
 
 #include "base/bind.h"
 #include "base/files/file_util.h"
@@ skipping 223 matching lines @@
   }
 
   switch (status.status) {
     case UpdateEngineClient::UPDATE_STATUS_CHECKING_FOR_UPDATE:
       // Do nothing in these cases, we don't want to notify the user of the
       // check unless there is an update.
       SetHostPairingControllerStatus(
           HostPairingController::UPDATE_STATUS_UPDATING);
       break;
     case UpdateEngineClient::UPDATE_STATUS_UPDATE_AVAILABLE:
+      RecordUpdateCheckResultingInUpdate();
       MakeSureScreenIsShown();
       GetContextEditor()
           .SetInteger(kContextKeyProgress, kBeforeDownloadProgress)
           .SetBoolean(kContextKeyShowEstimatedTimeLeft, false);
       if (!HasCriticalUpdate()) {
         VLOG(1) << "Noncritical update available: " << status.new_version;
         ExitUpdate(REASON_UPDATE_NON_CRITICAL);
       } else {
         VLOG(1) << "Critical update available: " << status.new_version;
         GetContextEditor()
@@ skipping 291 matching lines @@
 }
 
 void UpdateScreen::StartUpdateCheck() {
   error_message_timer_.Stop();
   GetErrorScreen()->HideCaptivePortal();
 
   network_portal_detector::GetInstance()->RemoveObserver(this);
   connect_request_subscription_.reset();
   if (state_ == State::STATE_ERROR)
     HideErrorMessage();
-  state_ = State::STATE_UPDATE;
-  DBusThreadManager::Get()->GetUpdateEngineClient()->AddObserver(this);
-  VLOG(1) << "Initiate update check";
-  DBusThreadManager::Get()->GetUpdateEngineClient()->RequestUpdateCheck(
-      base::Bind(StartUpdateCallback, this));
+
+  if (ShouldCheckForUpdate()) {
+    state_ = State::STATE_UPDATE;
+    DBusThreadManager::Get()->GetUpdateEngineClient()->AddObserver(this);
+    VLOG(1) << "Initiate update check";
+    RecordUpdateCheckWithNoUpdateYet();
+    DBusThreadManager::Get()->GetUpdateEngineClient()->RequestUpdateCheck(
+        base::Bind(StartUpdateCallback, this));
+  } else {
+    LOG(WARNING) << "Skipping update check since one was done recently "
+                    "which did not result in an update.";
+    CancelUpdate();
+  }
 }
 
 void UpdateScreen::ShowErrorMessage() {
   LOG(WARNING) << "UpdateScreen::ShowErrorMessage()";
 
   error_message_timer_.Stop();
 
   state_ = State::STATE_ERROR;
   connect_request_subscription_ =
       GetErrorScreen()->RegisterConnectRequestCallback(base::Bind(
@@ skipping 50 matching lines @@
       &UpdateScreen::ShowErrorMessage);
 }
 
 void UpdateScreen::OnConnectRequested() {
   if (state_ == State::STATE_ERROR) {
     LOG(WARNING) << "Hiding error message since AP was reselected";
     StartUpdateCheck();
   }
 }
 
+void UpdateScreen::RecordUpdateCheckWithNoUpdateYet() {
+  StartupUtils::SaveTimeOfLastUpdateCheckWithoutUpdate(base::Time::Now());
+}
+
+void UpdateScreen::RecordUpdateCheckResultingInUpdate() {

[xiyuan, 2017/05/15 17:24:22]

This name is confusing. How about call it ClearUpdateCheckNoUpdateTime() ? And
expose an explicit clear mthod from StartupUtils instead of writing a 0.

[kumarniranjan, 2017/05/15 22:08:21]

Done.

+  StartupUtils::SaveTimeOfLastUpdateCheckWithoutUpdate(base::Time::UnixEpoch());
+}
+
+bool UpdateScreen::ShouldCheckForUpdate() {
+  // Always run update check for non hands-off enrollment.
+  if (!WizardController::UsingHandsOffEnrollment())
+    return true;
+
+  // If we check for an update and there is no need to perform an update,
+  // this is the time in hours we should wait before checking again.
+  const base::TimeDelta kUpdateCheckRecencyThreshold =
+      base::TimeDelta::FromHours(1);
+
+  base::Time now = base::Time::Now();
+  base::Time last = StartupUtils::GetTimeOfLastUpdateCheckWithoutUpdate();
+
+  // Return false if enough time has not passed since the last update check.
+  // Otherwise, return true.
+  if (now > last) {
+    return (now - last) > kUpdateCheckRecencyThreshold;
+  } else {

[xiyuan, 2017/05/15 17:24:22]

nit: get rid of "else"

[kumarniranjan, 2017/05/15 22:08:21]

Done.

+    return true;
+  }
+}
+
 }  // namespace chromeos