OLD | NEW |
| (Empty) |
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 // This file declares HttpCache::Transaction, a private class of HttpCache so | |
6 // it should only be included by http_cache.cc | |
7 | |
8 #ifndef NET_HTTP_HTTP_CACHE_TRANSACTION_H_ | |
9 #define NET_HTTP_HTTP_CACHE_TRANSACTION_H_ | |
10 | |
11 #include <string> | |
12 | |
13 #include "base/time/time.h" | |
14 #include "net/base/completion_callback.h" | |
15 #include "net/base/net_log.h" | |
16 #include "net/base/request_priority.h" | |
17 #include "net/http/http_cache.h" | |
18 #include "net/http/http_request_headers.h" | |
19 #include "net/http/http_response_headers.h" | |
20 #include "net/http/http_response_info.h" | |
21 #include "net/http/http_transaction.h" | |
22 | |
23 namespace net { | |
24 | |
25 class PartialData; | |
26 struct HttpRequestInfo; | |
27 struct LoadTimingInfo; | |
28 | |
29 // This is the transaction that is returned by the HttpCache transaction | |
30 // factory. | |
31 class HttpCache::Transaction : public HttpTransaction { | |
32 public: | |
33 // The transaction has the following modes, which apply to how it may access | |
34 // its cache entry. | |
35 // | |
36 // o If the mode of the transaction is NONE, then it is in "pass through" | |
37 // mode and all methods just forward to the inner network transaction. | |
38 // | |
39 // o If the mode of the transaction is only READ, then it may only read from | |
40 // the cache entry. | |
41 // | |
42 // o If the mode of the transaction is only WRITE, then it may only write to | |
43 // the cache entry. | |
44 // | |
45 // o If the mode of the transaction is READ_WRITE, then the transaction may | |
46 // optionally modify the cache entry (e.g., possibly corresponding to | |
47 // cache validation). | |
48 // | |
49 // o If the mode of the transaction is UPDATE, then the transaction may | |
50 // update existing cache entries, but will never create a new entry or | |
51 // respond using the entry read from the cache. | |
52 enum Mode { | |
53 NONE = 0, | |
54 READ_META = 1 << 0, | |
55 READ_DATA = 1 << 1, | |
56 READ = READ_META | READ_DATA, | |
57 WRITE = 1 << 2, | |
58 READ_WRITE = READ | WRITE, | |
59 UPDATE = READ_META | WRITE, // READ_WRITE & ~READ_DATA | |
60 }; | |
61 | |
62 Transaction(RequestPriority priority, | |
63 HttpCache* cache); | |
64 ~Transaction() override; | |
65 | |
66 Mode mode() const { return mode_; } | |
67 | |
68 const std::string& key() const { return cache_key_; } | |
69 | |
70 // Writes |buf_len| bytes of meta-data from the provided buffer |buf|. to the | |
71 // HTTP cache entry that backs this transaction (if any). | |
72 // Returns the number of bytes actually written, or a net error code. If the | |
73 // operation cannot complete immediately, returns ERR_IO_PENDING, grabs a | |
74 // reference to the buffer (until completion), and notifies the caller using | |
75 // the provided |callback| when the operation finishes. | |
76 // | |
77 // The first time this method is called for a given transaction, previous | |
78 // meta-data will be overwritten with the provided data, and subsequent | |
79 // invocations will keep appending to the cached entry. | |
80 // | |
81 // In order to guarantee that the metadata is set to the correct entry, the | |
82 // response (or response info) must be evaluated by the caller, for instance | |
83 // to make sure that the response_time is as expected, before calling this | |
84 // method. | |
85 int WriteMetadata(IOBuffer* buf, | |
86 int buf_len, | |
87 const CompletionCallback& callback); | |
88 | |
89 // This transaction is being deleted and we are not done writing to the cache. | |
90 // We need to indicate that the response data was truncated. Returns true on | |
91 // success. Keep in mind that this operation may have side effects, such as | |
92 // deleting the active entry. | |
93 bool AddTruncatedFlag(); | |
94 | |
95 HttpCache::ActiveEntry* entry() { return entry_; } | |
96 | |
97 // Returns the LoadState of the writer transaction of a given ActiveEntry. In | |
98 // other words, returns the LoadState of this transaction without asking the | |
99 // http cache, because this transaction should be the one currently writing | |
100 // to the cache entry. | |
101 LoadState GetWriterLoadState() const; | |
102 | |
103 const CompletionCallback& io_callback() { return io_callback_; } | |
104 | |
105 const BoundNetLog& net_log() const; | |
106 | |
107 // Bypasses the cache lock whenever there is lock contention. | |
108 void BypassLockForTest() { | |
109 bypass_lock_for_test_ = true; | |
110 } | |
111 | |
112 // Generates a failure when attempting to conditionalize a network request. | |
113 void FailConditionalizationForTest() { | |
114 fail_conditionalization_for_test_ = true; | |
115 } | |
116 | |
117 // HttpTransaction methods: | |
118 int Start(const HttpRequestInfo* request_info, | |
119 const CompletionCallback& callback, | |
120 const BoundNetLog& net_log) override; | |
121 int RestartIgnoringLastError(const CompletionCallback& callback) override; | |
122 int RestartWithCertificate(X509Certificate* client_cert, | |
123 const CompletionCallback& callback) override; | |
124 int RestartWithAuth(const AuthCredentials& credentials, | |
125 const CompletionCallback& callback) override; | |
126 bool IsReadyToRestartForAuth() override; | |
127 int Read(IOBuffer* buf, | |
128 int buf_len, | |
129 const CompletionCallback& callback) override; | |
130 void StopCaching() override; | |
131 bool GetFullRequestHeaders(HttpRequestHeaders* headers) const override; | |
132 int64 GetTotalReceivedBytes() const override; | |
133 void DoneReading() override; | |
134 const HttpResponseInfo* GetResponseInfo() const override; | |
135 LoadState GetLoadState() const override; | |
136 UploadProgress GetUploadProgress(void) const override; | |
137 void SetQuicServerInfo(QuicServerInfo* quic_server_info) override; | |
138 bool GetLoadTimingInfo(LoadTimingInfo* load_timing_info) const override; | |
139 void SetPriority(RequestPriority priority) override; | |
140 void SetWebSocketHandshakeStreamCreateHelper( | |
141 net::WebSocketHandshakeStreamBase::CreateHelper* create_helper) override; | |
142 void SetBeforeNetworkStartCallback( | |
143 const BeforeNetworkStartCallback& callback) override; | |
144 void SetBeforeProxyHeadersSentCallback( | |
145 const BeforeProxyHeadersSentCallback& callback) override; | |
146 int ResumeNetworkStart() override; | |
147 | |
148 private: | |
149 static const size_t kNumValidationHeaders = 2; | |
150 // Helper struct to pair a header name with its value, for | |
151 // headers used to validate cache entries. | |
152 struct ValidationHeaders { | |
153 ValidationHeaders() : initialized(false) {} | |
154 | |
155 std::string values[kNumValidationHeaders]; | |
156 bool initialized; | |
157 }; | |
158 | |
159 enum State { | |
160 STATE_NONE, | |
161 STATE_GET_BACKEND, | |
162 STATE_GET_BACKEND_COMPLETE, | |
163 STATE_SEND_REQUEST, | |
164 STATE_SEND_REQUEST_COMPLETE, | |
165 STATE_SUCCESSFUL_SEND_REQUEST, | |
166 STATE_NETWORK_READ, | |
167 STATE_NETWORK_READ_COMPLETE, | |
168 STATE_INIT_ENTRY, | |
169 STATE_OPEN_ENTRY, | |
170 STATE_OPEN_ENTRY_COMPLETE, | |
171 STATE_CREATE_ENTRY, | |
172 STATE_CREATE_ENTRY_COMPLETE, | |
173 STATE_DOOM_ENTRY, | |
174 STATE_DOOM_ENTRY_COMPLETE, | |
175 STATE_ADD_TO_ENTRY, | |
176 STATE_ADD_TO_ENTRY_COMPLETE, | |
177 STATE_START_PARTIAL_CACHE_VALIDATION, | |
178 STATE_COMPLETE_PARTIAL_CACHE_VALIDATION, | |
179 STATE_UPDATE_CACHED_RESPONSE, | |
180 STATE_UPDATE_CACHED_RESPONSE_COMPLETE, | |
181 STATE_OVERWRITE_CACHED_RESPONSE, | |
182 STATE_TRUNCATE_CACHED_DATA, | |
183 STATE_TRUNCATE_CACHED_DATA_COMPLETE, | |
184 STATE_TRUNCATE_CACHED_METADATA, | |
185 STATE_TRUNCATE_CACHED_METADATA_COMPLETE, | |
186 STATE_PARTIAL_HEADERS_RECEIVED, | |
187 STATE_CACHE_READ_RESPONSE, | |
188 STATE_CACHE_READ_RESPONSE_COMPLETE, | |
189 STATE_CACHE_DISPATCH_VALIDATION, | |
190 STATE_TOGGLE_UNUSED_SINCE_PREFETCH, | |
191 STATE_TOGGLE_UNUSED_SINCE_PREFETCH_COMPLETE, | |
192 STATE_CACHE_WRITE_RESPONSE, | |
193 STATE_CACHE_WRITE_TRUNCATED_RESPONSE, | |
194 STATE_CACHE_WRITE_RESPONSE_COMPLETE, | |
195 STATE_CACHE_READ_METADATA, | |
196 STATE_CACHE_READ_METADATA_COMPLETE, | |
197 STATE_CACHE_QUERY_DATA, | |
198 STATE_CACHE_QUERY_DATA_COMPLETE, | |
199 STATE_CACHE_READ_DATA, | |
200 STATE_CACHE_READ_DATA_COMPLETE, | |
201 STATE_CACHE_WRITE_DATA, | |
202 STATE_CACHE_WRITE_DATA_COMPLETE | |
203 }; | |
204 | |
205 // Used for categorizing transactions for reporting in histograms. Patterns | |
206 // cover relatively common use cases being measured and considered for | |
207 // optimization. Many use cases that are more complex or uncommon are binned | |
208 // as PATTERN_NOT_COVERED, and details are not reported. | |
209 // NOTE: This enumeration is used in histograms, so please do not add entries | |
210 // in the middle. | |
211 enum TransactionPattern { | |
212 PATTERN_UNDEFINED, | |
213 PATTERN_NOT_COVERED, | |
214 PATTERN_ENTRY_NOT_CACHED, | |
215 PATTERN_ENTRY_USED, | |
216 PATTERN_ENTRY_VALIDATED, | |
217 PATTERN_ENTRY_UPDATED, | |
218 PATTERN_ENTRY_CANT_CONDITIONALIZE, | |
219 PATTERN_MAX, | |
220 }; | |
221 | |
222 // This is a helper function used to trigger a completion callback. It may | |
223 // only be called if callback_ is non-null. | |
224 void DoCallback(int rv); | |
225 | |
226 // This will trigger the completion callback if appropriate. | |
227 int HandleResult(int rv); | |
228 | |
229 // Runs the state transition loop. | |
230 int DoLoop(int result); | |
231 | |
232 // Each of these methods corresponds to a State value. If there is an | |
233 // argument, the value corresponds to the return of the previous state or | |
234 // corresponding callback. | |
235 int DoGetBackend(); | |
236 int DoGetBackendComplete(int result); | |
237 int DoSendRequest(); | |
238 int DoSendRequestComplete(int result); | |
239 int DoSuccessfulSendRequest(); | |
240 int DoNetworkRead(); | |
241 int DoNetworkReadComplete(int result); | |
242 int DoInitEntry(); | |
243 int DoOpenEntry(); | |
244 int DoOpenEntryComplete(int result); | |
245 int DoCreateEntry(); | |
246 int DoCreateEntryComplete(int result); | |
247 int DoDoomEntry(); | |
248 int DoDoomEntryComplete(int result); | |
249 int DoAddToEntry(); | |
250 int DoAddToEntryComplete(int result); | |
251 int DoStartPartialCacheValidation(); | |
252 int DoCompletePartialCacheValidation(int result); | |
253 int DoUpdateCachedResponse(); | |
254 int DoUpdateCachedResponseComplete(int result); | |
255 int DoOverwriteCachedResponse(); | |
256 int DoTruncateCachedData(); | |
257 int DoTruncateCachedDataComplete(int result); | |
258 int DoTruncateCachedMetadata(); | |
259 int DoTruncateCachedMetadataComplete(int result); | |
260 int DoPartialHeadersReceived(); | |
261 int DoCacheReadResponse(); | |
262 int DoCacheReadResponseComplete(int result); | |
263 int DoCacheDispatchValidation(); | |
264 int DoCacheToggleUnusedSincePrefetch(); | |
265 int DoCacheToggleUnusedSincePrefetchComplete(int result); | |
266 int DoCacheWriteResponse(); | |
267 int DoCacheWriteTruncatedResponse(); | |
268 int DoCacheWriteResponseComplete(int result); | |
269 int DoCacheReadMetadata(); | |
270 int DoCacheReadMetadataComplete(int result); | |
271 int DoCacheQueryData(); | |
272 int DoCacheQueryDataComplete(int result); | |
273 int DoCacheReadData(); | |
274 int DoCacheReadDataComplete(int result); | |
275 int DoCacheWriteData(int num_bytes); | |
276 int DoCacheWriteDataComplete(int result); | |
277 | |
278 // These functions are involved in a field trial testing storing certificates | |
279 // in seperate entries from the HttpResponseInfo. | |
280 void ReadCertChain(); | |
281 void WriteCertChain(); | |
282 | |
283 // Sets request_ and fields derived from it. | |
284 void SetRequest(const BoundNetLog& net_log, const HttpRequestInfo* request); | |
285 | |
286 // Returns true if the request should be handled exclusively by the network | |
287 // layer (skipping the cache entirely). | |
288 bool ShouldPassThrough(); | |
289 | |
290 // Called to begin reading from the cache. Returns network error code. | |
291 int BeginCacheRead(); | |
292 | |
293 // Called to begin validating the cache entry. Returns network error code. | |
294 int BeginCacheValidation(); | |
295 | |
296 // Called to begin validating an entry that stores partial content. Returns | |
297 // a network error code. | |
298 int BeginPartialCacheValidation(); | |
299 | |
300 // Validates the entry headers against the requested range and continues with | |
301 // the validation of the rest of the entry. Returns a network error code. | |
302 int ValidateEntryHeadersAndContinue(); | |
303 | |
304 // Called to start requests which were given an "if-modified-since" or | |
305 // "if-none-match" validation header by the caller (NOT when the request was | |
306 // conditionalized internally in response to LOAD_VALIDATE_CACHE). | |
307 // Returns a network error code. | |
308 int BeginExternallyConditionalizedRequest(); | |
309 | |
310 // Called to restart a network transaction after an error. Returns network | |
311 // error code. | |
312 int RestartNetworkRequest(); | |
313 | |
314 // Called to restart a network transaction with a client certificate. | |
315 // Returns network error code. | |
316 int RestartNetworkRequestWithCertificate(X509Certificate* client_cert); | |
317 | |
318 // Called to restart a network transaction with authentication credentials. | |
319 // Returns network error code. | |
320 int RestartNetworkRequestWithAuth(const AuthCredentials& credentials); | |
321 | |
322 // Called to determine if we need to validate the cache entry before using it, | |
323 // and whether the validation should be synchronous or asynchronous. | |
324 ValidationType RequiresValidation(); | |
325 | |
326 // Called to make the request conditional (to ask the server if the cached | |
327 // copy is valid). Returns true if able to make the request conditional. | |
328 bool ConditionalizeRequest(); | |
329 | |
330 // Makes sure that a 206 response is expected. Returns true on success. | |
331 // On success, handling_206_ will be set to true if we are processing a | |
332 // partial entry. | |
333 bool ValidatePartialResponse(); | |
334 | |
335 // Handles a response validation error by bypassing the cache. | |
336 void IgnoreRangeRequest(); | |
337 | |
338 // Fixes the response headers to match expectations for a HEAD request. | |
339 void FixHeadersForHead(); | |
340 | |
341 // Launches an asynchronous revalidation based on this transaction. | |
342 void TriggerAsyncValidation(); | |
343 | |
344 // Changes the response code of a range request to be 416 (Requested range not | |
345 // satisfiable). | |
346 void FailRangeRequest(); | |
347 | |
348 // Setups the transaction for reading from the cache entry. | |
349 int SetupEntryForRead(); | |
350 | |
351 // Reads data from the network. | |
352 int ReadFromNetwork(IOBuffer* data, int data_len); | |
353 | |
354 // Reads data from the cache entry. | |
355 int ReadFromEntry(IOBuffer* data, int data_len); | |
356 | |
357 // Called to write data to the cache entry. If the write fails, then the | |
358 // cache entry is destroyed. Future calls to this function will just do | |
359 // nothing without side-effect. Returns a network error code. | |
360 int WriteToEntry(int index, int offset, IOBuffer* data, int data_len, | |
361 const CompletionCallback& callback); | |
362 | |
363 // Called to write response_ to the cache entry. |truncated| indicates if the | |
364 // entry should be marked as incomplete. | |
365 int WriteResponseInfoToEntry(bool truncated); | |
366 | |
367 // Called to append response data to the cache entry. Returns a network error | |
368 // code. | |
369 int AppendResponseDataToEntry(IOBuffer* data, int data_len, | |
370 const CompletionCallback& callback); | |
371 | |
372 // Called when we are done writing to the cache entry. | |
373 void DoneWritingToEntry(bool success); | |
374 | |
375 // Returns an error to signal the caller that the current read failed. The | |
376 // current operation |result| is also logged. If |restart| is true, the | |
377 // transaction should be restarted. | |
378 int OnCacheReadError(int result, bool restart); | |
379 | |
380 // Called when the cache lock timeout fires. | |
381 void OnAddToEntryTimeout(base::TimeTicks start_time); | |
382 | |
383 // Deletes the current partial cache entry (sparse), and optionally removes | |
384 // the control object (partial_). | |
385 void DoomPartialEntry(bool delete_object); | |
386 | |
387 // Performs the needed work after receiving data from the network, when | |
388 // working with range requests. | |
389 int DoPartialNetworkReadCompleted(int result); | |
390 | |
391 // Performs the needed work after receiving data from the cache, when | |
392 // working with range requests. | |
393 int DoPartialCacheReadCompleted(int result); | |
394 | |
395 // Restarts this transaction after deleting the cached data. It is meant to | |
396 // be used when the current request cannot be fulfilled due to conflicts | |
397 // between the byte range request and the cached entry. | |
398 int DoRestartPartialRequest(); | |
399 | |
400 // Resets the relavant internal state to remove traces of internal processing | |
401 // related to range requests. Deletes |partial_| if |delete_object| is true. | |
402 void ResetPartialState(bool delete_object); | |
403 | |
404 // Resets |network_trans_|, which must be non-NULL. Also updates | |
405 // |old_network_trans_load_timing_|, which must be NULL when this is called. | |
406 void ResetNetworkTransaction(); | |
407 | |
408 // Returns true if we should bother attempting to resume this request if it | |
409 // is aborted while in progress. If |has_data| is true, the size of the stored | |
410 // data is considered for the result. | |
411 bool CanResume(bool has_data); | |
412 | |
413 void UpdateTransactionPattern(TransactionPattern new_transaction_pattern); | |
414 void RecordHistograms(); | |
415 | |
416 // Called to signal completion of asynchronous IO. | |
417 void OnIOComplete(int result); | |
418 | |
419 State next_state_; | |
420 const HttpRequestInfo* request_; | |
421 RequestPriority priority_; | |
422 BoundNetLog net_log_; | |
423 scoped_ptr<HttpRequestInfo> custom_request_; | |
424 HttpRequestHeaders request_headers_copy_; | |
425 // If extra_headers specified a "if-modified-since" or "if-none-match", | |
426 // |external_validation_| contains the value of those headers. | |
427 ValidationHeaders external_validation_; | |
428 base::WeakPtr<HttpCache> cache_; | |
429 HttpCache::ActiveEntry* entry_; | |
430 HttpCache::ActiveEntry* new_entry_; | |
431 scoped_ptr<HttpTransaction> network_trans_; | |
432 CompletionCallback callback_; // Consumer's callback. | |
433 HttpResponseInfo response_; | |
434 HttpResponseInfo auth_response_; | |
435 const HttpResponseInfo* new_response_; | |
436 std::string cache_key_; | |
437 Mode mode_; | |
438 State target_state_; | |
439 bool reading_; // We are already reading. Never reverts to false once set. | |
440 bool invalid_range_; // We may bypass the cache for this request. | |
441 bool truncated_; // We don't have all the response data. | |
442 bool is_sparse_; // The data is stored in sparse byte ranges. | |
443 bool range_requested_; // The user requested a byte range. | |
444 bool handling_206_; // We must deal with this 206 response. | |
445 bool cache_pending_; // We are waiting for the HttpCache. | |
446 bool done_reading_; // All available data was read. | |
447 bool vary_mismatch_; // The request doesn't match the stored vary data. | |
448 bool couldnt_conditionalize_request_; | |
449 bool bypass_lock_for_test_; // A test is exercising the cache lock. | |
450 bool fail_conditionalization_for_test_; // Fail ConditionalizeRequest. | |
451 scoped_refptr<IOBuffer> read_buf_; | |
452 int io_buf_len_; | |
453 int read_offset_; | |
454 int effective_load_flags_; | |
455 int write_len_; | |
456 scoped_ptr<PartialData> partial_; // We are dealing with range requests. | |
457 UploadProgress final_upload_progress_; | |
458 CompletionCallback io_callback_; | |
459 | |
460 // Members used to track data for histograms. | |
461 TransactionPattern transaction_pattern_; | |
462 base::TimeTicks entry_lock_waiting_since_; | |
463 base::TimeTicks first_cache_access_since_; | |
464 base::TimeTicks send_request_since_; | |
465 | |
466 int64 total_received_bytes_; | |
467 | |
468 // Load timing information for the last network request, if any. Set in the | |
469 // 304 and 206 response cases, as the network transaction may be destroyed | |
470 // before the caller requests load timing information. | |
471 scoped_ptr<LoadTimingInfo> old_network_trans_load_timing_; | |
472 | |
473 // The helper object to use to create WebSocketHandshakeStreamBase | |
474 // objects. Only relevant when establishing a WebSocket connection. | |
475 // This is passed to the underlying network transaction. It is stored here in | |
476 // case the transaction does not exist yet. | |
477 WebSocketHandshakeStreamBase::CreateHelper* | |
478 websocket_handshake_stream_base_create_helper_; | |
479 | |
480 BeforeNetworkStartCallback before_network_start_callback_; | |
481 BeforeProxyHeadersSentCallback before_proxy_headers_sent_callback_; | |
482 | |
483 base::WeakPtrFactory<Transaction> weak_factory_; | |
484 | |
485 DISALLOW_COPY_AND_ASSIGN(Transaction); | |
486 }; | |
487 | |
488 } // namespace net | |
489 | |
490 #endif // NET_HTTP_HTTP_CACHE_TRANSACTION_H_ | |
OLD | NEW |