Write out CacheStorageCache size to index file.

content/browser/cache_storage/cache_storage.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_CACHE_STORAGE_CACHE_STORAGE_H_
 #define CONTENT_BROWSER_CACHE_STORAGE_CACHE_STORAGE_H_
 
 #include <stdint.h>
 
 #include <map>
 #include <memory>
 #include <string>
 #include <vector>
 
 #include "base/callback.h"
 #include "base/files/file_path.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
 #include "content/browser/cache_storage/cache_storage_cache.h"
+#include "content/browser/cache_storage/cache_storage_cache_observer.h"
 
 namespace base {
 class SequencedTaskRunner;
 }
 
 namespace net {
 class URLRequestContextGetter;
 }
 
 namespace storage {
 class BlobStorageContext;
 }
 
 namespace content {
 class CacheStorageCacheHandle;
+class CacheStorageIndex;
 class CacheStorageScheduler;
 
 // TODO(jkarlin): Constrain the total bytes used per origin.
 
 // CacheStorage holds the set of caches for a given origin. It is
 // owned by the CacheStorageManager. This class expects to be run
 // on the IO thread. The asynchronous methods are executed serially.
-class CONTENT_EXPORT CacheStorage {
+class CONTENT_EXPORT CacheStorage : public CacheStorageCacheObserver {
  public:
-  typedef std::vector<std::string> StringVector;
+  constexpr static int64_t kSizeUnknown = -1;
+
   typedef base::Callback<void(bool, CacheStorageError)> BoolAndErrorCallback;
   typedef base::Callback<void(std::unique_ptr<CacheStorageCacheHandle>,
                               CacheStorageError)>
       CacheAndErrorCallback;
-  using StringsCallback = base::Callback<void(const StringVector&)>;
+  using IndexCallback = base::Callback<void(const CacheStorageIndex&)>;
   using SizeCallback = base::Callback<void(int64_t)>;
 
   static const char kIndexFileName[];
 
   CacheStorage(
       const base::FilePath& origin_path,
       bool memory_only,
       base::SequencedTaskRunner* cache_task_runner,
       scoped_refptr<net::URLRequestContextGetter> request_context_getter,
       scoped_refptr<storage::QuotaManagerProxy> quota_manager_proxy,
@@ skipping 18 matching lines @@
 
   // Deletes the cache if it exists. If it doesn't exist,
   // CACHE_STORAGE_ERROR_NOT_FOUND is returned. Any existing
   // CacheStorageCacheHandle(s) to the cache will remain valid but future
   // CacheStorage operations won't be able to access the cache. The cache
   // isn't actually erased from disk until the last handle is dropped.
   // TODO(jkarlin): Rename to DoomCache.
   void DeleteCache(const std::string& cache_name,
                    const BoolAndErrorCallback& callback);
 
-  // Calls the callback with a vector of cache names (keys) available.
-  void EnumerateCaches(const StringsCallback& callback);
+  // Calls the callback with the cache index.
+  void EnumerateCaches(const IndexCallback& callback);
 
   // Calls match on the cache with the given |cache_name|.
   void MatchCache(const std::string& cache_name,
                   std::unique_ptr<ServiceWorkerFetchRequest> request,
                   const CacheStorageCacheQueryParams& match_params,
                   const CacheStorageCache::ResponseCallback& callback);
 
   // Calls match on all of the caches in parallel, calling |callback| with the
   // response from the first cache (in order of cache creation) to have the
   // entry. If no response is found then |callback| is called with
   // CACHE_STORAGE_ERROR_NOT_FOUND.
   void MatchAllCaches(std::unique_ptr<ServiceWorkerFetchRequest> request,
                       const CacheStorageCacheQueryParams& match_params,
                       const CacheStorageCache::ResponseCallback& callback);
 
   // Sums the sizes of each cache and closes them. Runs |callback| with the
   // size.
   void GetSizeThenCloseAllCaches(const SizeCallback& callback);
 
   // The size of all of the origin's contents. This value should be used as an
   // estimate only since the cache may be modified at any time.
   void Size(const SizeCallback& callback);
 
   // The functions below are for tests to verify that the operations run
   // serially.
   void StartAsyncOperationForTesting();
   void CompleteAsyncOperationForTesting();
 
+  // CacheStorageCacheObserver:
+  void CacheSizeUpdated(const CacheStorageCache* cache, int64_t size) override;
+
  private:
   friend class CacheStorageCacheHandle;
   friend class CacheStorageCache;
+  friend class CacheStorageManagerTest;
   class CacheLoader;
   class MemoryLoader;
   class SimpleCacheLoader;
   struct CacheMatchResponse;
 
   typedef std::map<std::string, std::unique_ptr<CacheStorageCache>> CacheMap;
 
   // Functions for exposing handles to CacheStorageCache to clients.
   std::unique_ptr<CacheStorageCacheHandle> CreateCacheHandle(
       CacheStorageCache* cache);
   void AddCacheHandleRef(CacheStorageCache* cache);
   void DropCacheHandleRef(CacheStorageCache* cache);
 
   // Returns a CacheStorageCacheHandle for the given name if the name is known.
   // If the CacheStorageCache has been deleted, creates a new one.
   std::unique_ptr<CacheStorageCacheHandle> GetLoadedCache(
       const std::string& cache_name);
 
   // Initializer and its callback are below.
   void LazyInit();
   void LazyInitImpl();
-  void LazyInitDidLoadIndex(
-      std::unique_ptr<std::vector<std::string>> indexed_cache_names);
+  void LazyInitDidLoadIndex(std::unique_ptr<CacheStorageIndex> index);
 
   // The Open and CreateCache callbacks are below.
   void OpenCacheImpl(const std::string& cache_name,
                      const CacheAndErrorCallback& callback);
   void CreateCacheDidCreateCache(const std::string& cache_name,
                                  const CacheAndErrorCallback& callback,
                                  std::unique_ptr<CacheStorageCache> cache);
   void CreateCacheDidWriteIndex(
       const CacheAndErrorCallback& callback,
       std::unique_ptr<CacheStorageCacheHandle> cache_handle,
       bool success);
 
   // The HasCache callbacks are below.
   void HasCacheImpl(const std::string& cache_name,
                     const BoolAndErrorCallback& callback);
 
   // The DeleteCache callbacks are below.
   void DeleteCacheImpl(const std::string& cache_name,
                        const BoolAndErrorCallback& callback);
   void DeleteCacheDidWriteIndex(
-      const std::string& cache_name,
-      const StringVector& original_ordered_cache_names,
+      std::unique_ptr<CacheStorageCacheHandle> cache_handle,
       const BoolAndErrorCallback& callback,
       bool success);
   void DeleteCacheFinalize(std::unique_ptr<CacheStorageCache> doomed_cache);
   void DeleteCacheDidGetSize(std::unique_ptr<CacheStorageCache> cache,
                              int64_t cache_size);
   void DeleteCacheDidCleanUp(bool success);
 
   // The EnumerateCache callbacks are below.
-  void EnumerateCachesImpl(const StringsCallback& callback);
+  void EnumerateCachesImpl(const IndexCallback& callback);
 
   // The MatchCache callbacks are below.
   void MatchCacheImpl(const std::string& cache_name,
                       std::unique_ptr<ServiceWorkerFetchRequest> request,
                       const CacheStorageCacheQueryParams& match_params,
                       const CacheStorageCache::ResponseCallback& callback);
   void MatchCacheDidMatch(std::unique_ptr<CacheStorageCacheHandle> cache_handle,
                           const CacheStorageCache::ResponseCallback& callback,
                           CacheStorageError error,
                           std::unique_ptr<ServiceWorkerResponse> response,
@@ skipping 10 matching lines @@
       CacheStorageError error,
       std::unique_ptr<ServiceWorkerResponse> service_worker_response,
       std::unique_ptr<storage::BlobDataHandle> handle);
   void MatchAllCachesDidMatchAll(
       std::unique_ptr<std::vector<CacheMatchResponse>> match_responses,
       const CacheStorageCache::ResponseCallback& callback);
 
   void GetSizeThenCloseAllCachesImpl(const SizeCallback& callback);
 
   void SizeImpl(const SizeCallback& callback);
+  void SizeRetrievedFromCache(
+      std::unique_ptr<CacheStorageCacheHandle> cache_handle,
+      const base::Closure& closure,
+      int64_t* accumulator,
+      int64_t size);
+
+  void DelayedScheduleWriteIndex();
+  void ScheduleWriteIndex();
+  void WriteIndex(const base::Callback<void(bool)>& callback);

[jkarlin, 2016/12/19 17:48:15]

The naming convention for this directory has been for the operation to have one
name, and the method that actually runs it to be Impl.

So in this case:

ScheduleWriteIndex -- posts the 5 second callback
WriteIndex -- schedules the operation
WriteIndexImpl -- does the actual work

[cmumford, 2016/12/19 19:25:57]

Done.

+  bool index_write_pending() const { return !index_write_task_.IsCancelled(); }
+  // Start a scheduled index write immediately. Returns true if a write was
+  // scheduled, or false if not.
+  bool InitiateScheduledIndexWriteForTest();
 
   // Whether or not we've loaded the list of cache names into memory.
   bool initialized_;
   bool initializing_;
 
   // True if the backend is supposed to reside in memory only.
   bool memory_only_;
 
   // The pending operation scheduler.
   std::unique_ptr<CacheStorageScheduler> scheduler_;
 
   // The map of cache names to CacheStorageCache objects.
   CacheMap cache_map_;
 
   // Caches that have been deleted but must still be held onto until all handles
   // have been released.
   std::map<CacheStorageCache*, std::unique_ptr<CacheStorageCache>>
       doomed_caches_;
 
   // CacheStorageCacheHandle reference counts
   std::map<CacheStorageCache*, size_t> cache_handle_counts_;
 
-  // The names of caches in the order that they were created.
-  StringVector ordered_cache_names_;
+  // The cache index data.
+  std::unique_ptr<CacheStorageIndex> cache_index_;
 
   // The file path for this CacheStorage.
   base::FilePath origin_path_;
 
   // The TaskRunner to run file IO on.
   scoped_refptr<base::SequencedTaskRunner> cache_task_runner_;
 
   // Performs backend specific operations (memory vs disk).
   std::unique_ptr<CacheLoader> cache_loader_;
 
   // The quota manager.
   scoped_refptr<storage::QuotaManagerProxy> quota_manager_proxy_;
 
   // The origin that this CacheStorage is associated with.
   GURL origin_;
 
+  base::CancelableClosure index_write_task_;
+
   base::WeakPtrFactory<CacheStorage> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(CacheStorage);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_CACHE_STORAGE_CACHE_STORAGE_H_