Code Coverage |
||||||||||
Lines |
Functions and Methods |
Classes and Traits |
||||||||
| Total | |
11.46% |
11 / 96 |
|
11.11% |
1 / 9 |
CRAP | |
0.00% |
0 / 1 |
| MWElasticUtils | |
11.58% |
11 / 95 |
|
11.11% |
1 / 9 |
457.06 | |
0.00% |
0 / 1 |
| withRetry | |
90.91% |
10 / 11 |
|
0.00% |
0 / 1 |
5.02 | |||
| backoffDelay | |
100.00% |
1 / 1 |
|
100.00% |
1 / 1 |
1 | |||
| getIndexHealth | |
0.00% |
0 / 6 |
|
0.00% |
0 / 1 |
6 | |||
| waitForGreen | |
0.00% |
0 / 12 |
|
0.00% |
0 / 1 |
20 | |||
| deleteByQuery | |
0.00% |
0 / 3 |
|
0.00% |
0 / 1 |
6 | |||
| increasingDelay | |
0.00% |
0 / 4 |
|
0.00% |
0 / 1 |
6 | |||
| deleteByQueryWithStatus | |
0.00% |
0 / 52 |
|
0.00% |
0 / 1 |
42 | |||
| fetchClusterName | |
0.00% |
0 / 5 |
|
0.00% |
0 / 1 |
6 | |||
| isFrozen | |
0.00% |
0 / 1 |
|
0.00% |
0 / 1 |
2 | |||
| 1 | <?php |
| 2 | |
| 3 | namespace MediaWiki\Extension\Elastica; |
| 4 | |
| 5 | use Elastica\Client; |
| 6 | use Elastica\Index; |
| 7 | use Elastica\Query; |
| 8 | use Elastica\Task; |
| 9 | use Elasticsearch\Endpoints\Cluster\Health; |
| 10 | use Exception; |
| 11 | use FormatJson; |
| 12 | use Generator; |
| 13 | use MediaWiki\Logger\LoggerFactory; |
| 14 | use MWTimestamp; |
| 15 | |
| 16 | /** |
| 17 | * This program is free software; you can redistribute it and/or modify |
| 18 | * it under the terms of the GNU General Public License as published by |
| 19 | * the Free Software Foundation; either version 2 of the License, or |
| 20 | * (at your option) any later version. |
| 21 | * |
| 22 | * This program is distributed in the hope that it will be useful, |
| 23 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 24 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 25 | * GNU General Public License for more details. |
| 26 | * |
| 27 | * You should have received a copy of the GNU General Public License along |
| 28 | * with this program; if not, write to the Free Software Foundation, Inc., |
| 29 | * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. |
| 30 | * |
| 31 | */ |
| 32 | |
| 33 | /** |
| 34 | * Utility class |
| 35 | */ |
| 36 | class MWElasticUtils { |
| 37 | |
| 38 | private const ONE_SEC_IN_MICROSEC = 1000000; |
| 39 | |
| 40 | /** |
| 41 | * A function that retries callback $func if it throws an exception. |
| 42 | * The $beforeRetry is called before a retry and receives the underlying |
| 43 | * ExceptionInterface object and the number of failed attempts. |
| 44 | * It's generally used to log and sleep between retries. Default behaviour |
| 45 | * is to sleep with a random backoff. |
| 46 | * @see Util::backoffDelay |
| 47 | * |
| 48 | * @param int $attempts the number of times we retry |
| 49 | * @param callable $func |
| 50 | * @param callable|null $beforeRetry function called before each retry |
| 51 | * @return mixed |
| 52 | */ |
| 53 | public static function withRetry( $attempts, $func, $beforeRetry = null ) { |
| 54 | $errors = 0; |
| 55 | while ( true ) { |
| 56 | if ( $errors < $attempts ) { |
| 57 | try { |
| 58 | return $func(); |
| 59 | } catch ( Exception $e ) { |
| 60 | $errors++; |
| 61 | if ( $beforeRetry ) { |
| 62 | $beforeRetry( $e, $errors ); |
| 63 | } else { |
| 64 | $seconds = static::backoffDelay( $errors ); |
| 65 | usleep( $seconds * self::ONE_SEC_IN_MICROSEC ); |
| 66 | } |
| 67 | } |
| 68 | } else { |
| 69 | return $func(); |
| 70 | } |
| 71 | } |
| 72 | } |
| 73 | |
| 74 | /** |
| 75 | * Backoff with lowest possible upper bound as 16 seconds. |
| 76 | * With the default maximum number of errors (5) this maxes out at 256 seconds. |
| 77 | * |
| 78 | * @param int $errorCount |
| 79 | * @return int |
| 80 | */ |
| 81 | public static function backoffDelay( $errorCount ) { |
| 82 | return rand( 1, (int)pow( 2, 3 + $errorCount ) ); |
| 83 | } |
| 84 | |
| 85 | /** |
| 86 | * Get index health |
| 87 | * |
| 88 | * @param Client $client |
| 89 | * @param string $indexName |
| 90 | * @return array the index health status |
| 91 | */ |
| 92 | public static function getIndexHealth( Client $client, $indexName ) { |
| 93 | $endpoint = new Health; |
| 94 | $endpoint->setIndex( $indexName ); |
| 95 | $response = $client->requestEndpoint( $endpoint ); |
| 96 | if ( $response->hasError() ) { |
| 97 | throw new \Exception( "Error while fetching index health status: " . $response->getError() ); |
| 98 | } |
| 99 | return $response->getData(); |
| 100 | } |
| 101 | |
| 102 | /** |
| 103 | * Wait for the index to go green |
| 104 | * |
| 105 | * @param Client $client |
| 106 | * @param string $indexName Name of index to wait for |
| 107 | * @param int $timeout In seconds |
| 108 | * @return Generator|string[]|bool Returns a generator. Generator yields |
| 109 | * string status messages. Generator return value is true if the index is |
| 110 | * green false otherwise. |
| 111 | */ |
| 112 | public static function waitForGreen( Client $client, $indexName, $timeout ) { |
| 113 | $startTime = time(); |
| 114 | while ( ( $startTime + $timeout ) > time() ) { |
| 115 | try { |
| 116 | $response = self::getIndexHealth( $client, $indexName ); |
| 117 | $status = $response['status'] ?? 'unknown'; |
| 118 | if ( $status === 'green' ) { |
| 119 | yield "\tGreen!"; |
| 120 | return true; |
| 121 | } |
| 122 | yield "\tIndex is $status retrying..."; |
| 123 | sleep( 5 ); |
| 124 | } catch ( \Exception $e ) { |
| 125 | yield "Error while waiting for green ({$e->getMessage()}), retrying..."; |
| 126 | } |
| 127 | } |
| 128 | return false; |
| 129 | } |
| 130 | |
| 131 | /** |
| 132 | * Delete docs by query and wait for it to complete via tasks api. |
| 133 | * |
| 134 | * @param Index $index the source index |
| 135 | * @param Query $query the query |
| 136 | * @param bool $allowConflicts When true documents updated since starting |
| 137 | * the query will not be deleted, and will not fail the delete-by-query. When |
| 138 | * false (default) the updated document will not be deleted and the delete-by-query |
| 139 | * will abort. Deletes are not transactional, some subset of matching documents |
| 140 | * will have been deleted. |
| 141 | * @param int $reportEveryNumSec Log task status on this interval of seconds |
| 142 | * @return Task Generator returns the Task instance on completion. |
| 143 | * @throws Exception when task reports failures |
| 144 | */ |
| 145 | public static function deleteByQuery( |
| 146 | Index $index, |
| 147 | Query $query, |
| 148 | $allowConflicts = false, |
| 149 | $reportEveryNumSec = 300 |
| 150 | ) { |
| 151 | $gen = self::deleteByQueryWithStatus( $index, $query, $allowConflicts, $reportEveryNumSec ); |
| 152 | // @phan-suppress-next-line PhanTypeNoAccessiblePropertiesForeach always a generator object |
| 153 | foreach ( $gen as $status ) { |
| 154 | // We don't need these status updates. But we need to iterate |
| 155 | // the generator until it is done. |
| 156 | } |
| 157 | return $gen->getReturn(); |
| 158 | } |
| 159 | |
| 160 | /** |
| 161 | * @param float $minDelay Starting value of generator |
| 162 | * @param float $maxDelay Maximum value to return |
| 163 | * @param float $increaseByRatio Increase by this ratio on each iteration, up to $maxDelay |
| 164 | * @return Generator|float[] Returns a generator. Generator yields floats between |
| 165 | * $minDelay and $maxDelay |
| 166 | * @suppress PhanInfiniteLoop |
| 167 | */ |
| 168 | private static function increasingDelay( $minDelay, $maxDelay, $increaseByRatio = 1.5 ) { |
| 169 | $delay = $minDelay; |
| 170 | while ( true ) { |
| 171 | yield $delay; |
| 172 | $delay = min( $delay * $increaseByRatio, $maxDelay ); |
| 173 | } |
| 174 | } |
| 175 | |
| 176 | /** |
| 177 | * Delete docs by query and wait for it to complete via tasks api. This |
| 178 | * method returns a generator which must be iterated on at least once |
| 179 | * or the deletion will not occur. |
| 180 | * |
| 181 | * Client code that doesn't care about the result or when the deleteByQuery |
| 182 | * completes are safe to call next( $gen ) a single time to start the deletion, |
| 183 | * and then throw away the generator. Note that logging about how long the task |
| 184 | * has been running will not be logged if the generator is not iterated. |
| 185 | * |
| 186 | * @param Index $index the source index |
| 187 | * @param Query $query the query |
| 188 | * @param bool $allowConflicts When true documents updated since starting |
| 189 | * the query will not be deleted, and will not fail the delete-by-query. When |
| 190 | * false (default) the updated document will not be deleted and the delete-by-query |
| 191 | * will abort. Deletes are not transactional, some subset of matching documents |
| 192 | * will have been deleted. |
| 193 | * @param int $reportEveryNumSec Log task status on this interval of seconds |
| 194 | * @return \Generator|array[]|\Elastica\Task Returns a generator. Generator yields |
| 195 | * arrays containing task status responses. Generator returns the Task instance |
| 196 | * on completion via Generator::getReturn. |
| 197 | * @throws Exception when task reports failures |
| 198 | */ |
| 199 | public static function deleteByQueryWithStatus( |
| 200 | Index $index, |
| 201 | Query $query, |
| 202 | $allowConflicts = false, |
| 203 | $reportEveryNumSec = 300 |
| 204 | ) { |
| 205 | $params = [ |
| 206 | 'wait_for_completion' => 'false', |
| 207 | 'scroll' => '15m', |
| 208 | ]; |
| 209 | if ( $allowConflicts ) { |
| 210 | $params['conflicts'] = 'proceed'; |
| 211 | } |
| 212 | $response = $index->deleteByQuery( $query, $params )->getData(); |
| 213 | if ( !isset( $response['task'] ) ) { |
| 214 | throw new \Exception( 'No task returned: ' . var_export( $response, true ) ); |
| 215 | } |
| 216 | $log = LoggerFactory::getInstance( 'Elastica' ); |
| 217 | $clusterName = self::fetchClusterName( $index->getClient() ); |
| 218 | $logContext = [ |
| 219 | 'index' => $index->getName(), |
| 220 | 'cluster' => $clusterName, |
| 221 | 'taskId' => $response['task'], |
| 222 | ]; |
| 223 | $logPrefix = 'deleteByQuery against [{index}] on cluster [{cluster}] with task id [{taskId}]'; |
| 224 | $log->info( "$logPrefix starting", $logContext + [ |
| 225 | 'elastic_query' => FormatJson::encode( $query->toArray() ) |
| 226 | ] ); |
| 227 | |
| 228 | // Log tasks running longer than 10 minutes to help track down job runner |
| 229 | // timeouts that occur after 20 minutes. T219234 |
| 230 | $start = MWTimestamp::time(); |
| 231 | $reportAfter = $start + $reportEveryNumSec; |
| 232 | $task = new \Elastica\Task( |
| 233 | $index->getClient(), |
| 234 | $response['task'] ); |
| 235 | $delay = self::increasingDelay( 0.05, 5 ); |
| 236 | while ( !$task->isCompleted() ) { |
| 237 | $now = MWTimestamp::time(); |
| 238 | if ( $now >= $reportAfter ) { |
| 239 | $reportAfter = $now + $reportEveryNumSec; |
| 240 | $log->warning( "$logPrefix still running after [{runtime}] seconds", $logContext + [ |
| 241 | 'runtime' => $now - $start, |
| 242 | // json encode to ensure we don't add a bunch of properties in |
| 243 | // logstash, we only really need the content and this will still be |
| 244 | // searchable. |
| 245 | 'status' => FormatJson::encode( $task->getData() ), |
| 246 | ] ); |
| 247 | } |
| 248 | yield $task->getData(); |
| 249 | $delay->next(); |
| 250 | usleep( $delay->current() * self::ONE_SEC_IN_MICROSEC ); |
| 251 | $task->refresh(); |
| 252 | } |
| 253 | |
| 254 | $now = MWTimestamp::time(); |
| 255 | $taskCompleteResponse = $task->getData()['response']; |
| 256 | if ( $taskCompleteResponse['failures'] ) { |
| 257 | $log->error( "$logPrefix failed", $logContext + [ |
| 258 | 'runtime' => $now - $start, |
| 259 | 'status' => FormatJson::encode( $task->getData() ), |
| 260 | ] ); |
| 261 | throw new \Exception( 'Failed deleteByQuery: ' |
| 262 | . implode( ', ', $taskCompleteResponse['failures'] ) ); |
| 263 | } |
| 264 | |
| 265 | $log->info( "$logPrefix completed", $logContext + [ |
| 266 | 'runtime' => $now - $start, |
| 267 | 'status' => FormatJson::encode( $task->getData() ), |
| 268 | ] ); |
| 269 | |
| 270 | return $task; |
| 271 | } |
| 272 | |
| 273 | /** |
| 274 | * Fetch the name of the cluster client is communicating with. |
| 275 | * |
| 276 | * @param Client $client Elasticsearch client to fetch name for |
| 277 | * @return string Name of cluster $client is communicating with |
| 278 | */ |
| 279 | public static function fetchClusterName( Client $client ) { |
| 280 | $response = $client->requestEndpoint( new \Elasticsearch\Endpoints\Info ); |
| 281 | if ( $response->getStatus() !== 200 ) { |
| 282 | throw new Exception( |
| 283 | "Failed requesting cluster name, got status code [{$response->getStatus()}]" ); |
| 284 | } |
| 285 | return $response->getData()['cluster_name']; |
| 286 | } |
| 287 | |
| 288 | /** |
| 289 | * @param Client $client |
| 290 | * @return bool True when no writes should be sent via $client |
| 291 | * @deprecated (always returns false) |
| 292 | */ |
| 293 | public static function isFrozen( Client $client ) { |
| 294 | return false; |
| 295 | } |
| 296 | } |
| 297 | |
| 298 | class_alias( MWElasticUtils::class, 'MWElasticUtils' ); |