wikimedia/mediawiki-extensions-CirrusSearch

View on GitHub
maintenance/CheckIndexes.php

Summary

Maintainability
B
4 hrs
Test Coverage
<?php

namespace CirrusSearch\Maintenance;

use CirrusSearch\MetaStore\MetaStoreIndex;

/**
 * Check that all Cirrus indexes report OK.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 * http://www.gnu.org/copyleft/gpl.html
 */

$IP = getenv( 'MW_INSTALL_PATH' );
if ( $IP === false ) {
    $IP = __DIR__ . '/../../..';
}
require_once "$IP/maintenance/Maintenance.php";
require_once __DIR__ . '/../includes/Maintenance/Maintenance.php';

class CheckIndexes extends Maintenance {
    /**
     * @var array[] Nested array of arrays containing error strings. Individual
     *  errors are nested based on the keys in self::$path at the time the error
     *  occurred.
     */
    private $errors = [];
    /**
     * @var string[] Represents each step of current indentation level
     */
    private $path;
    /**
     * @var array Result of querying elasticsearch _cluster/state api endpoint
     */
    private $clusterState;
    /**
     * @var array[] Version info stored in elasticsearch /mw_cirrus_versions/version
     */
    private $cirrusInfo;

    public function __construct() {
        parent::__construct();
        $this->addDescription( 'Check that all Cirrus indexes report OK. This always operates on ' .
            'a single cluster.' );

        $this->addOption( 'nagios', 'Output in nagios format' );
    }

    public function execute() {
        if ( $this->hasOption( 'nagios' ) ) {
            // Force silent running mode so we can match Nagios expected output.
            $this->mQuiet = true;
        }
        $this->requireCirrusReady();
        $this->ensureClusterStateFetched();
        $this->ensureCirrusInfoFetched();
        // @todo: use MetaStoreIndex
        $aliases = [];
        foreach ( $this->clusterState[ 'metadata' ][ 'indices' ] as $indexName => $data ) {
            foreach ( $data[ 'aliases' ] as $alias ) {
                $aliases[ $alias ][] = $indexName;
            }
        }
        $this->checkMetastore( $aliases );
        foreach ( $this->cirrusInfo as $alias => $data ) {
            foreach ( $aliases[ $alias ] as $indexName ) {
                $this->checkIndex( $indexName, $data[ 'shard_count'] );
            }
        }
        $indexCount = count( $this->cirrusInfo );
        $errCount = count( $this->errors );
        if ( $this->hasOption( 'nagios' ) ) {
            // Exit silent running mode so we can log Nagios style output
            $this->mQuiet = false;
            if ( $errCount > 0 ) {
                $this->output( "CIRRUSSEARCH CRITICAL - $indexCount indexes report $errCount errors\n" );
            } else {
                $this->output( "CIRRUSSEARCH OK - $indexCount indexes report 0 errors\n" );
            }
        }
        $this->printErrorRecursive( '', $this->errors );
        // If there are error use the nagios error codes to signal them
        if ( $errCount > 0 ) {
            die( 2 );
        }

        return true;
    }

    private function checkMetastore( array $aliases ) {
        $this->in( MetaStoreIndex::INDEX_NAME );
        if ( isset( $aliases[ MetaStoreIndex::INDEX_NAME ] ) ) {
            $this->check( 'alias count', 1, count( $aliases[ MetaStoreIndex::INDEX_NAME ] ) );
            foreach ( $aliases[ MetaStoreIndex::INDEX_NAME ] as $indexName ) {
                $this->checkIndex( $indexName, 1 );
            }
        } else {
            $this->err( 'does not exist' );
        }
        $this->out();
    }

    /**
     * @param string $indexName
     * @param int $expectedShardCount
     */
    private function checkIndex( $indexName, $expectedShardCount ) {
        $metadata = $this->getIndexMetadata( $indexName );
        $this->in( $indexName );
        if ( $metadata === null ) {
            $this->err( 'does not exist' );
            $this->out();
            return;
        }
        $this->check( 'state', 'open', $metadata[ 'state' ] );
        // TODO check aliases

        $routingTable = $this->getIndexRoutingTable( $indexName );
        $this->check( 'shard count', $expectedShardCount, count( $routingTable[ 'shards' ] ) );
        foreach ( $routingTable[ 'shards' ] as $shardIndex => $shardRoutingTable ) {
            $this->in( "shard $shardIndex" );
            foreach ( $shardRoutingTable as $replicaIndex => $replica ) {
                $this->in( "replica $replicaIndex" );
                $this->check( 'state', [ 'STARTED', 'RELOCATING' ], $replica[ 'state' ] );
                $this->out();
            }
            $this->out();
        }
        $this->out();
    }

    /**
     * @param string $header
     */
    private function in( $header ) {
        $this->path[] = $header;
        $this->output( str_repeat( "\t", count( $this->path ) - 1 ) );
        $this->output( "$header...\n" );
    }

    private function out() {
        array_pop( $this->path );
    }

    /**
     * @param string $name
     * @param mixed $expected
     * @param mixed $actual
     */
    private function check( $name, $expected, $actual ) {
        $this->output( str_repeat( "\t", count( $this->path ) ) );
        $this->output( "$name..." );
        if ( is_array( $expected ) ) {
            if ( in_array( $actual, $expected ) ) {
                $this->output( "ok\n" );
            } else {
                $expectedStr = implode( ', ', $expected );
                $this->output( "$actual not in [$expectedStr]\n" );
                $this->err( "expected $name to be in [$expectedStr] but was $actual" );
            }
        } else {
            if ( $expected === $actual ) {
                $this->output( "ok\n" );
            } else {
                $this->output( "$expected != $actual\n" );
                $this->err( "expected $name to be '$expected' but was '$actual'" );
            }
        }
    }

    /**
     * @param string $explanation
     */
    private function err( $explanation ) {
        $e = &$this->errors;
        foreach ( $this->path as $element ) {
            $e = &$e[ $element ];
        }
        $e[] = $explanation;
    }

    /**
     * @param string $indent Prefix to attach before each line of output
     * @param array $array
     */
    private function printErrorRecursive( $indent, array $array ) {
        foreach ( $array as $key => $value ) {
            $line = $indent;
            if ( !is_numeric( $key ) ) {
                $line .= "$key...";
            }
            if ( is_array( $value ) ) {
                $this->error( $line );
                $this->printErrorRecursive( "$indent\t", $value );
            } else {
                $line .= $value;
                if ( $this->hasOption( 'nagios' ) ) {
                    $this->output( "$line\n" );
                } else {
                    $this->error( $line );
                }
            }
        }
    }

    /**
     * @param string $indexName fully qualified name of elasticsearch index
     * @return array|null Index metadata from elasticsearch cluster state
     */
    private function getIndexMetadata( $indexName ) {
        return $this->clusterState['metadata']['indices'][$indexName] ?? null;
    }

    /**
     * @param string $indexName fully qualified name of elasticsearch index
     * @return array
     */
    private function getIndexRoutingTable( $indexName ) {
        return $this->clusterState[ 'routing_table' ][ 'indices' ][ $indexName ];
    }

    private function ensureClusterStateFetched() {
        if ( $this->clusterState === null ) {
            $this->clusterState = $this->getConnection()->getClient()
                ->request( '_cluster/state' )->getData();
        }
    }

    private function ensureCirrusInfoFetched() {
        if ( $this->cirrusInfo === null ) {
            $store = $this->getMetaStore()->versionStore();
            $this->cirrusInfo = [];
            foreach ( $store->findAll() as $r ) {
                $data = $r->getData();
                $this->cirrusInfo[ $data['index_name'] ] = [
                    'shard_count' => $data[ 'shard_count' ],
                ];
            }
        }
    }
}

$maintClass = CheckIndexes::class;
require_once RUN_MAINTENANCE_IF_MAIN;