includes/pager/RangeChronologicalPager.php

   1 <?php
   2 /**
   3  * This program is free software; you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License as published by
   5  * the Free Software Foundation; either version 2 of the License, or
   6  * (at your option) any later version.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along
  14  * with this program; if not, write to the Free Software Foundation, Inc.,
  15  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  16  * http://www.gnu.org/copyleft/gpl.html
  17  *
  18  * @file
  19  * @ingroup Pager
  20  */
  21 use Wikimedia\Timestamp\TimestampException;
  22
  23 /**
  24  * Pager for filtering by a range of dates.
  25  * @ingroup Pager
  26  */
  27 abstract class RangeChronologicalPager extends ReverseChronologicalPager {
  28
  29         protected $rangeConds = [];
  30
  31         /**
  32          * Set and return a date range condition using timestamps provided by the user.
  33          * We want the revisions between the two timestamps.
  34          * Also supports only having a start or end timestamp.
  35          * Assumes that the start timestamp comes before the end timestamp.
  36          *
  37          * @param string $startStamp Timestamp of the beginning of the date range (or empty)
  38          * @param string $endStamp Timestamp of the end of the date range (or empty)
  39          * @return array|null Database conditions to satisfy the specified date range
  40          *     or null if dates are invalid
  41          */
  42         public function getDateRangeCond( $startStamp, $endStamp ) {
  43                 $this->rangeConds = [];
  44
  45                 try {
  46                         if ( $startStamp !== '' ) {
  47                                 $startTimestamp = MWTimestamp::getInstance( $startStamp );
  48                                 $startOffset = $this->mDb->timestamp( $startTimestamp->getTimestamp() );
  49                                 $this->rangeConds[] = $this->mIndexField . '>=' . $this->mDb->addQuotes( $startOffset );
  50                         }
  51
  52                         if ( $endStamp !== '' ) {
  53                                 $endTimestamp = MWTimestamp::getInstance( $endStamp );
  54                                 $endOffset = $this->mDb->timestamp( $endTimestamp->getTimestamp() );
  55                                 $this->rangeConds[] = $this->mIndexField . '<=' . $this->mDb->addQuotes( $endOffset );
  56
  57                                 // populate existing variables for compatibility with parent
  58                                 $this->mYear = (int)$endTimestamp->format( 'Y' );
  59                                 $this->mMonth = (int)$endTimestamp->format( 'm' );
  60                                 $this->mDay = (int)$endTimestamp->format( 'd' );
  61                                 $this->mOffset = $endOffset;
  62                         }
  63                 } catch ( TimestampException $ex ) {
  64                         return null;
  65                 }
  66
  67                 return $this->rangeConds;
  68         }
  69
  70         /**
  71          * Takes ReverseChronologicalPager::getDateCond parameters and repurposes
  72          * them to work with timestamp-based getDateRangeCond.
  73          *
  74          * @param int $year Year up to which we want revisions
  75          * @param int $month Month up to which we want revisions
  76          * @param int $day [optional] Day up to which we want revisions. Default is end of month.
  77          * @return string|null Timestamp or null if year and month are false/invalid
  78          */
  79         public function getDateCond( $year, $month, $day = -1 ) {
  80                 // run through getDateRangeCond so rangeConds, mOffset, ... are set
  81                 $legacyTimestamp = self::getOffsetDate( $year, $month, $day );
  82                 // ReverseChronologicalPager uses strict inequality for the end date ('<'),
  83                 // but this class uses '<=' and expects extending classes to handle modifying the end date.
  84                 // Therefore, we need to subtract one second from the output of getOffsetDate to make it
  85                 // work with the '<=' inequality used in this class.
  86                 $legacyTimestamp->timestamp = $legacyTimestamp->timestamp->modify( '-1 second' );
  87                 $this->getDateRangeCond( '', $legacyTimestamp->getTimestamp( TS_MW ) );
  88                 return $this->mOffset;
  89         }
  90
  91         /**
  92          * Build variables to use by the database wrapper.
  93          *
  94          * @param string $offset Index offset, inclusive
  95          * @param int $limit Exact query limit
  96          * @param bool $descending Query direction, false for ascending, true for descending
  97          * @return array
  98          */
  99         protected function buildQueryInfo( $offset, $limit, $descending ) {
 100                 list( $tables, $fields, $conds, $fname, $options, $join_conds ) = parent::buildQueryInfo(
 101                         $offset,
 102                         $limit,
 103                         $descending
 104                 );
 105
 106                 if ( $this->rangeConds ) {
 107                         $conds = array_merge( $conds, $this->rangeConds );
 108                 }
 109
 110                 return [ $tables, $fields, $conds, $fname, $options, $join_conds ];
 111         }
 112 }