[GCM] Handling connection events in GCMAccountTracker

chrome/browser/services/gcm/gcm_account_tracker.h

 // 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.
 
 #ifndef CHROME_BROWSER_SERVICES_GCM_GCM_ACCOUNT_TRACKER_H_
 #define CHROME_BROWSER_SERVICES_GCM_GCM_ACCOUNT_TRACKER_H_
 
 #include <map>
 #include <string>
 
 #include "base/memory/scoped_vector.h"
 #include "components/gcm_driver/gcm_client.h"
+#include "components/gcm_driver/gcm_connection_observer.h"
 #include "google_apis/gaia/account_tracker.h"
 #include "google_apis/gaia/oauth2_token_service.h"
 
 namespace gcm {
 
+class GCMDriver;
+
 // Class for reporting back which accounts are signed into. It is only meant to
 // be used when the user is signed into sync.
 class GCMAccountTracker : public gaia::AccountTracker::Observer,
-                          public OAuth2TokenService::Consumer {
+                          public OAuth2TokenService::Consumer,
+                          public GCMConnectionObserver {
  public:
   // State of the account.
   // Allowed transitions:
   // TOKEN_NEEDED - account info was created.
   // TOKEN_NEEDED -> GETTING_TOKEN - access token was requested.
   // GETTING_TOKEN -> TOKEN_NEEDED - access token fetching failed.
   // GETTING_TOKEN -> TOKEN_PRESENT - access token fetching succeeded.
   // GETTING_TOKEN -> ACCOUNT_REMOVED - account was removed.
   // TOKEN_NEEDED -> ACCOUNT_REMOVED - account was removed.
   // TOKEN_PRESENT -> ACCOUNT_REMOVED - account was removed.
   enum AccountState {
     TOKEN_NEEDED,     // Needs a token (AccountInfo was recently created or
                       // token request failed).
     GETTING_TOKEN,    // There is a pending token request.
     TOKEN_PRESENT,    // We have a token for the account.
     ACCOUNT_REMOVED,  // Account was removed, and we didn't report it yet.
   };
 
   // Stores necessary account information and state of token fetching.
   struct AccountInfo {
     AccountInfo(const std::string& email, AccountState state);
     ~AccountInfo();
 
     // Email address of the tracked account.
     std::string email;
     // OAuth2 access token, when |state| is TOKEN_PRESENT.
     std::string access_token;
+    // Expiration time of the access tokens.
+    base::Time expiration_time;
     // Status of the token fetching.
     AccountState state;
   };
 
-  // Callback for the GetAccountsForCheckin call. |account_tokens|: list of
-  // email addresses, account ids and OAuth2 access tokens.
-  typedef base::Callback<void(const std::vector<GCMClient::AccountTokenInfo>&
-                                  account_tokens)> UpdateAccountsCallback;
-
   // Creates an instance of GCMAccountTracker. |account_tracker| is used to
-  // deliver information about the account, while |callback| will be called
-  // once all of the accounts have been fetched a necessary OAuth2 token, as
-  // many times as the list of accounts is stable, meaning that all accounts
-  // are known and there is no related activity in progress for them, like
-  // fetching OAuth2 tokens.
+  // deliver information about the accounts present in the browser context to
+  // |driver|.
   GCMAccountTracker(scoped_ptr<gaia::AccountTracker> account_tracker,
-                    const UpdateAccountsCallback& callback);
+                    GCMDriver* driver);
   virtual ~GCMAccountTracker();
 
   // Shuts down the tracker ensuring a proper clean up. After Shutdown() is
   // called Start() and Stop() should no longer be used. Must be called before
   // destruction.
   void Shutdown();
 
   // Starts tracking accounts.
   void Start();
-  // Stops tracking accounts. Cancels all of the pending token requests.
-  void Stop();
+
+  // Gets the number of pending token requests. Only used for testing.
+  size_t get_pending_token_request_count() const {
+    return pending_token_requests_.size();
+  }
 
  private:
   // Maps account keys to account states. Keyed by account_ids as used by
   // OAuth2TokenService.
   typedef std::map<std::string, AccountInfo> AccountInfos;
 
   // AccountTracker::Observer overrides.
   virtual void OnAccountAdded(const gaia::AccountIds& ids) OVERRIDE;
   virtual void OnAccountRemoved(const gaia::AccountIds& ids) OVERRIDE;
   virtual void OnAccountSignInChanged(const gaia::AccountIds& ids,
                                       bool is_signed_in) OVERRIDE;
 
   // OAuth2TokenService::Consumer overrides.
   virtual void OnGetTokenSuccess(const OAuth2TokenService::Request* request,
                                  const std::string& access_token,
                                  const base::Time& expiration_time) OVERRIDE;
   virtual void OnGetTokenFailure(const OAuth2TokenService::Request* request,
                                  const GoogleServiceAuthError& error) OVERRIDE;
 
+  // GCMConnectionObserver overrides.
+  virtual void OnConnected(const net::IPEndPoint& ip_endpoint) OVERRIDE;
+  virtual void OnDisconnected() OVERRIDE;
+
   // Report the list of accounts with OAuth2 tokens back using the |callback_|
   // function. If there are token requests in progress, do nothing.
   void CompleteCollectingTokens();
+  // Verify that all of the tokens are ready to be passed down to the GCM
+  // Driver, e.g. none of them has expired or is missing. Returns true if not
+  // all tokens are valid and a fetching yet more tokens is required.
+  bool SanitizeTokens();
   // Deletes a token request. Should be called from OnGetTokenSuccess(..) or
   // OnGetTokenFailure(..).
   void DeleteTokenRequest(const OAuth2TokenService::Request* request);
   // Checks on all known accounts, and calls GetToken(..) for those with
   // |state == TOKEN_NEEDED|.
   void GetAllNeededTokens();
   // Starts fetching the OAuth2 token for the GCM group scope.
   void GetToken(AccountInfos::iterator& account_iter);
 
   // Handling of actual sign in and sign out for accounts.
   void OnAccountSignedIn(const gaia::AccountIds& ids);
   void OnAccountSignedOut(const gaia::AccountIds& ids);
 
   OAuth2TokenService* GetTokenService();
 
   // Account tracker.
   scoped_ptr<gaia::AccountTracker> account_tracker_;
 
-  // Callback to be called after all of the account and OAuth2 tokens are
-  // collected.
-  UpdateAccountsCallback callback_;
+  // GCM Driver. Not owned.
+  GCMDriver* driver_;
 
   // State of the account.
   AccountInfos account_infos_;
 
   // Indicates whether shutdown has been called.
   bool shutdown_called_;
 
   ScopedVector<OAuth2TokenService::Request> pending_token_requests_;
 
   DISALLOW_COPY_AND_ASSIGN(GCMAccountTracker);
 };
 
 }  // namespace gcm
 
 #endif  // CHROME_BROWSER_SERVICES_GCM_GCM_ACCOUNT_TRACKER_H_