components/translate/core/browser/translate_url_fetcher.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 COMPONENTS_TRANSLATE_CORE_BROWSER_TRANSLATE_URL_FETCHER_H_
   6 #define COMPONENTS_TRANSLATE_CORE_BROWSER_TRANSLATE_URL_FETCHER_H_
   7
   8 #include "base/callback.h"
   9 #include "base/memory/scoped_ptr.h"
  10 #include "net/url_request/url_fetcher_delegate.h"
  11 #include "url/gurl.h"
  12
  13 namespace translate {
  14
  15 // Downloads raw Translate data such as the Translate script and the language
  16 // list.
  17 class TranslateURLFetcher : public net::URLFetcherDelegate {
  18  public:
  19   // Callback type for Request().
  20   typedef base::Callback<void(int, bool, const std::string&)> Callback;
  21
  22   // Represents internal state if the fetch is completed successfully.
  23   enum State {
  24     IDLE,        // No fetch request was issued.
  25     REQUESTING,  // A fetch request was issued, but not finished yet.
  26     COMPLETED,   // The last fetch request was finished successfully.
  27     FAILED,      // The last fetch request was finished with a failure.
  28   };
  29
  30   explicit TranslateURLFetcher(int id);
  31   virtual ~TranslateURLFetcher();
  32
  33   int max_retry_on_5xx() {
  34     return max_retry_on_5xx_;
  35   }
  36   void set_max_retry_on_5xx(int count) {
  37     max_retry_on_5xx_ = count;
  38   }
  39
  40   const std::string& extra_request_header() {
  41     return extra_request_header_;
  42   }
  43   void set_extra_request_header(const std::string& header) {
  44     extra_request_header_ = header;
  45   }
  46
  47   // Requests to |url|. |callback| will be invoked when the function returns
  48   // true, and the request is finished asynchronously.
  49   // Returns false if the previous request is not finished, or the request
  50   // is omitted due to retry limitation.
  51   bool Request(const GURL& url, const Callback& callback);
  52
  53   // Gets internal state.
  54   State state() { return state_; }
  55
  56   // net::URLFetcherDelegate implementation:
  57   virtual void OnURLFetchComplete(const net::URLFetcher* source) override;
  58
  59  private:
  60   // URL to send the request.
  61   GURL url_;
  62
  63   // ID which is assigned to the URLFetcher.
  64   const int id_;
  65
  66   // Internal state.
  67   enum State state_;
  68
  69   // URLFetcher instance.
  70   scoped_ptr<net::URLFetcher> fetcher_;
  71
  72   // Callback passed at Request(). It will be invoked when an asynchronous
  73   // fetch operation is finished.
  74   Callback callback_;
  75
  76   // Counts how many times did it try to fetch the language list.
  77   int retry_count_;
  78
  79   // Max number how many times to retry on the server error
  80   int max_retry_on_5xx_;
  81
  82   // An extra HTTP request header
  83   std::string extra_request_header_;
  84
  85   DISALLOW_COPY_AND_ASSIGN(TranslateURLFetcher);
  86 };
  87
  88 }  // namespace translate
  89
  90 #endif  // COMPONENTS_TRANSLATE_CORE_BROWSER_TRANSLATE_URL_FETCHER_H_