| // Copyright 2014 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_UPDATE_CLIENT_REQUEST_SENDER_H_ |
| #define COMPONENTS_UPDATE_CLIENT_REQUEST_SENDER_H_ |
| |
| #include <stdint.h> |
| |
| #include <memory> |
| #include <string> |
| #include <vector> |
| |
| #include "base/callback.h" |
| #include "base/macros.h" |
| #include "base/memory/ref_counted.h" |
| #include "base/threading/thread_checker.h" |
| #include "net/url_request/url_fetcher_delegate.h" |
| #include "url/gurl.h" |
| |
| namespace client_update_protocol { |
| class Ecdsa; |
| } |
| |
| namespace net { |
| class URLFetcher; |
| } |
| |
| namespace update_client { |
| |
| class Configurator; |
| |
| // Sends a request to one of the urls provided. The class implements a chain |
| // of responsibility design pattern, where the urls are tried in the order they |
| // are specified, until the request to one of them succeeds or all have failed. |
| // CUP signing is optional. |
| class RequestSender : public net::URLFetcherDelegate { |
| public: |
| // If |error| is 0, then the response is provided in the |response| parameter. |
| // |retry_after_sec| contains the value of the X-Retry-After response header, |
| // when the response was received from a cryptographically secure URL. The |
| // range for this value is [-1, 86400]. If |retry_after_sec| is -1 it means |
| // that the header could not be found, or trusted, or had an invalid value. |
| // The upper bound represents a delay of one day. |
| using RequestSenderCallback = base::OnceCallback< |
| void(int error, const std::string& response, int retry_after_sec)>; |
| |
| // This value is chosen not to conflict with network errors defined by |
| // net/base/net_error_list.h. The callers don't have to handle this error in |
| // any meaningful way, but this value may be reported in UMA stats, therefore |
| // avoiding collisions with known network errors is desirable. |
| enum : int { kErrorResponseNotTrusted = -10000 }; |
| |
| explicit RequestSender(const scoped_refptr<Configurator>& config); |
| ~RequestSender() override; |
| |
| // |use_signing| enables CUP signing of protocol messages exchanged using |
| // this class. |
| void Send(bool use_signing, |
| const std::string& request_body, |
| const std::vector<GURL>& urls, |
| RequestSenderCallback request_sender_callback); |
| |
| private: |
| // Combines the |url| and |query_params| parameters. |
| static GURL BuildUpdateUrl(const GURL& url, const std::string& query_params); |
| |
| // Decodes and returns the public key used by CUP. |
| static std::string GetKey(const char* key_bytes_base64); |
| |
| // Returns the string value of a header of the server response or an empty |
| // string if the header is not available. |
| static std::string GetStringHeaderValue(const net::URLFetcher* source, |
| const char* header_name); |
| |
| // Returns the integral value of a header of the server response or -1 if |
| // if the header is not available or a conversion error has occured. |
| static int64_t GetInt64HeaderValue(const net::URLFetcher* source, |
| const char* header_name); |
| |
| // Overrides for URLFetcherDelegate. |
| void OnURLFetchComplete(const net::URLFetcher* source) override; |
| |
| // Implements the error handling and url fallback mechanism. |
| void SendInternal(); |
| |
| // Called when SendInternal completes. |response_body| and |response_etag| |
| // contain the body and the etag associated with the HTTP response. |
| void SendInternalComplete(int error, |
| const std::string& response_body, |
| const std::string& response_etag, |
| int retry_after_sec); |
| |
| // Helper function to handle a non-continuable error in Send. |
| void HandleSendError(int error, int retry_after_sec); |
| |
| base::ThreadChecker thread_checker_; |
| |
| const scoped_refptr<Configurator> config_; |
| bool use_signing_; // True if CUP signing is used. |
| std::vector<GURL> urls_; |
| std::string request_body_; |
| RequestSenderCallback request_sender_callback_; |
| |
| std::string public_key_; |
| std::vector<GURL>::const_iterator cur_url_; |
| std::unique_ptr<net::URLFetcher> url_fetcher_; |
| std::unique_ptr<client_update_protocol::Ecdsa> signer_; |
| |
| DISALLOW_COPY_AND_ASSIGN(RequestSender); |
| }; |
| |
| } // namespace update_client |
| |
| #endif // COMPONENTS_UPDATE_CLIENT_REQUEST_SENDER_H_ |