1// Copyright 2014 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#ifndef COMPONENTS_COMPONENT_UPDATER_REQUEST_SENDER_H_
6#define COMPONENTS_COMPONENT_UPDATER_REQUEST_SENDER_H_
7
8#include <string>
9#include <vector>
10
11#include "base/callback.h"
12#include "base/compiler_specific.h"
13#include "base/macros.h"
14#include "base/memory/scoped_ptr.h"
15#include "base/threading/thread_checker.h"
16#include "net/url_request/url_fetcher_delegate.h"
17#include "url/gurl.h"
18
19namespace net {
20class URLFetcher;
21}
22
23namespace component_updater {
24
25class Configurator;
26
27// Sends a request to one of the urls provided. The class implements a chain
28// of responsibility design pattern, where the urls are tried in the order they
29// are specified, until the request to one of them succeeds or all have failed.
30class RequestSender : public net::URLFetcherDelegate {
31 public:
32  // The |source| refers to the fetcher object used to make the request. This
33  // parameter can be NULL in some error cases.
34  typedef base::Callback<void(const net::URLFetcher* source)>
35      RequestSenderCallback;
36
37  explicit RequestSender(const Configurator& config);
38  virtual ~RequestSender();
39
40  void Send(const std::string& request_string,
41            const std::vector<GURL>& urls,
42            const RequestSenderCallback& request_sender_callback);
43
44 private:
45  void SendInternal();
46
47  // Overrides for URLFetcherDelegate.
48  virtual void OnURLFetchComplete(const net::URLFetcher* source) OVERRIDE;
49
50  const Configurator& config_;
51  std::vector<GURL> urls_;
52  std::vector<GURL>::const_iterator cur_url_;
53  scoped_ptr<net::URLFetcher> url_fetcher_;
54  std::string request_string_;
55  RequestSenderCallback request_sender_callback_;
56
57  base::ThreadChecker thread_checker_;
58
59  DISALLOW_COPY_AND_ASSIGN(RequestSender);
60};
61
62}  // namespace component_updater
63
64#endif  // COMPONENTS_COMPONENT_UPDATER_REQUEST_SENDER_H_
65