[Offline pages] Adding capability to query a subset of requests based on IDs

components/offline_pages/background/request_queue_store_sql.h

 // Copyright 2016 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 COMPONENTS_OFFLINE_PAGES_BACKGROUND_REQUEST_QUEUE_STORE_SQL_H_
 #define COMPONENTS_OFFLINE_PAGES_BACKGROUND_REQUEST_QUEUE_STORE_SQL_H_
 
 #include <stdint.h>
 #include <memory>
 #include <vector>
@@ skipping 15 matching lines @@
 // SQLite implementation of RequestQueueStore.
 class RequestQueueStoreSQL : public RequestQueueStore {
  public:
   RequestQueueStoreSQL(
       scoped_refptr<base::SequencedTaskRunner> background_task_runner,
       const base::FilePath& database_dir);
   ~RequestQueueStoreSQL() override;
 
   // RequestQueueStore implementation.
   void GetRequests(const GetRequestsCallback& callback) override;
+  // Note: current implementation of this method makes a SQL query per ID. This
+  // is OK as long as number of IDs stays low, which is a typical case.
+  // Implementation should be revisited in case that presumption changes.
+  void GetRequestsByIds(const std::vector<int64_t>& request_ids,
+                        const UpdateCallback& callback) override;
   void AddRequest(const SavePageRequest& offline_page,
                   const AddCallback& callback) override;
   void UpdateRequests(const std::vector<SavePageRequest>& requests,
                       const UpdateCallback& callback) override;
   void RemoveRequests(const std::vector<int64_t>& request_ids,
                       const UpdateCallback& callback) override;
   void Reset(const ResetCallback& callback) override;
   StoreState state() const override;
 
  private:
@@ skipping 19 matching lines @@
   // State of the store.
   StoreState state_;
 
   base::WeakPtrFactory<RequestQueueStoreSQL> weak_ptr_factory_;
   DISALLOW_COPY_AND_ASSIGN(RequestQueueStoreSQL);
 };
 
 }  // namespace offline_pages
 
 #endif  // COMPONENTS_OFFLINE_PAGES_BACKGROUND_REQUEST_QUEUE_STORE_SQL_H_