includes/search/SearchIndexField.php

   1 <?php
   2 /**
   3  * Definition of a mapping for the search index field.
   4  *
   5  * Must not be implemented directly by extensions, extend SearchIndexFieldDefinition instead.
   6  *
   7  * @stable to type
   8  * @since 1.28
   9  */
  10 interface SearchIndexField {
  11         /*
  12          * Field types
  13          */
  14         /**
  15          * TEXT fields are suitable for natural language and may be subject to
  16          * analysis such as stemming.
  17          *
  18          * Read more:
  19          * https://wikimediafoundation.org/2018/08/07/anatomy-search-token-affection/
  20          * https://wikimediafoundation.org/2018/09/13/anatomy-search-variation-under-nature/
  21          */
  22         public const INDEX_TYPE_TEXT = 'text';
  23         /**
  24          * KEYWORD fields are indexed without any processing, so are appropriate
  25          * for e.g. URLs.  The content will often consist of a single token.
  26          */
  27         public const INDEX_TYPE_KEYWORD = 'keyword';
  28         public const INDEX_TYPE_INTEGER = 'integer';
  29         public const INDEX_TYPE_NUMBER = 'number';
  30         public const INDEX_TYPE_DATETIME = 'datetime';
  31         public const INDEX_TYPE_NESTED = 'nested';
  32         public const INDEX_TYPE_BOOL = 'bool';
  33
  34         /**
  35          * SHORT_TEXT is meant to be used with short text made of mostly ascii
  36          * technical information. Generally a language agnostic analysis chain
  37          * is used and aggressive splitting to increase recall.
  38          * E.g suited for mime/type
  39          */
  40         public const INDEX_TYPE_SHORT_TEXT = 'short_text';
  41
  42         /**
  43          * Generic field flags.
  44          */
  45         /**
  46          * This field is case-insensitive.
  47          */
  48         public const FLAG_CASEFOLD = 1;
  49
  50         /**
  51          * This field contains secondary information, which is
  52          * already present in other fields, but can be used for
  53          * scoring.
  54          */
  55         public const FLAG_SCORING = 2;
  56
  57         /**
  58          * This field does not need highlight handling.
  59          */
  60         public const FLAG_NO_HIGHLIGHT = 4;
  61
  62         /**
  63          * Do not index this field, just store it.
  64          */
  65         public const FLAG_NO_INDEX = 8;
  66
  67         /**
  68          * Get mapping for specific search engine
  69          * @param SearchEngine $engine
  70          * @return array|null Null means this field does not map to anything
  71          */
  72         public function getMapping( SearchEngine $engine );
  73
  74         /**
  75          * Set global flag for this field.
  76          *
  77          * @param int $flag Bit flag to set/unset
  78          * @param bool $unset True if flag should be unset, false by default
  79          * @return $this
  80          */
  81         public function setFlag( $flag, $unset = false );
  82
  83         /**
  84          * Check if flag is set.
  85          * @param int $flag
  86          * @return int 0 if unset, !=0 if set
  87          */
  88         public function checkFlag( $flag );
  89
  90         /**
  91          * Merge two field definitions if possible.
  92          *
  93          * @param SearchIndexField $that
  94          * @return SearchIndexField|false New definition or false if not mergeable.
  95          */
  96         public function merge( SearchIndexField $that );
  97
  98         /**
  99          * A list of search engine hints for this field.
 100          * Hints are usually specific to a search engine implementation
 101          * and allow to fine control how the search engine will handle this
 102          * particular field.
 103          *
 104          * For example some search engine permits some optimizations
 105          * at index time by ignoring an update if the updated value
 106          * does not change by more than X% on a numeric value.
 107          *
 108          * @param SearchEngine $engine
 109          * @return array an array of hints generally indexed by hint name. The type of
 110          * values is search engine specific
 111          * @since 1.30
 112          */
 113         public function getEngineHints( SearchEngine $engine );
 114 }