[rac] Temporarily copy libaddressinput to Chrome.

third_party/libaddressinput/chromium/cpp/src/retriever.h

+// Copyright (C) 2013 Google Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// An object to retrieve data.
+
+#ifndef I18N_ADDRESSINPUT_RETRIEVER_H_
+#define I18N_ADDRESSINPUT_RETRIEVER_H_
+
+#include <libaddressinput/callback.h>
+#include <libaddressinput/util/basictypes.h>
+#include <libaddressinput/util/scoped_ptr.h>
+
+#include <string>
+
+#include "lookup_key_util.h"
+
+namespace i18n {
+namespace addressinput {
+
+class Downloader;
+class Storage;
+
+// Retrieves data. Sample usage:
+//    Storage* storage = ...;
+//    Downloader* downloader = ...;
+//    Retriever retriever("https://i18napis.appspot.com/ssl-address/",
+//                        downloader, storage);
+//    scoped_ptr<Retriever::Callback> retrieved(BuildCallback(
+//        this, &MyClass::OnDataRetrieved));
+//    retriever.Retrieve("data/CA/AB--fr", *retrieved);
+class Retriever {
+ public:
+  typedef i18n::addressinput::Callback<std::string, std::string> Callback;
+
+  // Takes ownership of |downloader| and |storage|.
+  Retriever(const std::string& validation_data_url,
+            const Downloader* downloader,
+            Storage* storage);
+  ~Retriever();
+
+  // Retrieves the data for |key| and invokes the |retrieved| callback. Checks
+  // for the data in storage first. If storage does not have the data for |key|,
+  // then downloads the data and places it in storage.
+  void Retrieve(const std::string& key, const Callback& retrieved) const;
+
+ private:
+  const LookupKeyUtil lookup_key_util_;
+  scoped_ptr<const Downloader> downloader_;
+  scoped_ptr<Storage> storage_;
+
+  DISALLOW_COPY_AND_ASSIGN(Retriever);
+};
+
+}  // namespace addressinput
+}  // namespace i18n
+
+#endif  // I18N_ADDRESSINPUT_RETRIEVER_H_