Create AccountServiceFlagFetcher which downloads an account's Gaia service flags.

chrome/browser/signin/account_service_flag_fetcher.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/signin/account_service_flag_fetcher.h"
+
+#include "base/strings/string_split.h"
+#include "chrome/browser/profiles/profile.h"
+#include "chrome/browser/signin/profile_oauth2_token_service_factory.h"
+#include "chrome/browser/signin/signin_manager_factory.h"
+#include "components/signin/core/browser/profile_oauth2_token_service.h"
+#include "components/signin/core/browser/signin_manager.h"
+#include "google_apis/gaia/gaia_constants.h"
+
+AccountServiceFlagFetcher::AccountServiceFlagFetcher(Profile* profile)
+  : OAuth2TokenService::Consumer("account_service_flag_fetcher"),
+    profile_(profile),
+    gaia_auth_fetcher_(this, GaiaConstants::kChromeSource,
+                       profile->GetRequestContext()) {}
+
+AccountServiceFlagFetcher::~AccountServiceFlagFetcher() {
+  // Ensures PO2TS observation is cleared when AccountServiceFlagFetcher is
+  // destructed before refresh token is available.
+  ProfileOAuth2TokenService* service =
+      ProfileOAuth2TokenServiceFactory::GetForProfile(profile_);
+  service->RemoveObserver(this);
+}
+
+void AccountServiceFlagFetcher::Start(const Callback& callback) {
+  DCHECK(!IsPending());
+
+  callback_ = callback;
+
+  ProfileOAuth2TokenService* token_service =
+      ProfileOAuth2TokenServiceFactory::GetForProfile(profile_);
+  SigninManagerBase* signin_manager =
+      SigninManagerFactory::GetForProfile(profile_);
+  std::string account_id = signin_manager->GetAuthenticatedAccountId();
+  if (token_service->RefreshTokenIsAvailable(account_id)) {
+    StartFetchingOAuth2AccessToken(account_id);
+  } else {
+    // Wait until we get a refresh token.
+    token_service->AddObserver(this);
+  }
+}
+
+void AccountServiceFlagFetcher::Cancel() {
+  oauth2_access_token_request_.reset();
+  ProfileOAuth2TokenService* service =
+      ProfileOAuth2TokenServiceFactory::GetForProfile(profile_);
+  service->RemoveObserver(this);

[Andrew T Wilson (Slow), 2014/05/16 08:44:44]

Is it OK to call RemoveObserver() if you've never called AddObserver()?

[Marc Treib, 2014/05/20 10:46:40]

Yes.

+
+  gaia_auth_fetcher_.CancelRequest();
+
+  callback_.Reset();
+}
+
+bool AccountServiceFlagFetcher::IsPending() const {
+  return !callback_.is_null();
+}
+
+void AccountServiceFlagFetcher::OnRefreshTokenAvailable(
+    const std::string& account_id) {
+  // Wait until we get a refresh token for the primary (authenticated) account.
+  SigninManagerBase* signin_manager =
+      SigninManagerFactory::GetForProfile(profile_);
+  if (account_id != signin_manager->GetAuthenticatedAccountId())

[Andrew T Wilson (Slow), 2014/05/16 08:44:44]

Is it possible that you'll never get a token loaded for the authenticated
account? Should you listen for OnRefreshTokensLoaded() to catch this case?

[Marc Treib, 2014/05/20 10:46:40]

I suppose that can happen - so you're saying I should report an error when I get
OnRefreshTokensLoaded before OnRefreshTokenAvailable?
But couldn't it also happen that I still get a refresh token after
OnRefreshTokensLoaded, e.g. when UpdateCredentials is called directly?

[Andrew T Wilson (Slow), 2014/05/23 14:51:59]

Technically, yes.
That only happens if the user does a re-auth, which could happen hours or days
later. I think you want your callback invoked with an error much earlier than
that, rather than have it hang around, pending, for days waiting for the user to
notice an auth error and re-sign-in.

[Marc Treib, 2014/05/26 12:31:40]

Done.
However, if we call this after the tokens have been loaded with an account ID
for which we don't have a token, it will still hang around indefinitely. I don't
see a way to reliably detect this case. Maybe it's enough to document the
behavior in this case?

+    return;
+
+  ProfileOAuth2TokenService* token_service =
+      ProfileOAuth2TokenServiceFactory::GetForProfile(profile_);
+  token_service->RemoveObserver(this);
+
+  StartFetchingOAuth2AccessToken(account_id);
+}
+
+void AccountServiceFlagFetcher::StartFetchingOAuth2AccessToken(
+    const std::string& account_id) {
+  OAuth2TokenService::ScopeSet scopes;
+  scopes.insert(GaiaConstants::kOAuth1LoginScope);
+  ProfileOAuth2TokenService* token_service =
+      ProfileOAuth2TokenServiceFactory::GetForProfile(profile_);
+  oauth2_access_token_request_ = token_service->StartRequest(
+      account_id, scopes, this);
+}
+
+void AccountServiceFlagFetcher::OnGetTokenSuccess(
+    const OAuth2TokenService::Request* request,
+    const std::string& access_token,
+    const base::Time& expiration_time) {
+  DCHECK_EQ(oauth2_access_token_request_.get(), request);
+  oauth2_access_token_request_.reset();
+  ProfileOAuth2TokenService* service =
+      ProfileOAuth2TokenServiceFactory::GetForProfile(profile_);
+  service->RemoveObserver(this);
+
+  gaia_auth_fetcher_.StartOAuthLogin(access_token, GaiaConstants::kGaiaService);
+}
+
+void AccountServiceFlagFetcher::OnGetTokenFailure(
+    const OAuth2TokenService::Request* request,
+    const GoogleServiceAuthError& error) {
+  DCHECK_EQ(oauth2_access_token_request_.get(), request);
+  oauth2_access_token_request_.reset();
+  ProfileOAuth2TokenService* service =
+      ProfileOAuth2TokenServiceFactory::GetForProfile(profile_);
+  service->RemoveObserver(this);
+
+  DLOG(WARNING) << "AccountServiceFlagFetcher::OnGetTokenFailure: "
+                << error.ToString();
+  callback_.Reset();

[Andrew T Wilson (Slow), 2014/05/16 08:44:44]

Hmmm. So, the paradigm is that you call Start(), and if your request fails you
basically are never notified? That seems like a hard API to use - how can you
tell if your request failed, or if it's just taking a really long time? Consider
reporting errors somehow.

[Marc Treib, 2014/05/20 10:46:40]

I have added a status code to the callback to report errors.
Previously, you would have had to explicitly call IsPending to check if your
request was still there.

+}
+
+void AccountServiceFlagFetcher::OnClientLoginSuccess(
+    const ClientLoginResult& result) {
+  gaia_auth_fetcher_.StartGetUserInfo(result.lsid);
+}
+
+void AccountServiceFlagFetcher::OnClientLoginFailure(
+    const GoogleServiceAuthError& error) {
+  DLOG(WARNING) << "AccountServiceFlagFetcher::OnClientLoginFailure: "
+                << error.ToString();
+  callback_.Reset();
+}
+
+void AccountServiceFlagFetcher::OnGetUserInfoSuccess(const UserInfoMap& data) {
+  std::vector<std::string> services;
+  UserInfoMap::const_iterator services_iter = data.find("allServices");
+  if (services_iter != data.end()) {
+    base::SplitString(services_iter->second, ',', &services);
+  } else {
+    DLOG(WARNING) << "AccountServiceFlagFetcher::OnGetUserInfoSuccess: "
+                  << "GetUserInfo response didn't include allServices field.";
+  }
+  callback_.Run(services);
+  callback_.Reset();
+}
+
+void AccountServiceFlagFetcher::OnGetUserInfoFailure(
+    const GoogleServiceAuthError& error) {
+  DLOG(WARNING) << "AccountServiceFlagFetcher::OnGetUserInfoFailure: "
+                << error.ToString();
+  callback_.Reset();
+}