MediaWiki  master
migrateComments.php
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1 <?php
25 
26 require_once __DIR__ . '/Maintenance.php';
27 
35  public function __construct() {
36  parent::__construct();
37  $this->addDescription( 'Migrates comments from pre-1.30 columns to the \'comment\' table' );
38  $this->setBatchSize( 100 );
39  }
40 
41  protected function getUpdateKey() {
42  return __CLASS__;
43  }
44 
45  protected function updateSkippedMessage() {
46  return 'comments already migrated.';
47  }
48 
49  protected function doDBUpdates() {
50  $this->migrateToTemp(
51  'revision', 'rev_id', 'rev_comment', 'revcomment_rev', 'revcomment_comment_id'
52  );
53  $this->migrate( 'archive', 'ar_id', 'ar_comment' );
54  $this->migrate( 'ipblocks', 'ipb_id', 'ipb_reason' );
55  $this->migrate( 'image', 'img_name', 'img_description' );
56  $this->migrate( 'oldimage', [ 'oi_name', 'oi_timestamp' ], 'oi_description' );
57  $this->migrate( 'filearchive', 'fa_id', 'fa_deleted_reason' );
58  $this->migrate( 'filearchive', 'fa_id', 'fa_description' );
59  $this->migrate( 'recentchanges', 'rc_id', 'rc_comment' );
60  $this->migrate( 'logging', 'log_id', 'log_comment' );
61  $this->migrate( 'protected_titles', [ 'pt_namespace', 'pt_title' ], 'pt_reason' );
62  return true;
63  }
64 
71  private function loadCommentIDs( IDatabase $dbw, array &$comments ) {
72  $count = 0;
73  $needComments = $comments;
74 
75  while ( true ) {
76  $where = [];
77  foreach ( $needComments as $need => $dummy ) {
78  $where[] = $dbw->makeList(
79  [
80  'comment_hash' => CommentStore::hash( $need, null ),
81  'comment_text' => $need,
82  ],
83  LIST_AND
84  );
85  }
86 
87  $res = $dbw->select(
88  'comment',
89  [ 'comment_id', 'comment_text' ],
90  [
91  $dbw->makeList( $where, LIST_OR ),
92  'comment_data' => null,
93  ],
94  __METHOD__
95  );
96  foreach ( $res as $row ) {
97  $comments[$row->comment_text] = $row->comment_id;
98  unset( $needComments[$row->comment_text] );
99  }
100 
101  if ( !$needComments ) {
102  break;
103  }
104 
105  $dbw->insert(
106  'comment',
107  array_map( function ( $v ) {
108  return [
109  'comment_hash' => CommentStore::hash( $v, null ),
110  'comment_text' => $v,
111  ];
112  }, array_keys( $needComments ) ),
113  __METHOD__
114  );
115  $count += $dbw->affectedRows();
116  }
117  return $count;
118  }
119 
131  protected function migrate( $table, $primaryKey, $oldField ) {
132  $dbw = $this->getDB( DB_MASTER );
133  if ( !$dbw->fieldExists( $table, $oldField, __METHOD__ ) ) {
134  $this->output( "No need to migrate $table.$oldField, field does not exist\n" );
135  return;
136  }
137 
138  $newField = $oldField . '_id';
139  $primaryKey = (array)$primaryKey;
140  $pkFilter = array_flip( $primaryKey );
141  $this->output( "Beginning migration of $table.$oldField to $table.$newField\n" );
142  wfWaitForSlaves();
143 
144  $next = '1=1';
145  $countUpdated = 0;
146  $countComments = 0;
147  while ( true ) {
148  // Fetch the rows needing update
149  $res = $dbw->select(
150  $table,
151  array_merge( $primaryKey, [ $oldField ] ),
152  [
153  $newField => 0,
154  $next,
155  ],
156  __METHOD__,
157  [
158  'ORDER BY' => $primaryKey,
159  'LIMIT' => $this->getBatchSize(),
160  ]
161  );
162  if ( !$res->numRows() ) {
163  break;
164  }
165 
166  // Collect the distinct comments from those rows
167  $comments = [];
168  foreach ( $res as $row ) {
169  $comments[$row->$oldField] = 0;
170  }
171  $countComments += $this->loadCommentIDs( $dbw, $comments );
172 
173  // Update the existing rows
174  foreach ( $res as $row ) {
175  $dbw->update(
176  $table,
177  [
178  $newField => $comments[$row->$oldField],
179  $oldField => '',
180  ],
181  array_intersect_key( (array)$row, $pkFilter ) + [
182  $newField => 0
183  ],
184  __METHOD__
185  );
186  $countUpdated += $dbw->affectedRows();
187  }
188 
189  // Calculate the "next" condition
190  $next = '';
191  $prompt = [];
192  for ( $i = count( $primaryKey ) - 1; $i >= 0; $i-- ) {
193  $field = $primaryKey[$i];
194  $prompt[] = $row->$field;
195  $value = $dbw->addQuotes( $row->$field );
196  if ( $next === '' ) {
197  $next = "$field > $value";
198  } else {
199  $next = "$field > $value OR $field = $value AND ($next)";
200  }
201  }
202  $prompt = implode( ' ', array_reverse( $prompt ) );
203  $this->output( "... $prompt\n" );
204  wfWaitForSlaves();
205  }
206 
207  $this->output(
208  "Completed migration, updated $countUpdated row(s) with $countComments new comment(s)\n"
209  );
210  }
211 
227  protected function migrateToTemp( $table, $primaryKey, $oldField, $newPrimaryKey, $newField ) {
228  $dbw = $this->getDB( DB_MASTER );
229  if ( !$dbw->fieldExists( $table, $oldField, __METHOD__ ) ) {
230  $this->output( "No need to migrate $table.$oldField, field does not exist\n" );
231  return;
232  }
233 
234  $newTable = $table . '_comment_temp';
235  $this->output( "Beginning migration of $table.$oldField to $newTable.$newField\n" );
236  wfWaitForSlaves();
237 
238  $dbw = $this->getDB( DB_MASTER );
239  $next = [];
240  $countUpdated = 0;
241  $countComments = 0;
242  while ( true ) {
243  // Fetch the rows needing update
244  $res = $dbw->select(
245  [ $table, $newTable ],
246  [ $primaryKey, $oldField ],
247  [ $newPrimaryKey => null ] + $next,
248  __METHOD__,
249  [
250  'ORDER BY' => $primaryKey,
251  'LIMIT' => $this->getBatchSize(),
252  ],
253  [ $newTable => [ 'LEFT JOIN', "{$primaryKey}={$newPrimaryKey}" ] ]
254  );
255  if ( !$res->numRows() ) {
256  break;
257  }
258 
259  // Collect the distinct comments from those rows
260  $comments = [];
261  foreach ( $res as $row ) {
262  $comments[$row->$oldField] = 0;
263  }
264  $countComments += $this->loadCommentIDs( $dbw, $comments );
265 
266  // Update rows
267  $inserts = [];
268  $updates = [];
269  foreach ( $res as $row ) {
270  $inserts[] = [
271  $newPrimaryKey => $row->$primaryKey,
272  $newField => $comments[$row->$oldField]
273  ];
274  $updates[] = $row->$primaryKey;
275  }
276  $this->beginTransaction( $dbw, __METHOD__ );
277  $dbw->insert( $newTable, $inserts, __METHOD__ );
278  $dbw->update( $table, [ $oldField => '' ], [ $primaryKey => $updates ], __METHOD__ );
279  $countUpdated += $dbw->affectedRows();
280  $this->commitTransaction( $dbw, __METHOD__ );
281 
282  // Calculate the "next" condition
283  $next = [ $primaryKey . ' > ' . $dbw->addQuotes( $row->$primaryKey ) ];
284  $this->output( "... {$row->$primaryKey}\n" );
285  }
286 
287  $this->output(
288  "Completed migration, updated $countUpdated row(s) with $countComments new comment(s)\n"
289  );
290  }
291 }
292 
294 require_once RUN_MAINTENANCE_IF_MAIN;
commitTransaction(IDatabase $dbw, $fname)
Commit the transcation on a DB handle and wait for replica DBs to catch up.
affectedRows()
Get the number of rows affected by the last write query.
Apache License January AND DISTRIBUTION Definitions License shall mean the terms and conditions for use
migrate( $table, $primaryKey, $oldField)
Migrate comments in a table.
insert( $table, $a, $fname=__METHOD__, $options=[])
INSERT wrapper, inserts an array into a table.
$value
static hash( $text, $data)
Hashing function for comment storage.
setBatchSize( $s=0)
Set the batch size.
require_once RUN_MAINTENANCE_IF_MAIN
Definition: maintenance.txt:50
$maintClass
const DB_MASTER
Definition: defines.php:26
const LIST_AND
Definition: Defines.php:39
$res
Definition: database.txt:21
wfWaitForSlaves( $ifWritesSince=null, $wiki=false, $cluster=false, $timeout=null)
Waits for the replica DBs to catch up to the master position.
addDescription( $text)
Set the description text.
this hook is for auditing only or null if authentication failed before getting that far or null if we can t even determine that When $user is not null
Definition: hooks.txt:773
output( $out, $channel=null)
Throw some output to the user.
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
Definition: distributors.txt:9
const LIST_OR
Definition: Defines.php:42
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:35
migrateToTemp( $table, $primaryKey, $oldField, $newPrimaryKey, $newField)
Migrate comments in a table to a temporary table.
Class for scripts that perform database maintenance and want to log the update in updatelog so we can...
Basic database interface for live and lazy-loaded relation database handles.
Definition: IDatabase.php:38
you have access to all of the normal MediaWiki so you can get a DB use the etc For full docs on the Maintenance class
Definition: maintenance.txt:52
makeList( $a, $mode=self::LIST_COMMA)
Makes an encoded list of strings from an array.
getBatchSize()
Returns batch size.
select( $table, $vars, $conds='', $fname=__METHOD__, $options=[], $join_conds=[])
Execute a SELECT query constructed using the various parameters provided.
loadCommentIDs(IDatabase $dbw, array &$comments)
Fetch comment IDs for a set of comments.
getDB( $db, $groups=[], $dbDomain=false)
Returns a database to be used by current maintenance script.
Maintenance script that migrates comments from pre-1.30 columns to the &#39;comment&#39; table.
beginTransaction(IDatabase $dbw, $fname)
Begin a transcation on a DB.