If customization includes default wallpaper, download and apply it.

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/url_request/url_request_context_getter.h"
+#include "url/gurl.h"
+
+namespace {
+// This is temporary file suffix (for downloading or resizing).
+const char kTemporarySuffix[] = ".temp";
+
+// Sleep between wallpaper retries (used multiplied by retry number).
+const unsigned kRetrySleepSeconds = 10;
+
+// Do not increase retry sleep beyond this number of attempts.
+const unsigned kRetriesInfinite = 30;
+}
+
+namespace chromeos {
+
+CustomizationWallpaperDownloader::CustomizationWallpaperDownloader(
+    net::URLRequestContextGetter* url_context_getter,
+    const GURL& wallpaper_url,
+    const base::FilePath& wallpaper_dir,
+    const base::FilePath& wallpaper_downloaded_file)
+    : 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),
+      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());
+  ++retries_;
+
+  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));
+  const unsigned delay_multiplier =
+      (retries_ > kRetriesInfinite ? kRetriesInfinite : retries_);
+  const base::TimeDelta delay =
+      base::TimeDelta::FromSeconds(kRetrySleepSeconds) * delay_multiplier;
+  VLOG(1) << "Schedule Customized Wallpaper download in " << delay.InSecondsF()
+          << " seconds.";
+  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(&CustomizationWallpaperDownloader::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.";
+  }
+}
+
+// static
+void CustomizationWallpaperDownloader::CreateWallpaperDirectory(
+    const base::FilePath& wallpaper_dir,
+    bool* success) {
+  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::FILE));
+  DCHECK(success);
+
+  base::File::Error error;
+  if (CreateDirectoryAndGetError(wallpaper_dir, &error)) {
+    *success = true;
+  } else {
+    *success = false;
+  }
+}
+
+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 >= 500 && response_code < 600);
+
+  VLOG(1) << "CustomizationWallpaperDownloader::OnURLFetchComplete(): status="
+          << status.status();
+
+  if (server_error) {
+    url_fetcher_.reset();
+    Retry();

[Mattias Nissler (ping if slow), 2014/03/24 20:38:54]

So this keeps retrying forever. Is that intentional? I guess you should give up
at some point.

[Alexander Alekseev, 2014/03/25 14:38:29]

Why? May be we should increase retry sleep...

+    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(&CustomizationWallpaperDownloader::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.";
+    // Destroy self.
+    ServicesCustomizationDocument::DestroyWallpaperDownloader();
+  }
+}
+
+void CustomizationWallpaperDownloader::OnTemporaryFileRenamed(
+    scoped_ptr<bool> success) {
+  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
+  if (!success) {
+    // Destroy self.
+    ServicesCustomizationDocument::DestroyWallpaperDownloader();
+    return;
+  }
+  ServicesCustomizationDocument::SetDefaultWallpaperPath(wallpaper_url_);

[Mattias Nissler (ping if slow), 2014/03/24 20:38:54]

The use of static functions for reporting success and self-destruction seems
like a hack to me. The standard solution to this problem is to have the owning
class pass a callback to the ctor that gets invoked with success or error status
and then the caller can destroy the downloader object.

[Alexander Alekseev, 2014/03/25 14:38:29]

I've recently received comment (in another CL) that self-destroying callbacks
are confusing (even with comment), and had to change it to direct calls to
"owner->DestroySelf()" ;-)

So I'd leave this decision to dpolukhin.

+}
+
+// static
+void CustomizationWallpaperDownloader::RenameTemporaryFile(
+    const base::FilePath& from,
+    const base::FilePath& to,
+    bool* success) {
+  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::FILE));
+  DCHECK(success);
+
+  base::File::Error error;
+  if (ReplaceFile(from, to, &error)) {
+    *success = true;
+  } else {
+    LOG(WARNING)
+        << "Failed to rename temporary file of Customized Wallpaper. error="
+        << error;
+    *success = false;
+  }
+}
+
+}  //   namespace chromeos