Apply default wallpaper from customization manifest.

chrome/browser/chromeos/customization_wallpaper_downloader.cc

+// Copyright 2014 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/customization_wallpaper_downloader.h"
+
+#include "base/file_util.h"
+#include "content/public/browser/browser_thread.h"
+#include "net/base/load_flags.h"
+#include "net/http/http_status_code.h"
+#include "net/url_request/url_request_context_getter.h"
+#include "url/gurl.h"
+
+namespace chromeos {
+namespace {
+// This is temporary file suffix (for downloading or resizing).
+const char kTemporarySuffix[] = ".tmp";
+
+// Sleep between wallpaper retries (used multiplied by squared retry number).
+const unsigned kRetrySleepSeconds = 10;
+
+// Retry is infinite with increasing intervals. When calculated delay becomes
+// longer than maximum (kMaxRetryDelaySeconds) it is set to the maximim.

[Daniel Erat, 2014/04/16 15:35:41]

nit: s/maximim/maximum/

[Alexander Alekseev, 2014/04/16 23:19:59]

Done.

+const int kMaxRetryDelaySeconds = 6 * 3600;  // 6 hours

[Daniel Erat, 2014/04/16 15:35:41]

nit: be consistent wrt "Sleep" and "Delay" between this constant and the above
one

[Alexander Alekseev, 2014/04/16 23:19:59]

Done.

+
+void CreateWallpaperDirectory(const base::FilePath& wallpaper_dir,
+                              bool* success) {
+  DCHECK(content::BrowserThread::GetBlockingPool()->RunsTasksOnCurrentThread());
+  DCHECK(success);
+
+  *success = CreateDirectoryAndGetError(wallpaper_dir, NULL);
+  if (!*success) {
+    NOTREACHED() << "Failed to creare directory '" << wallpaper_dir.value()

[Daniel Erat, 2014/04/16 15:35:41]

nit: s/creare/create/

[Alexander Alekseev, 2014/04/16 23:19:59]

Done.

+                 << "'";
+  }
+}
+
+void RenameTemporaryFile(const base::FilePath& from,
+                         const base::FilePath& to,
+                         bool* success) {
+  DCHECK(content::BrowserThread::GetBlockingPool()->RunsTasksOnCurrentThread());
+  DCHECK(success);
+
+  base::File::Error error;
+  if (base::ReplaceFile(from, to, &error)) {
+    *success = true;
+  } else {
+    LOG(WARNING)
+        << "Failed to rename temporary file of Customized Wallpaper. error="
+        << error;
+    *success = false;
+  }
+}
+
+}  // namespace
+
+CustomizationWallpaperDownloader::CustomizationWallpaperDownloader(
+    net::URLRequestContextGetter* url_context_getter,
+    const GURL& wallpaper_url,
+    const base::FilePath& wallpaper_dir,
+    const base::FilePath& wallpaper_downloaded_file,
+    base::Callback<void(bool success, const GURL&)>
+        on_wallpaper_fetch_completed)
+    : url_context_getter_(url_context_getter),
+      wallpaper_url_(wallpaper_url),
+      wallpaper_dir_(wallpaper_dir),
+      wallpaper_downloaded_file_(wallpaper_downloaded_file),
+      wallpaper_temporary_file_(wallpaper_downloaded_file.value() +
+                                kTemporarySuffix),
+      retries_(0),
+      on_wallpaper_fetch_completed_(on_wallpaper_fetch_completed),
+      weak_factory_(this) {
+  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
+}
+
+CustomizationWallpaperDownloader::~CustomizationWallpaperDownloader() {
+  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
+}
+
+void CustomizationWallpaperDownloader::StartRequest() {
+  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
+  DCHECK(wallpaper_url_.is_valid());
+
+  url_fetcher_.reset(
+      net::URLFetcher::Create(wallpaper_url_, net::URLFetcher::GET, this));
+  url_fetcher_->SetRequestContext(url_context_getter_);
+  url_fetcher_->SetLoadFlags(net::LOAD_BYPASS_CACHE |
+                             net::LOAD_DISABLE_CACHE |
+                             net::LOAD_DO_NOT_SAVE_COOKIES |
+                             net::LOAD_DO_NOT_SEND_COOKIES |
+                             net::LOAD_DO_NOT_SEND_AUTH_DATA);
+  base::SequencedWorkerPool* blocking_pool =
+      content::BrowserThread::GetBlockingPool();
+  url_fetcher_->SaveResponseToFileAtPath(
+      wallpaper_temporary_file_,
+      blocking_pool->GetSequencedTaskRunner(blocking_pool->GetSequenceToken()));
+  url_fetcher_->Start();
+}
+
+void CustomizationWallpaperDownloader::Retry() {
+  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
+  ++retries_;
+
+  const bool ignore_retries =
+      retries_ * double(retries_) * kRetrySleepSeconds >= kMaxRetryDelaySeconds;

[Daniel Erat, 2014/04/16 15:35:41]

few things:
- use static_cast instead
- i think i've convinced myself that this is safe (i.e. it'll become infinity
instead of overflowing), but please add a comment explaining this
- something like this is simpler and equivalent, i think (you'll need to change
the constant to a double):

  const double delay_seconds = std::min(kMaxRetryDelaySeconds,
      static_cast<double>(retries_) * retries_ * kRetrySleepSeconds);
  const base::TimeDelta delay = base::TimeDelta::FromSeconds(
      lround(delay_seconds));

[Alexander Alekseev, 2014/04/16 23:19:59]

Done.

+
+  base::TimeDelta delay =
+      ignore_retries ? base::TimeDelta::FromSeconds(kRetrySleepSeconds)

[Daniel Erat, 2014/04/16 15:35:41]

you'd need kMaxRetryDelaySeconds here, but see above

[Alexander Alekseev, 2014/04/16 23:19:59]

Done.

+                     : base::TimeDelta::FromSeconds(kRetrySleepSeconds) *
+                           retries_ * retries_;
+  VLOG(1) << "Schedule Customized Wallpaper download in " << delay.InSecondsF()
+          << " seconds (retry = " << retries_ << ").";
+  request_scheduled_.Start(
+      FROM_HERE, delay, this, &CustomizationWallpaperDownloader::StartRequest);
+}
+
+void CustomizationWallpaperDownloader::Start() {
+  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
+  scoped_ptr<bool> success(new bool(false));
+
+  base::Closure mkdir_closure = base::Bind(&CreateWallpaperDirectory,
+                                           wallpaper_dir_,
+                                           base::Unretained(success.get()));
+  base::Closure on_created_closure =
+      base::Bind(&CustomizationWallpaperDownloader::OnWallpaperDirectoryCreated,
+                 weak_factory_.GetWeakPtr(),
+                 base::Passed(success.Pass()));
+  if (!content::BrowserThread::PostBlockingPoolTaskAndReply(
+          FROM_HERE, mkdir_closure, on_created_closure)) {
+    LOG(WARNING) << "Failed to start Customized Wallpaper download.";
+  }
+}
+
+void CustomizationWallpaperDownloader::OnWallpaperDirectoryCreated(
+    scoped_ptr<bool> success) {
+  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
+  if (*success)
+    StartRequest();
+}
+
+void CustomizationWallpaperDownloader::OnURLFetchComplete(
+    const net::URLFetcher* source) {
+  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
+  DCHECK_EQ(url_fetcher_.get(), source);
+
+  const net::URLRequestStatus status = source->GetStatus();
+  const int response_code = source->GetResponseCode();
+
+  const bool server_error =
+      !status.is_success() ||
+      (response_code >= net::HTTP_INTERNAL_SERVER_ERROR &&
+       response_code < (net::HTTP_INTERNAL_SERVER_ERROR + 100));
+
+  VLOG(1) << "CustomizationWallpaperDownloader::OnURLFetchComplete(): status="
+          << status.status();
+
+  if (server_error) {
+    url_fetcher_.reset();
+    Retry();
+    return;
+  }
+
+  base::FilePath response_path;
+  url_fetcher_->GetResponseAsFilePath(true, &response_path);
+  url_fetcher_.reset();
+
+  scoped_ptr<bool> success(new bool(false));
+
+  base::Closure rename_closure = base::Bind(&RenameTemporaryFile,
+                                            response_path,
+                                            wallpaper_downloaded_file_,
+                                            base::Unretained(success.get()));
+  base::Closure on_rename_closure =
+      base::Bind(&CustomizationWallpaperDownloader::OnTemporaryFileRenamed,
+                 weak_factory_.GetWeakPtr(),
+                 base::Passed(success.Pass()));
+  if (!content::BrowserThread::PostBlockingPoolTaskAndReply(
+          FROM_HERE, rename_closure, on_rename_closure)) {
+    LOG(WARNING)
+        << "Failed to start Customized Wallpaper Rename DownloadedFile.";
+    on_wallpaper_fetch_completed_.Run(false, wallpaper_url_);
+  }
+}
+
+void CustomizationWallpaperDownloader::OnTemporaryFileRenamed(
+    scoped_ptr<bool> success) {
+  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
+  on_wallpaper_fetch_completed_.Run(*success, wallpaper_url_);
+}
+
+}  //   namespace chromeos