includes/Timestamp.php

   1 <?php
   2 /**
   3  * Creation and parsing of MW-style timestamps.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @since 1.20
  22  * @author Tyler Romeo, 2012
  23  */
  24
  25 /**
  26  * Library for creating and parsing MW-style timestamps. Based on the JS
  27  * library that does the same thing.
  28  *
  29  * @since 1.20
  30  */
  31 class MWTimestamp {
  32         /**
  33          * Standard gmdate() formats for the different timestamp types.
  34          */
  35         private static $formats = array(
  36                 TS_UNIX => 'U',
  37                 TS_MW => 'YmdHis',
  38                 TS_DB => 'Y-m-d H:i:s',
  39                 TS_ISO_8601 => 'Y-m-d\TH:i:s\Z',
  40                 TS_ISO_8601_BASIC => 'Ymd\THis\Z',
  41                 TS_EXIF => 'Y:m:d H:i:s', // This shouldn't ever be used, but is included for completeness
  42                 TS_RFC2822 => 'D, d M Y H:i:s',
  43                 TS_ORACLE => 'd-m-Y H:i:s.000000', // Was 'd-M-y h.i.s A' . ' +00:00' before r51500
  44                 TS_POSTGRES => 'Y-m-d H:i:s',
  45         );
  46
  47         /**
  48          * Different units for human readable timestamps.
  49          * @see MWTimestamp::getHumanTimestamp
  50          */
  51         private static $units = array(
  52                 "milliseconds" => 1,
  53                 "seconds" => 1000, // 1000 milliseconds per second
  54                 "minutes" => 60, // 60 seconds per minute
  55                 "hours" => 60, // 60 minutes per hour
  56                 "days" => 24, // 24 hours per day
  57                 "months" => 30, // approximately 30 days per month
  58                 "years" => 12, // 12 months per year
  59         );
  60
  61         /**
  62          * The actual timestamp being wrapped. Either a DateTime
  63          * object or a string with a Unix timestamp depending on
  64          * PHP.
  65          * @var string|DateTime
  66          */
  67         private $timestamp;
  68
  69         /**
  70          * Make a new timestamp and set it to the specified time,
  71          * or the current time if unspecified.
  72          *
  73          * @since 1.20
  74          *
  75          * @param bool|string $timestamp Timestamp to set, or false for current time
  76          */
  77         public function __construct( $timestamp = false ) {
  78                 $this->setTimestamp( $timestamp );
  79         }
  80
  81         /**
  82          * Set the timestamp to the specified time, or the current time if unspecified.
  83          *
  84          * Parse the given timestamp into either a DateTime object or a Unix timestamp,
  85          * and then store it.
  86          *
  87          * @since 1.20
  88          *
  89          * @param string|bool $ts Timestamp to store, or false for now
  90          * @throws TimestampException
  91          */
  92         public function setTimestamp( $ts = false ) {
  93                 $da = array();
  94                 $strtime = '';
  95
  96                 if ( !$ts || $ts === "\0\0\0\0\0\0\0\0\0\0\0\0\0\0" ) { // We want to catch 0, '', null... but not date strings starting with a letter.
  97                         $uts = time();
  98                         $strtime = "@$uts";
  99                 } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
 100                         # TS_DB
 101                 } elseif ( preg_match( '/^(\d{4}):(\d\d):(\d\d) (\d\d):(\d\d):(\d\d)$/D', $ts, $da ) ) {
 102                         # TS_EXIF
 103                 } elseif ( preg_match( '/^(\d{4})(\d\d)(\d\d)(\d\d)(\d\d)(\d\d)$/D', $ts, $da ) ) {
 104                         # TS_MW
 105                 } elseif ( preg_match( '/^-?\d{1,13}$/D', $ts ) ) {
 106                         # TS_UNIX
 107                         $strtime = "@$ts"; // http://php.net/manual/en/datetime.formats.compound.php
 108                 } elseif ( preg_match( '/^\d{2}-\d{2}-\d{4} \d{2}:\d{2}:\d{2}.\d{6}$/', $ts ) ) {
 109                         # TS_ORACLE // session altered to DD-MM-YYYY HH24:MI:SS.FF6
 110                         $strtime = preg_replace( '/(\d\d)\.(\d\d)\.(\d\d)(\.(\d+))?/', "$1:$2:$3",
 111                                         str_replace( '+00:00', 'UTC', $ts ) );
 112                 } elseif ( preg_match( '/^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2})(?:\.*\d*)?Z$/', $ts, $da ) ) {
 113                         # TS_ISO_8601
 114                 } elseif ( preg_match( '/^(\d{4})(\d{2})(\d{2})T(\d{2})(\d{2})(\d{2})(?:\.*\d*)?Z$/', $ts, $da ) ) {
 115                         #TS_ISO_8601_BASIC
 116                 } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d*[\+\- ](\d\d)$/', $ts, $da ) ) {
 117                         # TS_POSTGRES
 118                 } elseif ( preg_match( '/^(\d{4})\-(\d\d)\-(\d\d) (\d\d):(\d\d):(\d\d)\.*\d* GMT$/', $ts, $da ) ) {
 119                         # TS_POSTGRES
 120                 } elseif ( preg_match( '/^[ \t\r\n]*([A-Z][a-z]{2},[ \t\r\n]*)?' . # Day of week
 121                                                                 '\d\d?[ \t\r\n]*[A-Z][a-z]{2}[ \t\r\n]*\d{2}(?:\d{2})?' .  # dd Mon yyyy
 122                                                                 '[ \t\r\n]*\d\d[ \t\r\n]*:[ \t\r\n]*\d\d[ \t\r\n]*:[ \t\r\n]*\d\d/S', $ts ) ) { # hh:mm:ss
 123                         # TS_RFC2822, accepting a trailing comment. See http://www.squid-cache.org/mail-archive/squid-users/200307/0122.html / r77171
 124                         # The regex is a superset of rfc2822 for readability
 125                         $strtime = strtok( $ts, ';' );
 126                 } elseif ( preg_match( '/^[A-Z][a-z]{5,8}, \d\d-[A-Z][a-z]{2}-\d{2} \d\d:\d\d:\d\d/', $ts ) ) {
 127                         # TS_RFC850
 128                         $strtime = $ts;
 129                 } elseif ( preg_match( '/^[A-Z][a-z]{2} [A-Z][a-z]{2} +\d{1,2} \d\d:\d\d:\d\d \d{4}/', $ts ) ) {
 130                         # asctime
 131                         $strtime = $ts;
 132                 } else {
 133                         throw new TimestampException( __METHOD__ . " : Invalid timestamp - $ts" );
 134                 }
 135
 136                 if( !$strtime ) {
 137                         $da = array_map( 'intval', $da );
 138                         $da[0] = "%04d-%02d-%02dT%02d:%02d:%02d.00+00:00";
 139                         $strtime = call_user_func_array( "sprintf", $da );
 140                 }
 141
 142                 try {
 143                         $final = new DateTime( $strtime, new DateTimeZone( 'GMT' ) );
 144                 } catch( Exception $e ) {
 145                         throw new TimestampException( __METHOD__ . ' Invalid timestamp format.' );
 146                 }
 147
 148                 if( $final === false ) {
 149                         throw new TimestampException( __METHOD__ . ' Invalid timestamp format.' );
 150                 }
 151                 $this->timestamp = $final;
 152         }
 153
 154         /**
 155          * Get the timestamp represented by this object in a certain form.
 156          *
 157          * Convert the internal timestamp to the specified format and then
 158          * return it.
 159          *
 160          * @since 1.20
 161          *
 162          * @param int $style Constant Output format for timestamp
 163          * @throws TimestampException
 164          * @return string The formatted timestamp
 165          */
 166         public function getTimestamp( $style = TS_UNIX ) {
 167                 if( !isset( self::$formats[$style] ) ) {
 168                         throw new TimestampException( __METHOD__ . ' : Illegal timestamp output type.' );
 169                 }
 170
 171                 if( is_object( $this->timestamp  ) ) {
 172                         // DateTime object was used, call DateTime::format.
 173                         $output = $this->timestamp->format( self::$formats[$style] );
 174                 } elseif( TS_UNIX == $style ) {
 175                         // Unix timestamp was used and is wanted, just return it.
 176                         $output = $this->timestamp;
 177                 } else {
 178                         // Unix timestamp was used, use gmdate().
 179                         $output = gmdate( self::$formats[$style], $this->timestamp );
 180                 }
 181
 182                 if ( ( $style == TS_RFC2822 ) || ( $style == TS_POSTGRES ) ) {
 183                         $output .= ' GMT';
 184                 }
 185
 186                 return $output;
 187         }
 188
 189         /**
 190          * Get the timestamp in a human-friendly relative format, e.g., "3 days ago".
 191          *
 192          * Determine the difference between the timestamp and the current time, and
 193          * generate a readable timestamp by returning "<N> <units> ago", where the
 194          * largest possible unit is used.
 195          *
 196          * @since 1.20
 197          *
 198          * @return Message Formatted timestamp
 199          */
 200         public function getHumanTimestamp() {
 201                 $then = $this->getTimestamp( TS_UNIX );
 202                 $now = time();
 203                 $timeago = ($now - $then) * 1000;
 204                 $message = false;
 205
 206                 foreach( self::$units as $unit => $factor ) {
 207                         $next = $timeago / $factor;
 208                         if( $next < 1 ) {
 209                                 break;
 210                         } else {
 211                                 $timeago = $next;
 212                                 $message = array( $unit, floor( $timeago ) );
 213                         }
 214                 }
 215
 216                 if( $message ) {
 217                         $initial = call_user_func_array( 'wfMessage', $message );
 218                         return wfMessage( 'ago', $initial->parse() );
 219                 } else {
 220                         return wfMessage( 'just-now' );
 221                 }
 222         }
 223
 224         /**
 225          * @since 1.20
 226          *
 227          * @return string
 228          */
 229         public function __toString() {
 230                 return $this->getTimestamp();
 231         }
 232 }
 233
 234 /**
 235  * @since 1.20
 236  */
 237 class TimestampException extends MWException {}