1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
|
// Copyright (c) 2017 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.
#include "content/browser/appcache/appcache_update_url_fetcher.h"
#include "base/command_line.h"
#include "base/threading/thread_task_runner_handle.h"
#include "components/network_session_configurator/common/network_switches.h"
#include "content/browser/appcache/appcache_update_request_base.h"
#include "net/base/load_flags.h"
#include "net/http/http_request_headers.h"
#include "net/http/http_response_headers.h"
namespace content {
namespace {
const int kMax503Retries = 3;
} // namespace
// Helper class to fetch resources. Depending on the fetch type,
// can either fetch to an in-memory string or write the response
// data out to the disk cache.
AppCacheUpdateJob::URLFetcher::URLFetcher(const GURL& url,
FetchType fetch_type,
AppCacheUpdateJob* job,
int buffer_size)
: url_(url),
job_(job),
fetch_type_(fetch_type),
retry_503_attempts_(0),
request_(
UpdateRequestBase::Create(job->service_, url, buffer_size, this)),
result_(AppCacheUpdateJob::UPDATE_OK),
redirect_response_code_(-1),
buffer_size_(buffer_size) {}
AppCacheUpdateJob::URLFetcher::~URLFetcher() {}
void AppCacheUpdateJob::URLFetcher::Start() {
request_->SetSiteForCookies(job_->manifest_url_);
request_->SetInitiator(url::Origin::Create(job_->manifest_url_));
if (fetch_type_ == MANIFEST_FETCH && job_->doing_full_update_check_)
request_->SetLoadFlags(request_->GetLoadFlags() | net::LOAD_BYPASS_CACHE);
else if (existing_response_headers_.get())
AddConditionalHeaders(existing_response_headers_.get());
request_->Start();
}
void AppCacheUpdateJob::URLFetcher::OnReceivedRedirect(
const net::RedirectInfo& redirect_info) {
DCHECK(request_);
// Redirect is not allowed by the update process.
job_->MadeProgress();
redirect_response_code_ = request_->GetResponseCode();
request_->Cancel();
result_ = AppCacheUpdateJob::REDIRECT_ERROR;
OnResponseCompleted(net::ERR_ABORTED);
}
void AppCacheUpdateJob::URLFetcher::OnResponseStarted(int net_error) {
DCHECK(request_);
DCHECK_NE(net::ERR_IO_PENDING, net_error);
int response_code = -1;
if (net_error == net::OK) {
response_code = request_->GetResponseCode();
job_->MadeProgress();
}
if ((response_code / 100) != 2) {
if (response_code > 0)
result_ = AppCacheUpdateJob::SERVER_ERROR;
else
result_ = AppCacheUpdateJob::NETWORK_ERROR;
OnResponseCompleted(net_error);
return;
}
if (url_.SchemeIsCryptographic()) {
// Do not cache content with cert errors.
// Also, we willfully violate the HTML5 spec at this point in order
// to support the appcaching of cross-origin HTTPS resources.
// We've opted for a milder constraint and allow caching unless
// the resource has a "no-store" header. A spec change has been
// requested on the whatwg list.
// See http://code.google.com/p/chromium/issues/detail?id=69594
// TODO(michaeln): Consider doing this for cross-origin HTTP too.
if ((net::IsCertStatusError(
request_->GetResponseInfo().ssl_info.cert_status) &&
!base::CommandLine::ForCurrentProcess()->HasSwitch(
switches::kIgnoreCertificateErrors)) ||
(url_.GetOrigin() != job_->manifest_url_.GetOrigin() &&
request_->GetResponseHeaders()->HasHeaderValue("cache-control",
"no-store"))) {
DCHECK_EQ(-1, redirect_response_code_);
request_->Cancel();
result_ = AppCacheUpdateJob::SECURITY_ERROR;
OnResponseCompleted(net::ERR_ABORTED);
return;
}
}
// Write response info to storage for URL fetches. Wait for async write
// completion before reading any response data.
if (fetch_type_ == URL_FETCH || fetch_type_ == MASTER_ENTRY_FETCH) {
response_writer_ = job_->CreateResponseWriter();
scoped_refptr<HttpResponseInfoIOBuffer> io_buffer =
base::MakeRefCounted<HttpResponseInfoIOBuffer>(
std::make_unique<net::HttpResponseInfo>(
request_->GetResponseInfo()));
response_writer_->WriteInfo(
io_buffer.get(),
base::BindOnce(&URLFetcher::OnWriteComplete, base::Unretained(this)));
} else {
ReadResponseData();
}
}
void AppCacheUpdateJob::URLFetcher::OnReadCompleted(net::IOBuffer* buffer,
int bytes_read) {
DCHECK(request_);
DCHECK_NE(net::ERR_IO_PENDING, bytes_read);
if (bytes_read <= 0) {
OnResponseCompleted(bytes_read);
return;
}
job_->MadeProgress();
if (ConsumeResponseData(buffer, bytes_read))
request_->Read();
}
void AppCacheUpdateJob::URLFetcher::AddConditionalHeaders(
const net::HttpResponseHeaders* headers) {
DCHECK(request_);
DCHECK(headers);
net::HttpRequestHeaders extra_headers;
// Add If-Modified-Since header if response info has Last-Modified header.
const std::string last_modified = "Last-Modified";
std::string last_modified_value;
headers->EnumerateHeader(nullptr, last_modified, &last_modified_value);
if (!last_modified_value.empty()) {
extra_headers.SetHeader(net::HttpRequestHeaders::kIfModifiedSince,
last_modified_value);
}
// Add If-None-Match header if response info has ETag header.
const std::string etag = "ETag";
std::string etag_value;
headers->EnumerateHeader(nullptr, etag, &etag_value);
if (!etag_value.empty()) {
extra_headers.SetHeader(net::HttpRequestHeaders::kIfNoneMatch, etag_value);
}
if (!extra_headers.IsEmpty())
request_->SetExtraRequestHeaders(extra_headers);
}
void AppCacheUpdateJob::URLFetcher::OnWriteComplete(int result) {
if (result < 0) {
request_->Cancel();
result_ = AppCacheUpdateJob::DISKCACHE_ERROR;
OnResponseCompleted(net::ERR_ABORTED);
return;
}
ReadResponseData();
}
void AppCacheUpdateJob::URLFetcher::ReadResponseData() {
AppCacheUpdateJob::InternalUpdateState state = job_->internal_state_;
if (state == AppCacheUpdateJob::CACHE_FAILURE ||
state == AppCacheUpdateJob::CANCELLED ||
state == AppCacheUpdateJob::COMPLETED) {
return;
}
request_->Read();
}
// Returns false if response data is processed asynchronously, in which
// case ReadResponseData will be invoked when it is safe to continue
// reading more response data from the request.
bool AppCacheUpdateJob::URLFetcher::ConsumeResponseData(net::IOBuffer* buffer,
int bytes_read) {
DCHECK_GT(bytes_read, 0);
switch (fetch_type_) {
case MANIFEST_FETCH:
case MANIFEST_REFETCH:
manifest_data_.append(buffer->data(), bytes_read);
break;
case URL_FETCH:
case MASTER_ENTRY_FETCH:
DCHECK(response_writer_.get());
response_writer_->WriteData(
buffer, bytes_read,
base::BindOnce(&URLFetcher::OnWriteComplete, base::Unretained(this)));
return false; // wait for async write completion to continue reading
default:
NOTREACHED();
}
return true;
}
void AppCacheUpdateJob::URLFetcher::OnResponseCompleted(int net_error) {
if (net_error == net::OK) {
job_->MadeProgress();
} else if (result_ == AppCacheUpdateJob::UPDATE_OK) {
result_ = AppCacheUpdateJob::NETWORK_ERROR;
}
// Retry for 503s where retry-after is 0.
if (net_error == net::OK && request_->GetResponseCode() == 503 &&
MaybeRetryRequest()) {
return;
}
switch (fetch_type_) {
case MANIFEST_FETCH:
job_->HandleManifestFetchCompleted(this, net_error);
break;
case URL_FETCH:
job_->HandleUrlFetchCompleted(this, net_error);
break;
case MASTER_ENTRY_FETCH:
job_->HandleMasterEntryFetchCompleted(this, net_error);
break;
case MANIFEST_REFETCH:
job_->HandleManifestRefetchCompleted(this, net_error);
break;
default:
NOTREACHED();
}
delete this;
}
bool AppCacheUpdateJob::URLFetcher::MaybeRetryRequest() {
if (retry_503_attempts_ >= kMax503Retries ||
!request_->GetResponseHeaders()->HasHeaderValue("retry-after", "0")) {
return false;
}
++retry_503_attempts_;
result_ = AppCacheUpdateJob::UPDATE_OK;
request_ =
UpdateRequestBase::Create(job_->service_, url_, buffer_size_, this);
Start();
return true;
}
} // namespace content.
|
