chromeos/timezone/timezone_request.h

   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 CHROMEOS_TIMEZONE_TIMEZONE_REQUEST_H_
   6 #define CHROMEOS_TIMEZONE_TIMEZONE_REQUEST_H_
   7
   8 #include "base/basictypes.h"
   9 #include "base/callback.h"
  10 #include "base/compiler_specific.h"
  11 #include "base/memory/ref_counted.h"
  12 #include "base/memory/scoped_ptr.h"
  13 #include "base/threading/thread_checker.h"
  14 #include "base/timer/timer.h"
  15 #include "chromeos/chromeos_export.h"
  16 #include "chromeos/geolocation/geoposition.h"
  17 #include "net/url_request/url_fetcher.h"
  18 #include "net/url_request/url_fetcher_delegate.h"
  19 #include "url/gurl.h"
  20
  21 namespace net {
  22 class URLRequestContextGetter;
  23 }
  24
  25 namespace chromeos {
  26
  27 struct CHROMEOS_EXPORT TimeZoneResponseData {
  28   enum Status {
  29     OK,
  30     INVALID_REQUEST,
  31     OVER_QUERY_LIMIT,
  32     REQUEST_DENIED,
  33     UNKNOWN_ERROR,
  34     ZERO_RESULTS,
  35     REQUEST_ERROR  // local problem
  36   };
  37
  38   TimeZoneResponseData();
  39
  40   std::string ToStringForDebug() const;
  41
  42   double dstOffset;
  43   double rawOffset;
  44   std::string timeZoneId;
  45   std::string timeZoneName;
  46   std::string error_message;
  47   Status status;
  48 };
  49
  50 // Returns default timezone service URL.
  51 CHROMEOS_EXPORT GURL DefaultTimezoneProviderURL();
  52
  53 // Takes Geoposition and sends it to a server to get local timezone information.
  54 // It performs formatting of the request and interpretation of the response.
  55 // If error occurs, request is retried until timeout.
  56 // Zero timeout indicates single request.
  57 // Request is owned and destroyed by caller (usually TimeZoneProvider).
  58 // If request is destroyed while callback has not beed called yet, request
  59 // is silently cancelled.
  60 class CHROMEOS_EXPORT TimeZoneRequest : private net::URLFetcherDelegate {
  61  public:
  62   // Called when a new geo timezone information is available.
  63   // The second argument indicates whether there was a server error or not.
  64   // It is true when there was a server or network error - either no response
  65   // or a 500 error code.
  66   typedef base::Callback<void(scoped_ptr<TimeZoneResponseData> /* timezone */,
  67                               bool /* server_error */)>
  68       TimeZoneResponseCallback;
  69
  70   // |url| is the server address to which the request wil be sent.
  71   // |geoposition| is the location to query timezone for.
  72   // |retry_timeout| retry request on error until timeout.
  73   TimeZoneRequest(net::URLRequestContextGetter* url_context_getter,
  74                   const GURL& service_url,
  75                   const Geoposition& geoposition,
  76                   base::TimeDelta retry_timeout);
  77
  78   ~TimeZoneRequest() override;
  79
  80   // Initiates request.
  81   // Note: if request object is destroyed before callback is called,
  82   // request will be silently cancelled.
  83   void MakeRequest(TimeZoneResponseCallback callback);
  84
  85   void set_retry_sleep_on_server_error_for_testing(
  86       const base::TimeDelta value) {
  87     retry_sleep_on_server_error_ = value;
  88   }
  89
  90   void set_retry_sleep_on_bad_response_for_testing(
  91       const base::TimeDelta value) {
  92     retry_sleep_on_bad_response_ = value;
  93   }
  94
  95  private:
  96   // net::URLFetcherDelegate
  97   void OnURLFetchComplete(const net::URLFetcher* source) override;
  98
  99   // Start new request.
 100   void StartRequest();
 101
 102   // Schedules retry.
 103   void Retry(bool server_error);
 104
 105   scoped_refptr<net::URLRequestContextGetter> url_context_getter_;
 106   const GURL service_url_;
 107   Geoposition geoposition_;
 108
 109   TimeZoneResponseCallback callback_;
 110
 111   GURL request_url_;
 112   scoped_ptr<net::URLFetcher> url_fetcher_;
 113
 114   // When request was actually started.
 115   base::Time request_started_at_;
 116
 117   // Absolute time, when it is passed no more retry requests are allowed.
 118   base::Time retry_timeout_abs_;
 119
 120   // Pending retry.
 121   base::OneShotTimer<TimeZoneRequest> timezone_request_scheduled_;
 122
 123   base::TimeDelta retry_sleep_on_server_error_;
 124
 125   base::TimeDelta retry_sleep_on_bad_response_;
 126
 127   // Number of retry attempts.
 128   unsigned retries_;
 129
 130   // Creation and destruction should happen on the same thread.
 131   base::ThreadChecker thread_checker_;
 132
 133   DISALLOW_COPY_AND_ASSIGN(TimeZoneRequest);
 134 };
 135
 136 }  // namespace chromeos
 137
 138 #endif  // CHROMEOS_TIMEZONE_TIMEZONE_REQUEST_H_