MediaWiki REL1_32
fixT22757.php
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1<?php
24require_once __DIR__ . '/../Maintenance.php';
25
31class FixT22757 extends Maintenance {
32 public $batchSize = 10000;
33 public $mapCache = [];
34 public $mapCacheSize = 0;
35 public $maxMapCacheSize = 1000000;
36
37 function __construct() {
38 parent::__construct();
39 $this->addDescription( 'Script to fix T22757 assuming that blob_tracking is intact' );
40 $this->addOption( 'dry-run', 'Report only' );
41 $this->addOption( 'start', 'old_id to start at', false, true );
42 }
43
44 function execute() {
45 $dbr = $this->getDB( DB_REPLICA );
46 $dbw = $this->getDB( DB_MASTER );
47
48 $dryRun = $this->getOption( 'dry-run' );
49 if ( $dryRun ) {
50 print "Dry run only.\n";
51 }
52
53 $startId = $this->getOption( 'start', 0 );
54 $numGood = 0;
55 $numFixed = 0;
56 $numBad = 0;
57
58 $totalRevs = $dbr->selectField( 'text', 'MAX(old_id)', '', __METHOD__ );
59
60 // In MySQL 4.1+, the binary field old_text has a non-working LOWER() function
61 $lowerLeft = 'LOWER(CONVERT(LEFT(old_text,22) USING latin1))';
62
63 while ( true ) {
64 print "ID: $startId / $totalRevs\r";
65
66 $res = $dbr->select(
67 'text',
68 [ 'old_id', 'old_flags', 'old_text' ],
69 [
70 'old_id > ' . intval( $startId ),
71 'old_flags LIKE \'%object%\' AND old_flags NOT LIKE \'%external%\'',
72 "$lowerLeft = 'o:15:\"historyblobstub\"'",
73 ],
74 __METHOD__,
75 [
76 'ORDER BY' => 'old_id',
77 'LIMIT' => $this->batchSize,
78 ]
79 );
80
81 if ( !$res->numRows() ) {
82 break;
83 }
84
85 $secondaryIds = [];
86 $stubs = [];
87
88 foreach ( $res as $row ) {
89 $startId = $row->old_id;
90
91 // Basic sanity checks
92 $obj = unserialize( $row->old_text );
93 if ( $obj === false ) {
94 print "{$row->old_id}: unrecoverable: cannot unserialize\n";
95 ++$numBad;
96 continue;
97 }
98
99 if ( !is_object( $obj ) ) {
100 print "{$row->old_id}: unrecoverable: unserialized to type " .
101 gettype( $obj ) . ", possible double-serialization\n";
102 ++$numBad;
103 continue;
104 }
105
106 if ( strtolower( get_class( $obj ) ) !== 'historyblobstub' ) {
107 print "{$row->old_id}: unrecoverable: unexpected object class " .
108 get_class( $obj ) . "\n";
109 ++$numBad;
110 continue;
111 }
112
113 // Process flags
114 $flags = explode( ',', $row->old_flags );
115 if ( in_array( 'utf-8', $flags ) || in_array( 'utf8', $flags ) ) {
116 $legacyEncoding = false;
117 } else {
118 $legacyEncoding = true;
119 }
120
121 // Queue the stub for future batch processing
122 $id = intval( $obj->mOldId );
123 $secondaryIds[] = $id;
124 $stubs[$row->old_id] = [
125 'legacyEncoding' => $legacyEncoding,
126 'secondaryId' => $id,
127 'hash' => $obj->mHash,
128 ];
129 }
130
131 $secondaryIds = array_unique( $secondaryIds );
132
133 if ( !count( $secondaryIds ) ) {
134 continue;
135 }
136
137 // Run the batch query on blob_tracking
138 $res = $dbr->select(
139 'blob_tracking',
140 '*',
141 [
142 'bt_text_id' => $secondaryIds,
143 ],
144 __METHOD__
145 );
146 $trackedBlobs = [];
147 foreach ( $res as $row ) {
148 $trackedBlobs[$row->bt_text_id] = $row;
149 }
150
151 // Process the stubs
152 foreach ( $stubs as $primaryId => $stub ) {
153 $secondaryId = $stub['secondaryId'];
154 if ( !isset( $trackedBlobs[$secondaryId] ) ) {
155 // No tracked blob. Work out what went wrong
156 $secondaryRow = $dbr->selectRow(
157 'text',
158 [ 'old_flags', 'old_text' ],
159 [ 'old_id' => $secondaryId ],
160 __METHOD__
161 );
162 if ( !$secondaryRow ) {
163 print "$primaryId: unrecoverable: secondary row is missing\n";
164 ++$numBad;
165 } elseif ( $this->isUnbrokenStub( $stub, $secondaryRow ) ) {
166 // Not broken yet, and not in the tracked clusters so it won't get
167 // broken by the current RCT run.
168 ++$numGood;
169 } elseif ( strpos( $secondaryRow->old_flags, 'external' ) !== false ) {
170 print "$primaryId: unrecoverable: secondary gone to {$secondaryRow->old_text}\n";
171 ++$numBad;
172 } else {
173 print "$primaryId: unrecoverable: miscellaneous corruption of secondary row\n";
174 ++$numBad;
175 }
176 unset( $stubs[$primaryId] );
177 continue;
178 }
179 $trackRow = $trackedBlobs[$secondaryId];
180
181 // Check that the specified text really is available in the tracked source row
182 $url = "DB://{$trackRow->bt_cluster}/{$trackRow->bt_blob_id}/{$stub['hash']}";
183 $text = ExternalStore::fetchFromURL( $url );
184 if ( $text === false ) {
185 print "$primaryId: unrecoverable: source text missing\n";
186 ++$numBad;
187 unset( $stubs[$primaryId] );
188 continue;
189 }
190 if ( md5( $text ) !== $stub['hash'] ) {
191 print "$primaryId: unrecoverable: content hashes do not match\n";
192 ++$numBad;
193 unset( $stubs[$primaryId] );
194 continue;
195 }
196
197 // Find the page_id and rev_id
198 // The page is probably the same as the page of the secondary row
199 $pageId = intval( $trackRow->bt_page );
200 if ( !$pageId ) {
201 $revId = $pageId = 0;
202 } else {
203 $revId = $this->findTextIdInPage( $pageId, $primaryId );
204 if ( !$revId ) {
205 // Actually an orphan
206 $pageId = $revId = 0;
207 }
208 }
209
210 $newFlags = $stub['legacyEncoding'] ? 'external' : 'external,utf-8';
211
212 if ( !$dryRun ) {
213 // Reset the text row to point to the original copy
214 $this->beginTransaction( $dbw, __METHOD__ );
215 $dbw->update(
216 'text',
217 // SET
218 [
219 'old_flags' => $newFlags,
220 'old_text' => $url
221 ],
222 // WHERE
223 [ 'old_id' => $primaryId ],
224 __METHOD__
225 );
226
227 // Add a blob_tracking row so that the new reference can be recompressed
228 // without needing to run trackBlobs.php again
229 $dbw->insert( 'blob_tracking',
230 [
231 'bt_page' => $pageId,
232 'bt_rev_id' => $revId,
233 'bt_text_id' => $primaryId,
234 'bt_cluster' => $trackRow->bt_cluster,
235 'bt_blob_id' => $trackRow->bt_blob_id,
236 'bt_cgz_hash' => $stub['hash'],
237 'bt_new_url' => null,
238 'bt_moved' => 0,
239 ],
240 __METHOD__
241 );
242 $this->commitTransaction( $dbw, __METHOD__ );
243 }
244
245 print "$primaryId: resolved to $url\n";
246 ++$numFixed;
247 }
248 }
249
250 print "\n";
251 print "Fixed: $numFixed\n";
252 print "Unrecoverable: $numBad\n";
253 print "Good stubs: $numGood\n";
254 }
255
256 function findTextIdInPage( $pageId, $textId ) {
257 $ids = $this->getRevTextMap( $pageId );
258 if ( !isset( $ids[$textId] ) ) {
259 return null;
260 } else {
261 return $ids[$textId];
262 }
263 }
264
265 function getRevTextMap( $pageId ) {
266 if ( !isset( $this->mapCache[$pageId] ) ) {
267 // Limit cache size
268 while ( $this->mapCacheSize > $this->maxMapCacheSize ) {
269 $key = key( $this->mapCache );
270 $this->mapCacheSize -= count( $this->mapCache[$key] );
271 unset( $this->mapCache[$key] );
272 }
273
274 $dbr = $this->getDB( DB_REPLICA );
275 $map = [];
276 $res = $dbr->select( 'revision',
277 [ 'rev_id', 'rev_text_id' ],
278 [ 'rev_page' => $pageId ],
279 __METHOD__
280 );
281 foreach ( $res as $row ) {
282 $map[$row->rev_text_id] = $row->rev_id;
283 }
284 $this->mapCache[$pageId] = $map;
285 $this->mapCacheSize += count( $map );
286 }
287
288 return $this->mapCache[$pageId];
289 }
290
298 function isUnbrokenStub( $stub, $secondaryRow ) {
299 $flags = explode( ',', $secondaryRow->old_flags );
300 $text = $secondaryRow->old_text;
301 if ( in_array( 'external', $flags ) ) {
302 $url = $text;
303 Wikimedia\suppressWarnings();
304 list( /* $proto */, $path ) = explode( '://', $url, 2 );
305 Wikimedia\restoreWarnings();
306
307 if ( $path == "" ) {
308 return false;
309 }
310 $text = ExternalStore::fetchFromURL( $url );
311 }
312 if ( !in_array( 'object', $flags ) ) {
313 return false;
314 }
315
316 if ( in_array( 'gzip', $flags ) ) {
317 $obj = unserialize( gzinflate( $text ) );
318 } else {
319 $obj = unserialize( $text );
320 }
321
322 if ( !is_object( $obj ) ) {
323 // Correct for old double-serialization bug.
324 $obj = unserialize( $obj );
325 }
326
327 if ( !is_object( $obj ) ) {
328 return false;
329 }
330
331 $obj->uncompress();
332 $text = $obj->getItem( $stub['hash'] );
333
334 return $text !== false;
335 }
336}
337
338$maintClass = FixT22757::class;
339require_once RUN_MAINTENANCE_IF_MAIN;
unserialize( $serialized)
Maintenance script to fix T22757.
Definition fixT22757.php:31
__construct()
Default constructor.
Definition fixT22757.php:37
getRevTextMap( $pageId)
isUnbrokenStub( $stub, $secondaryRow)
This is based on part of HistoryBlobStub::getText().
findTextIdInPage( $pageId, $textId)
execute()
Do the actual work.
Definition fixT22757.php:44
Abstract maintenance class for quickly writing and churning out maintenance scripts with minimal effo...
beginTransaction(IDatabase $dbw, $fname)
Begin a transcation on a DB.
commitTransaction(IDatabase $dbw, $fname)
Commit the transcation on a DB handle and wait for replica DBs to catch up.
getDB( $db, $groups=[], $wiki=false)
Returns a database to be used by current maintenance script.
addDescription( $text)
Set the description text.
addOption( $name, $description, $required=false, $withArg=false, $shortName=false, $multiOccurrence=false)
Add a parameter to the script.
getOption( $name, $default=null)
Get an option, or return the default.
$res
Definition database.txt:21
deferred txt A few of the database updates required by various functions here can be deferred until after the result page is displayed to the user For updating the view updating the linked to tables after a etc PHP does not yet have any way to tell the server to actually return and disconnect while still running these but it might have such a feature in the future We handle these by creating a deferred update object and putting those objects on a global list
Definition deferred.txt:11
This document is intended to provide useful advice for parties seeking to redistribute MediaWiki to end users It s targeted particularly at maintainers for Linux since it s been observed that distribution packages of MediaWiki often break We ve consistently had to recommend that users seeking support use official tarballs instead of their distribution s and this often solves whatever problem the user is having It would be nice if this could such as
while(( $__line=Maintenance::readconsole()) !==false) print
Definition eval.php:64
$maintClass
either a unescaped string or a HtmlArmor object after in associative array form externallinks including delete and has completed for all link tables whether this was an auto creation use $formDescriptor instead default is conds Array Extra conditions for the No matching items in log is displayed if loglist is empty msgKey Array If you want a nice box with a set this to the key of the message First element is the message key
Definition hooks.txt:2214
injection txt This is an overview of how MediaWiki makes use of dependency injection The design described here grew from the discussion of RFC T384 The term dependency this means that anything an object needs to operate should be injected from the the object itself should only know narrow no concrete implementation of the logic it relies on The requirement to inject everything typically results in an architecture that based on two main types of and essentially stateless service objects that use other service objects to operate on the value objects As of the beginning MediaWiki is only starting to use the DI approach Much of the code still relies on global state or direct resulting in a highly cyclical dependency which acts as the top level factory for services in MediaWiki which can be used to gain access to default instances of various services MediaWikiServices however also allows new services to be defined and default services to be redefined Services are defined or redefined by providing a callback the instantiator that will return a new instance of the service When it will create an instance of MediaWikiServices and populate it with the services defined in the files listed by thereby bootstrapping the DI framework Per $wgServiceWiringFiles lists includes ServiceWiring php
Definition injection.txt:37
require_once RUN_MAINTENANCE_IF_MAIN
const DB_REPLICA
Definition defines.php:25
const DB_MASTER
Definition defines.php:26