net/http/http_transaction.h

   1 // Copyright (c) 2011 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 NET_HTTP_HTTP_TRANSACTION_H_
   6 #define NET_HTTP_HTTP_TRANSACTION_H_
   7
   8 #include "net/base/completion_callback.h"
   9 #include "net/base/load_states.h"
  10 #include "net/base/net_export.h"
  11 #include "net/base/request_priority.h"
  12 #include "net/base/upload_progress.h"
  13 #include "net/socket/connection_attempts.h"
  14 #include "net/websockets/websocket_handshake_stream_base.h"
  15
  16 namespace net {
  17
  18 class AuthCredentials;
  19 class BoundNetLog;
  20 class HttpRequestHeaders;
  21 struct HttpRequestInfo;
  22 class HttpResponseInfo;
  23 class IOBuffer;
  24 struct LoadTimingInfo;
  25 class ProxyInfo;
  26 class QuicServerInfo;
  27 class X509Certificate;
  28
  29 // Represents a single HTTP transaction (i.e., a single request/response pair).
  30 // HTTP redirects are not followed and authentication challenges are not
  31 // answered.  Cookies are assumed to be managed by the caller.
  32 class NET_EXPORT_PRIVATE HttpTransaction {
  33  public:
  34   // If |*defer| is set to true, the transaction will wait until
  35   // ResumeNetworkStart is called before establishing a connection.
  36   typedef base::Callback<void(bool* defer)> BeforeNetworkStartCallback;
  37
  38   // Provides an opportunity to add proxy-specific request headers. Called after
  39   // it is determined that a proxy is being used and before the request headers
  40   // are sent. |proxy_info| contains information about the proxy being used,
  41   // and additional headers may be added to |request_headers|.
  42   typedef base::Callback<void(
  43       const ProxyInfo& proxy_info,
  44       HttpRequestHeaders* request_headers)> BeforeProxyHeadersSentCallback;
  45
  46   // Stops any pending IO and destroys the transaction object.
  47   virtual ~HttpTransaction() {}
  48
  49   // Starts the HTTP transaction (i.e., sends the HTTP request).
  50   //
  51   // Returns OK if the transaction could be started synchronously, which means
  52   // that the request was served from the cache.  ERR_IO_PENDING is returned to
  53   // indicate that the CompletionCallback will be notified once response info is
  54   // available or if an IO error occurs.  Any other return value indicates that
  55   // the transaction could not be started.
  56   //
  57   // Regardless of the return value, the caller is expected to keep the
  58   // request_info object alive until Destroy is called on the transaction.
  59   //
  60   // NOTE: The transaction is not responsible for deleting the callback object.
  61   //
  62   // Profiling information for the request is saved to |net_log| if non-NULL.
  63   virtual int Start(const HttpRequestInfo* request_info,
  64                     const CompletionCallback& callback,
  65                     const BoundNetLog& net_log) = 0;
  66
  67   // Restarts the HTTP transaction, ignoring the last error.  This call can
  68   // only be made after a call to Start (or RestartIgnoringLastError) failed.
  69   // Once Read has been called, this method cannot be called.  This method is
  70   // used, for example, to continue past various SSL related errors.
  71   //
  72   // Not all errors can be ignored using this method.  See error code
  73   // descriptions for details about errors that can be ignored.
  74   //
  75   // NOTE: The transaction is not responsible for deleting the callback object.
  76   //
  77   virtual int RestartIgnoringLastError(const CompletionCallback& callback) = 0;
  78
  79   // Restarts the HTTP transaction with a client certificate.
  80   virtual int RestartWithCertificate(X509Certificate* client_cert,
  81                                      const CompletionCallback& callback) = 0;
  82
  83   // Restarts the HTTP transaction with authentication credentials.
  84   virtual int RestartWithAuth(const AuthCredentials& credentials,
  85                               const CompletionCallback& callback) = 0;
  86
  87   // Returns true if auth is ready to be continued. Callers should check
  88   // this value anytime Start() completes: if it is true, the transaction
  89   // can be resumed with RestartWithAuth(L"", L"", callback) to resume
  90   // the automatic auth exchange. This notification gives the caller a
  91   // chance to process the response headers from all of the intermediate
  92   // restarts needed for authentication.
  93   virtual bool IsReadyToRestartForAuth() = 0;
  94
  95   // Once response info is available for the transaction, response data may be
  96   // read by calling this method.
  97   //
  98   // Response data is copied into the given buffer and the number of bytes
  99   // copied is returned.  ERR_IO_PENDING is returned if response data is not
 100   // yet available.  The CompletionCallback is notified when the data copy
 101   // completes, and it is passed the number of bytes that were successfully
 102   // copied.  Or, if a read error occurs, the CompletionCallback is notified of
 103   // the error.  Any other negative return value indicates that the transaction
 104   // could not be read.
 105   //
 106   // NOTE: The transaction is not responsible for deleting the callback object.
 107   // If the operation is not completed immediately, the transaction must acquire
 108   // a reference to the provided buffer.
 109   //
 110   virtual int Read(IOBuffer* buf, int buf_len,
 111                    const CompletionCallback& callback) = 0;
 112
 113   // Stops further caching of this request by the HTTP cache, if there is any.
 114   virtual void StopCaching() = 0;
 115
 116   // Gets the full request headers sent to the server.  This is guaranteed to
 117   // work only if Start returns success and the underlying transaction supports
 118   // it.  (Right now, this is only network transactions, not cache ones.)
 119   //
 120   // Returns true and overwrites headers if it can get the request headers;
 121   // otherwise, returns false and does not modify headers.
 122   virtual bool GetFullRequestHeaders(HttpRequestHeaders* headers) const = 0;
 123
 124   // Get the number of bytes received from network.
 125   virtual int64 GetTotalReceivedBytes() const = 0;
 126
 127   // Called to tell the transaction that we have successfully reached the end
 128   // of the stream. This is equivalent to performing an extra Read() at the end
 129   // that should return 0 bytes. This method should not be called if the
 130   // transaction is busy processing a previous operation (like a pending Read).
 131   //
 132   // DoneReading may also be called before the first Read() to notify that the
 133   // entire response body is to be ignored (e.g., in a redirect).
 134   virtual void DoneReading() = 0;
 135
 136   // Returns the response info for this transaction. Must not be called until
 137   // |Start| completes.
 138   virtual const HttpResponseInfo* GetResponseInfo() const = 0;
 139
 140   // Returns the load state for this transaction.
 141   virtual LoadState GetLoadState() const = 0;
 142
 143   // Returns the upload progress in bytes.  If there is no upload data,
 144   // zero will be returned.  This does not include the request headers.
 145   virtual UploadProgress GetUploadProgress() const = 0;
 146
 147   // SetQuicServerInfo sets a object which reads and writes public information
 148   // about a QUIC server.
 149   virtual void SetQuicServerInfo(QuicServerInfo* quic_server_info) = 0;
 150
 151   // Populates all of load timing, except for request start times and receive
 152   // headers time.
 153   // |load_timing_info| must have all null times when called.  Returns false and
 154   // does not modify |load_timing_info| if there's no timing information to
 155   // provide.
 156   virtual bool GetLoadTimingInfo(LoadTimingInfo* load_timing_info) const = 0;
 157
 158   // Called when the priority of the parent job changes.
 159   virtual void SetPriority(RequestPriority priority) = 0;
 160
 161   // Set the WebSocketHandshakeStreamBase::CreateHelper to be used for the
 162   // request.  Only relevant to WebSocket transactions. Must be called before
 163   // Start(). Ownership of |create_helper| remains with the caller.
 164   virtual void SetWebSocketHandshakeStreamCreateHelper(
 165       WebSocketHandshakeStreamBase::CreateHelper* create_helper) = 0;
 166
 167   // Set the callback to receive notification just before network use.
 168   virtual void SetBeforeNetworkStartCallback(
 169       const BeforeNetworkStartCallback& callback) = 0;
 170
 171   // Set the callback to receive notification just before a proxy request
 172   // is to be sent.
 173   virtual void SetBeforeProxyHeadersSentCallback(
 174       const BeforeProxyHeadersSentCallback& callback) = 0;
 175
 176   // Resumes the transaction after being deferred.
 177   virtual int ResumeNetworkStart() = 0;
 178
 179   virtual void GetConnectionAttempts(ConnectionAttempts* out) const = 0;
 180 };
 181
 182 }  // namespace net
 183
 184 #endif  // NET_HTTP_HTTP_TRANSACTION_H_