MediaWiki  master
SamplingStatsdClient.php
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1 <?php
26 
32 class SamplingStatsdClient extends StatsdClient {
33  protected $samplingRates = [];
34 
42  public function setSamplingRates( array $samplingRates ) {
43  $this->samplingRates = $samplingRates;
44  }
45 
52  public function appendSampleRate( $data, $sampleRate = 1 ) {
54  if ( !$samplingRates && $sampleRate !== 1 ) {
55  $samplingRates = [ '*' => $sampleRate ];
56  }
57  if ( $samplingRates ) {
58  array_walk( $data, function ( $item ) use ( $samplingRates ) {
60  foreach ( $samplingRates as $pattern => $rate ) {
61  if ( fnmatch( $pattern, $item->getKey(), FNM_NOESCAPE ) ) {
62  $item->setSampleRate( $item->getSampleRate() * $rate );
63  break;
64  }
65  }
66  } );
67  }
68 
69  return $data;
70  }
71 
82  public function send( $data, $sampleRate = 1 ) {
83  if ( !is_array( $data ) ) {
84  $data = [ $data ];
85  }
86  if ( !$data ) {
87  return;
88  }
89  foreach ( $data as $item ) {
90  if ( !( $item instanceof StatsdDataInterface ) ) {
91  throw new InvalidArgumentException(
92  'SamplingStatsdClient does not accept stringified messages' );
93  }
94  }
95 
96  // add sampling
97  $data = $this->appendSampleRate( $data, $sampleRate );
98  $data = $this->sampleData( $data );
99 
100  $data = array_map( 'strval', $data );
101 
102  // reduce number of packets
103  if ( $this->getReducePacket() ) {
104  $data = $this->reduceCount( $data );
105  }
106 
107  // failures in any of this should be silently ignored if ..
108  $written = 0;
109  try {
110  $fp = $this->getSender()->open();
111  if ( !$fp ) {
112  return;
113  }
114  foreach ( $data as $message ) {
115  $written += $this->getSender()->write( $fp, $message );
116  }
117  $this->getSender()->close( $fp );
118  } catch ( Exception $e ) {
119  $this->throwException( $e );
120  }
121 
122  return $written;
123  }
124 
131  protected function sampleData( $data ) {
132  $newData = [];
133  $mt_rand_max = mt_getrandmax();
134  foreach ( $data as $item ) {
135  $samplingRate = $item->getSampleRate();
136  if ( $samplingRate <= 0.0 || $samplingRate > 1.0 ) {
137  throw new LogicException( 'Sampling rate shall be within ]0, 1]' );
138  }
139  if (
140  $samplingRate === 1 ||
141  ( mt_rand() / $mt_rand_max <= $samplingRate )
142  ) {
143  $newData[] = $item;
144  }
145  }
146  return $newData;
147  }
148 
152  protected function throwException( Exception $exception ) {
153  if ( !$this->getFailSilently() ) {
154  throw $exception;
155  }
156  }
157 }
setSamplingRates(array $samplingRates)
Sampling rates as an associative array of patterns and rates.
sampleData( $data)
Throw away some of the data according to the sample rate.
send( $data, $sampleRate=1)
Send the metrics over UDP Sample the metrics according to their sample rate and send the remaining on...
A statsd client that applies the sampling rate to the data items before sending them.
appendSampleRate( $data, $sampleRate=1)
Sets sampling rate for all items in $data.
Apache License January AND DISTRIBUTION Definitions License shall mean the terms and conditions for use
div flags Integer display flags(NO_ACTION_LINK, NO_EXTRA_USER_LINKS) 'LogException' returning false will NOT prevent logging $e
Definition: hooks.txt:2159
throwException(Exception $exception)
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
injection txt This is an overview of how MediaWiki makes use of dependency injection The design described here grew from the discussion of RFC T384 The term dependency this means that anything an object needs to operate should be injected from the the object itself should only know narrow no concrete implementation of the logic it relies on The requirement to inject everything typically results in an architecture that based on two main types of and essentially stateless service objects that use other service objects to operate on the value objects As of the beginning MediaWiki is only starting to use the DI approach Much of the code still relies on global state or direct resulting in a highly cyclical dependency which acts as the top level factory for services in MediaWiki which can be used to gain access to default instances of various services MediaWikiServices however also allows new services to be defined and default services to be redefined Services are defined or redefined by providing a callback the instantiator that will return a new instance of the service When it will create an instance of MediaWikiServices and populate it with the services defined in the files listed by thereby bootstrapping the DI framework Per $wgServiceWiringFiles lists includes ServiceWiring php
Definition: injection.txt:35