1// Copyright (c) 2012 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// HttpStreamBase is an interface for reading and writing data to an
6// HTTP-like stream that keeps the client agnostic of the actual underlying
7// transport layer.  This provides an abstraction for HttpStream and
8// WebSocketHandshakeStreamBase.
9
10#ifndef NET_HTTP_HTTP_STREAM_BASE_H_
11#define NET_HTTP_HTTP_STREAM_BASE_H_
12
13#include <string>
14
15#include "base/basictypes.h"
16#include "base/memory/scoped_ptr.h"
17#include "net/base/completion_callback.h"
18#include "net/base/net_export.h"
19#include "net/base/request_priority.h"
20#include "net/base/upload_progress.h"
21
22namespace net {
23
24class BoundNetLog;
25class HttpNetworkSession;
26class HttpRequestHeaders;
27struct HttpRequestInfo;
28class HttpResponseInfo;
29class IOBuffer;
30struct LoadTimingInfo;
31class SSLCertRequestInfo;
32class SSLInfo;
33
34class NET_EXPORT_PRIVATE HttpStreamBase {
35 public:
36  HttpStreamBase() {}
37  virtual ~HttpStreamBase() {}
38
39  // Initialize stream.  Must be called before calling SendRequest().
40  // |request_info| must outlive the HttpStreamBase.
41  // Returns a net error code, possibly ERR_IO_PENDING.
42  virtual int InitializeStream(const HttpRequestInfo* request_info,
43                               RequestPriority priority,
44                               const BoundNetLog& net_log,
45                               const CompletionCallback& callback) = 0;
46
47  // Writes the headers and uploads body data to the underlying socket.
48  // ERR_IO_PENDING is returned if the operation could not be completed
49  // synchronously, in which case the result will be passed to the callback
50  // when available. Returns OK on success.
51  //
52  // The callback will only be invoked once the first full set of headers have
53  // been received, at which point |response| will have been populated with that
54  // set of headers, and is safe to read, until/unless ReadResponseHeaders is
55  // called.
56  //
57  // |response| must remain valid until all sets of headers has been read, or
58  // the HttpStreamBase is destroyed. There's typically only one set of
59  // headers, except in the case of 1xx responses (See ReadResponseHeaders).
60  virtual int SendRequest(const HttpRequestHeaders& request_headers,
61                          HttpResponseInfo* response,
62                          const CompletionCallback& callback) = 0;
63
64  // Reads from the underlying socket until the next set of response headers
65  // have been completely received.  This may only be called on 1xx responses
66  // after SendRequest has completed successfully, to read the next set of
67  // headers.
68  //
69  // ERR_IO_PENDING is returned if the operation could not be completed
70  // synchronously, in which case the result will be passed to the callback when
71  // available. Returns OK on success. The response headers are available in
72  // the HttpResponseInfo passed in to original call to SendRequest.
73  virtual int ReadResponseHeaders(const CompletionCallback& callback) = 0;
74
75  // Reads response body data, up to |buf_len| bytes. |buf_len| should be a
76  // reasonable size (<2MB). The number of bytes read is returned, or an
77  // error is returned upon failure.  0 indicates that the request has been
78  // fully satisfied and there is no more data to read.
79  // ERR_CONNECTION_CLOSED is returned when the connection has been closed
80  // prematurely.  ERR_IO_PENDING is returned if the operation could not be
81  // completed synchronously, in which case the result will be passed to the
82  // callback when available. If the operation is not completed immediately,
83  // the socket acquires a reference to the provided buffer until the callback
84  // is invoked or the socket is destroyed.
85  virtual int ReadResponseBody(IOBuffer* buf, int buf_len,
86                               const CompletionCallback& callback) = 0;
87
88  // Closes the stream.
89  // |not_reusable| indicates if the stream can be used for further requests.
90  // In the case of HTTP, where we re-use the byte-stream (e.g. the connection)
91  // this means we need to close the connection; in the case of SPDY, where the
92  // underlying stream is never reused, it has no effect.
93  // TODO(mbelshe): We should figure out how to fold the not_reusable flag
94  //                into the stream implementation itself so that the caller
95  //                does not need to pass it at all.  We might also be able to
96  //                eliminate the SetConnectionReused() below.
97  virtual void Close(bool not_reusable) = 0;
98
99  // Indicates if the response body has been completely read.
100  virtual bool IsResponseBodyComplete() const = 0;
101
102  // Indicates that the end of the response is detectable. This means that
103  // the response headers indicate either chunked encoding or content length.
104  // If neither is sent, the server must close the connection for us to detect
105  // the end of the response.
106  // TODO(rch): Rename this method, so that it is clear why it exists
107  // particularly as it applies to QUIC and SPDY for which the end of the
108  // response is always findable.
109  virtual bool CanFindEndOfResponse() const = 0;
110
111  // A stream exists on top of a connection.  If the connection has been used
112  // to successfully exchange data in the past, error handling for the
113  // stream is done differently.  This method returns true if the underlying
114  // connection is reused or has been connected and idle for some time.
115  virtual bool IsConnectionReused() const = 0;
116  virtual void SetConnectionReused() = 0;
117
118  // Checks whether the current state of the underlying connection
119  // allows it to be reused.
120  virtual bool IsConnectionReusable() const = 0;
121
122  // Get the total number of bytes received from network for this stream.
123  virtual int64 GetTotalReceivedBytes() const = 0;
124
125  // Populates the connection establishment part of |load_timing_info|, and
126  // socket ID.  |load_timing_info| must have all null times when called.
127  // Returns false and does nothing if there is no underlying connection, either
128  // because one has yet to be assigned to the stream, or because the underlying
129  // socket has been closed.
130  //
131  // In practice, this means that this function will always succeed any time
132  // between when the full headers have been received and the stream has been
133  // closed.
134  virtual bool GetLoadTimingInfo(LoadTimingInfo* load_timing_info) const = 0;
135
136  // Get the SSLInfo associated with this stream's connection.  This should
137  // only be called for streams over SSL sockets, otherwise the behavior is
138  // undefined.
139  virtual void GetSSLInfo(SSLInfo* ssl_info) = 0;
140
141  // Get the SSLCertRequestInfo associated with this stream's connection.
142  // This should only be called for streams over SSL sockets, otherwise the
143  // behavior is undefined.
144  virtual void GetSSLCertRequestInfo(SSLCertRequestInfo* cert_request_info) = 0;
145
146  // HACK(willchan): Really, we should move the HttpResponseDrainer logic into
147  // the HttpStream implementation. This is just a quick hack.
148  virtual bool IsSpdyHttpStream() const = 0;
149
150  // In the case of an HTTP error or redirect, flush the response body (usually
151  // a simple error or "this page has moved") so that we can re-use the
152  // underlying connection. This stream is responsible for deleting itself when
153  // draining is complete.
154  virtual void Drain(HttpNetworkSession* session) = 0;
155
156  // Called when the priority of the parent transaction changes.
157  virtual void SetPriority(RequestPriority priority) = 0;
158
159 private:
160  DISALLOW_COPY_AND_ASSIGN(HttpStreamBase);
161};
162
163}  // namespace net
164
165#endif  // NET_HTTP_HTTP_STREAM_BASE_H_
166