Build a new TokenCacheService so I can stop using TokenService for something it wasn't designed for.

chrome/browser/extensions/api/token_cache/token_cache.h

+// Copyright (c) 2013 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.
+
+// This class caches tokens for the current user.  It will clear tokens out
+// when the user logs out or after the specified timeout interval, or when
+// the instance of chrome shuts down.
+
+#ifndef CHROME_BROWSER_EXTENSIONS_API_TOKEN_CACHE_TOKEN_CACHE_H_
+#define CHROME_BROWSER_EXTENSIONS_API_TOKEN_CACHE_TOKEN_CACHE_H_
+
+#include <string>
+#include <vector>
+
+#include "base/basictypes.h"
+#include "base/compiler_specific.h"
+#include "base/time.h"
+#include "chrome/browser/profiles/profile_keyed_service.h"
+#include "content/public/browser/notification_observer.h"
+#include "content/public/browser/notification_registrar.h"
+#include "content/public/browser/notification_service.h"

[dcheng, 2013/03/04 22:40:59]

I think this include isn't needed.

[Pete Williamson, 2013/03/05 19:42:25]

Nope, we need it for content::Source<Profile>

+
+class Profile;
+
+struct TokenCacheData {
+  std::string token_name;
+  std::string token;
+  base::Time expiration_time;
+};
+
+// TODO: Should I put this in a namespace?  Which one?

[dcheng, 2013/03/04 22:40:59]

I'm not sure that "api/token_cache" is an appropriate place for this file, since
it's not implementing an extension API for token_cache. For now, you could try
putting it c/b/extensions. In that case, it should be in the extensions
namespace.

[Pete Williamson, 2013/03/05 19:42:25]

Done.

+
+class TokenCacheService : public ProfileKeyedService,
+    content::NotificationObserver {
+

[dcheng, 2013/03/04 22:40:59]

Extra newline.

[Pete Williamson, 2013/03/05 19:42:25]

Done.

+ public:
+  explicit TokenCacheService(Profile* profile);
+  virtual ~TokenCacheService();
+
+  // Store a token for the currently logged in user. We will look it up later by
+  // the name given here, and we will expire the token after the timeout.  For a
+  // timeout of 0, we never expire the token.  After time_to_live expires, the
+  // token will be expired.
+  void StoreToken(const std::string& token_name, const std::string& token_value,
+                  const base::TimeDelta time_to_live);

[dcheng, 2013/03/04 22:40:59]

No const.

[Pete Williamson, 2013/03/05 19:42:25]

Done.

+
+  // Retrieve a token for the currently logged in user.  This returns an empty
+  // string if the token was not found or timed out.
+  std::string RetrieveToken(const std::string& token_name);
+
+  std::vector<TokenCacheData>::iterator FindMatch(
+      const std::string& token_name);
+
+  // inherited from ProfileKeyedService
+  virtual void Shutdown() OVERRIDE;
+
+  // inherited from NotificationObserver
+  virtual void Observe(int type,
+                       const content::NotificationSource& source,
+                       const content::NotificationDetails& details) OVERRIDE;
+
+ private:
+  // TODO(petewil): If we start putting lots of tokens in here, use a map
+  // instead because the lookup time is O(n).
+  std::vector<TokenCacheData> token_cache_;
+  content::NotificationRegistrar registrar_;
+  const Profile* profile_;
+
+  friend class TokenCacheTest;
+
+  DISALLOW_COPY_AND_ASSIGN(TokenCacheService);
+};
+
+#endif  // CHROME_BROWSER_EXTENSIONS_API_TOKEN_CACHE_TOKEN_CACHE_H_