MediaWiki  1.23.2
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1 <?php
24 if ( PHP_SAPI != 'cli-server' ) {
25  die( "This script can only be run by php's cli-server sapi." );
26 }
28 ini_set( 'display_errors', 1 );
29 error_reporting( E_ALL );
31 if ( isset( $_SERVER["SCRIPT_FILENAME"] ) ) {
32  # Known resource, sometimes a script sometimes a file
33  $file = $_SERVER["SCRIPT_FILENAME"];
34 } elseif ( isset( $_SERVER["SCRIPT_NAME"] ) ) {
35  # Usually unknown, document root relative rather than absolute
36  # Happens with some cases like /wiki/File:Image.png
37  if ( is_readable( $_SERVER['DOCUMENT_ROOT'] . $_SERVER["SCRIPT_NAME"] ) ) {
38  # Just in case this actually IS a file, set it here
40  } else {
41  # Otherwise let's pretend that this is supposed to go to index.php
42  $file = $_SERVER['DOCUMENT_ROOT'] . '/index.php';
43  }
44 } else {
45  # Meh, we'll just give up
46  return false;
47 }
49 # And now do handling for that $file
51 if ( !is_readable( $file ) ) {
52  # Let the server throw the error if it doesn't exist
53  return false;
54 }
55 $ext = pathinfo( $file, PATHINFO_EXTENSION );
56 if ( $ext == 'php' || $ext == 'php5' ) {
57  # Execute php files
58  # We use require and return true here because when you return false
59  # the php webserver will discard post data and things like login
60  # will not function in the dev environment.
61  require $file;
62  return true;
63 }
64 $mime = false;
65 $lines = explode( "\n", file_get_contents( "includes/mime.types" ) );
66 foreach ( $lines as $line ) {
67  $exts = explode( " ", $line );
68  $mime = array_shift( $exts );
69  if ( in_array( $ext, $exts ) ) {
70  break; # this is the right value for $mime
71  }
72  $mime = false;
73 }
74 if ( !$mime ) {
75  $basename = basename( $file );
76  if ( $basename == strtoupper( $basename ) ) {
77  # IF it's something like README serve it as text
78  $mime = "text/plain";
79  }
80 }
81 if ( $mime ) {
82  # Use custom handling to serve files with a known mime type
83  # This way we can serve things like .svg files that the built-in
84  # PHP webserver doesn't understand.
85  # ;) Nicely enough we just happen to bundle a mime.types file
86  $f = fopen( $file, 'rb' );
87  if ( preg_match( '#^text/#', $mime ) ) {
88  # Text should have a charset=UTF-8 (php's webserver does this too)
89  header( "Content-Type: $mime; charset=UTF-8" );
90  } else {
91  header( "Content-Type: $mime" );
92  }
93  header( "Content-Length: " . filesize( $file ) );
94  // Stream that out to the browser
95  fpassthru( $f );
96  return true;
97 }
99 # Let the php server handle things on it's own otherwise
100 return false;
skin txt MediaWiki includes four core it has been set as the default in MediaWiki since the replacing Monobook it had been been the default skin since before being replaced by Vector largely rewritten in while keeping its appearance Several legacy skins were removed in the as the burden of supporting them became too heavy to bear Those in etc for skin dependent CSS etc for skin dependent JavaScript These can also be customised on a per user by etc This feature has led to a wide variety of user styles becoming that gallery is a good place to ending in php
Definition: skin.txt:62
We use the convention $dbr for read and $dbw for write to help you keep track of whether the database object is a the world will explode Or to be a subsequent write query which succeeded on the master may fail when replicated to the slave due to a unique key collision Replication on the slave will stop and it may take hours to repair the database and get it back online Setting read_only in my cnf on the slave will avoid this but given the dire we prefer to have as many checks as possible We provide a but the wrapper functions like please read the documentation for except in special pages derived from QueryPage It s a common pitfall for new developers to submit code containing SQL queries which examine huge numbers of rows Remember that COUNT * is(N), counting rows in atable is like counting beans in a bucket.------------------------------------------------------------------------ Replication------------------------------------------------------------------------The largest installation of MediaWiki, Wikimedia, uses a large set ofslave MySQL servers replicating writes made to a master MySQL server. Itis important to understand the issues associated with this setup if youwant to write code destined for Wikipedia.It 's often the case that the best algorithm to use for a given taskdepends on whether or not replication is in use. Due to our unabashedWikipedia-centrism, we often just use the replication-friendly version, but if you like, you can use wfGetLB() ->getServerCount() > 1 tocheck to see if replication is in use.===Lag===Lag primarily occurs when large write queries are sent to the master.Writes on the master are executed in parallel, but they are executed inserial when they are replicated to the slaves. The master writes thequery to the binlog when the transaction is committed. The slaves pollthe binlog and start executing the query as soon as it appears. They canservice reads while they are performing a write query, but will not readanything more from the binlog and thus will perform no more writes. Thismeans that if the write query runs for a long time, the slaves will lagbehind the master for the time it takes for the write query to complete.Lag can be exacerbated by high read load. MediaWiki 's load balancer willstop sending reads to a slave when it is lagged by more than 30 seconds.If the load ratios are set incorrectly, or if there is too much loadgenerally, this may lead to a slave permanently hovering around 30seconds lag.If all slaves are lagged by more than 30 seconds, MediaWiki will stopwriting to the database. All edits and other write operations will berefused, with an error returned to the user. This gives the slaves achance to catch up. Before we had this mechanism, the slaves wouldregularly lag by several minutes, making review of recent editsdifficult.In addition to this, MediaWiki attempts to ensure that the user seesevents occurring on the wiki in chronological order. A few seconds of lagcan be tolerated, as long as the user sees a consistent picture fromsubsequent requests. This is done by saving the master binlog positionin the session, and then at the start of each request, waiting for theslave to catch up to that position before doing any reads from it. Ifthis wait times out, reads are allowed anyway, but the request isconsidered to be in "lagged slave mode". Lagged slave mode can bechecked by calling wfGetLB() ->getLaggedSlaveMode(). The onlypractical consequence at present is a warning displayed in the pagefooter.===Lag avoidance===To avoid excessive lag, queries which write large numbers of rows shouldbe split up, generally to write one row at a time. Multi-row INSERT ...SELECT queries are the worst offenders should be avoided altogether.Instead do the select first and then the insert.===Working with lag===Despite our best efforts, it 's not practical to guarantee a low-lagenvironment. Lag will usually be less than one second, but mayoccasionally be up to 30 seconds. For scalability, it 's very importantto keep load on the master low, so simply sending all your queries tothe master is not the answer. So when you have a genuine need forup-to-date data, the following approach is advised:1) Do a quick query to the master for a sequence number or timestamp 2) Run the full query on the slave and check if it matches the data you gotfrom the master 3) If it doesn 't, run the full query on the masterTo avoid swamping the master every time the slaves lag, use of thisapproach should be kept to a minimum. In most cases you should just readfrom the slave and let the user deal with the delay.------------------------------------------------------------------------ Lock contention------------------------------------------------------------------------Due to the high write rate on Wikipedia(and some other wikis), MediaWiki developers need to be very careful to structure their writesto avoid long-lasting locks. By default, MediaWiki opens a transactionat the first query, and commits it before the output is sent. Locks willbe held from the time when the query is done until the commit. So youcan reduce lock time by doing as much processing as possible before youdo your write queries.Often this approach is not good enough, and it becomes necessary toenclose small groups of queries in their own transaction. Use thefollowing syntax:$dbw=wfGetDB(DB_MASTER
Definition: UtfNormalTest2.php:38
Definition: router.php:65
if( $ext=='php'|| $ext=='php5') $mime
Definition: router.php:64
Definition: cdb.php:57
if(PHP_SAPI !='cli') $file
Definition: UtfNormalTest2.php:30
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
Definition: router.php:55