Fill in some of ServiceWorkerFetchStores.

content/browser/service_worker/service_worker_fetch_stores.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 CONTENT_BROWSER_SERVICE_WORKER_SERVICE_WORKER_FETCH_STORES_H_
 #define CONTENT_BROWSER_SERVICE_WORKER_SERVICE_WORKER_FETCH_STORES_H_
 
+#include <map>
 #include <string>
 
 #include "base/callback.h"
 #include "base/files/file_path.h"
+#include "base/id_map.h"
 #include "base/threading/thread_checker.h"
 
 namespace base {
 class MessageLoopProxy;
 }
 
 namespace content {
 
 class ServiceWorkerFetchStore;
 
 // The set of stores for a given ServiceWorker. It is owned by the

[michaeln, 2014/08/05 23:34:30]

s/b The set of stores for a given Origin.

[jkarlin, 2014/08/06 18:56:00]

Done.

 // ServiceWorkerFetchStoresManager. Provided callbacks are called on the
 // |callback_loop| provided in the constructor.
 class ServiceWorkerFetchStores {
  public:
   enum FetchStoresError {
     FETCH_STORES_ERROR_NO_ERROR,
     FETCH_STORES_ERROR_NOT_IMPLEMENTED,
     FETCH_STORES_ERROR_NOT_FOUND,
     FETCH_STORES_ERROR_EXISTS,
-    FETCH_STORES_ERROR_STORAGE
+    FETCH_STORES_ERROR_STORAGE,
+    FETCH_STORES_ERROR_EMPTY_KEY,
   };
 
-  enum BackendType { BACKEND_TYPE_SIMPLE_CACHE, BACKEND_TYPE_MEMORY };
-
   typedef base::Callback<void(bool, FetchStoresError)> BoolAndErrorCallback;
   typedef base::Callback<void(int, FetchStoresError)> StoreAndErrorCallback;
   typedef base::Callback<void(const std::vector<std::string>&,
                               FetchStoresError)> StringsAndErrorCallback;
 
   ServiceWorkerFetchStores(
       const base::FilePath& origin_path,
-      BackendType backend,
+      bool memory_only,
       const scoped_refptr<base::MessageLoopProxy>& callback_loop);
   virtual ~ServiceWorkerFetchStores();
 
+  // Create a ServiceWorkerFetchStore if it doesn't already exist and call the
+  // callback with the cache's id. If it already
+  // exists the callback is called with FETCH_STORES_ERROR_EXISTS.
   void CreateStore(const std::string& key,
                    const StoreAndErrorCallback& callback);
+
+  // Get the cache id for the given key.  If not found returns

[michaeln, 2014/08/05 23:34:30]

nit: extra space after the first sentence

[jkarlin, 2014/08/06 18:56:00]

Done.

+  // FETCH_STORES_ERROR_NOT_FOUND.
   void Get(const std::string& key, const StoreAndErrorCallback& callback);
-  void Has(const std::string& key, const BoolAndErrorCallback& callback) const;
-  void Delete(const std::string& key, const StoreAndErrorCallback& callback);
-  void Keys(const StringsAndErrorCallback& callback) const;
+
+  // Calls the callback with whether or not the cache exists.
+  void Has(const std::string& key, const BoolAndErrorCallback& callback);
+
+  // Deletes the cache if it exists. If it doesn't exist,
+  // FETCH_STORES_ERROR_NOT_FOUND is returned.
+  void Delete(const std::string& key, const BoolAndErrorCallback& callback);
+
+  // Calls the callback with a vector of cache names (keys) available.
+  void Keys(const StringsAndErrorCallback& callback);
+
   // TODO(jkarlin): Add match() function.
 
  private:
+  class MemoryLoader;
+  class SimpleCacheLoader;
+  class StoresLoader;
+
+  typedef IDMap<ServiceWorkerFetchStore, IDMapOwnPointer> StoreMap;
+  typedef StoreMap::KeyType StoreID;
+  typedef std::map<std::string, StoreID> NameMap;
+
+  ServiceWorkerFetchStore* GetLoadedStore(const std::string& key) const;
+
+  void LazyInit();
+  void InitStore(ServiceWorkerFetchStore* store);
+
+  StoreMap loaded_store_ids_;

[michaeln, 2014/08/05 23:34:30]

i think the name of this data member is misleading, i was surprised to see this
owned the ptrs to the store instances, the StoreMap type is accurate, maybe call
this store_map_

[jkarlin, 2014/08/06 18:56:00]

Done.

+  NameMap loaded_store_names_;
+  bool initialized_;
   base::FilePath origin_path_;
-  BackendType backend_type_;
   scoped_refptr<base::MessageLoopProxy> callback_loop_;
+  scoped_ptr<StoresLoader> stores_loader_;
 
   DISALLOW_COPY_AND_ASSIGN(ServiceWorkerFetchStores);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_SERVICE_WORKER_SERVICE_WORKER_FETCH_STORES_H_