Files
Nominatim/lib/TokenList.php
Sarah Hoffmann 0f87da017f improve handling of multi-word partials in SearchDescription
Multi-word partial terms had an undue advantage over separate partial
terms because they only need to pay the penalty once. This changes
the behaviour by setting the penalty according to the number of
words in the token. This should get rid of search interpretations
with low chance of matching.

This also fixes handling of exact term matching. We now match against
all exact terms of the query, not just a couple of them collected
while building the interpretations.

Also adds a penalty to very short postcodes.
2020-11-25 12:07:04 +01:00

217 lines
7.1 KiB
PHP

<?php
namespace Nominatim;
require_once(CONST_BasePath.'/lib/TokenCountry.php');
require_once(CONST_BasePath.'/lib/TokenHousenumber.php');
require_once(CONST_BasePath.'/lib/TokenPostcode.php');
require_once(CONST_BasePath.'/lib/TokenSpecialTerm.php');
require_once(CONST_BasePath.'/lib/TokenWord.php');
require_once(CONST_BasePath.'/lib/SpecialSearchOperator.php');
/**
* Saves information about the tokens that appear in a search query.
*
* Tokens are sorted by their normalized form, the token word. There are different
* kinds of tokens, represented by different Token* classes. Note that
* tokens do not have a common base class. All tokens need to have a field
* with the word id that points to an entry in the `word` database table
* but otherwise the information saved about a token can be very different.
*
* There are two different kinds of token words: full words and partial terms.
*
* Full words start with a space. They represent a complete name of a place.
* All special tokens are normally full words.
*
* Partial terms have no space at the beginning. They may represent a part of
* a name of a place (e.g. in the name 'World Trade Center' a partial term
* would be 'Trade' or 'Trade Center'). They are only used in TokenWord.
*/
class TokenList
{
// List of list of tokens indexed by their word_token.
private $aTokens = array();
/**
* Return total number of tokens.
*
* @return Integer
*/
public function count()
{
return count($this->aTokens);
}
/**
* Check if there are tokens for the given token word.
*
* @param string $sWord Token word to look for.
*
* @return bool True if there is one or more token for the token word.
*/
public function contains($sWord)
{
return isset($this->aTokens[$sWord]);
}
/**
* Check if there are partial or full tokens for the given word.
*
* @param string $sWord Token word to look for.
*
* @return bool True if there is one or more token for the token word.
*/
public function containsAny($sWord)
{
return isset($this->aTokens[$sWord]) || isset($this->aTokens[' '.$sWord]);
}
/**
* Get the list of tokens for the given token word.
*
* @param string $sWord Token word to look for.
*
* @return object[] Array of tokens for the given token word or an
* empty array if no tokens could be found.
*/
public function get($sWord)
{
return isset($this->aTokens[$sWord]) ? $this->aTokens[$sWord] : array();
}
public function getFullWordIDs()
{
$ids = array();
foreach($this->aTokens as $aTokenList) {
foreach($aTokenList as $oToken) {
if (is_a($oToken, '\Nominatim\Token\Word') && !$oToken->bPartial) {
$ids[$oToken->iId] = $oToken->iId;
}
}
}
return $ids;
}
/**
* Add token information from the word table in the database.
*
* @param object $oDB Nominatim::DB instance.
* @param string[] $aTokens List of tokens to look up in the database.
* @param string[] $aCountryCodes List of country restrictions.
* @param string $sNormQuery Normalized query string.
* @param object $oNormalizer Normalizer function to use on tokens.
*
* @return void
*/
public function addTokensFromDB(&$oDB, &$aTokens, &$aCountryCodes, $sNormQuery, $oNormalizer)
{
// Check which tokens we have, get the ID numbers
$sSQL = 'SELECT word_id, word_token, word, class, type, country_code,';
$sSQL .= ' operator, coalesce(search_name_count, 0) as count';
$sSQL .= ' FROM word WHERE word_token in (';
$sSQL .= join(',', $oDB->getDBQuotedList($aTokens)).')';
Debug::printSQL($sSQL);
$aDBWords = $oDB->getAll($sSQL, null, 'Could not get word tokens.');
foreach ($aDBWords as $aWord) {
$oToken = null;
$iId = (int) $aWord['word_id'];
if ($aWord['class']) {
// Special terms need to appear in their normalized form.
if ($aWord['word']) {
$sNormWord = $aWord['word'];
if ($oNormalizer != null) {
$sNormWord = $oNormalizer->transliterate($aWord['word']);
}
if (strpos($sNormQuery, $sNormWord) === false) {
continue;
}
}
if ($aWord['class'] == 'place' && $aWord['type'] == 'house') {
$oToken = new Token\HouseNumber($iId, trim($aWord['word_token']));
} elseif ($aWord['class'] == 'place' && $aWord['type'] == 'postcode') {
if ($aWord['word']
&& pg_escape_string($aWord['word']) == $aWord['word']
) {
$oToken = new Token\Postcode(
$iId,
$aWord['word'],
$aWord['country_code']
);
}
} else {
// near and in operator the same at the moment
$oToken = new Token\SpecialTerm(
$iId,
$aWord['class'],
$aWord['type'],
$aWord['operator'] ? Operator::NEAR : Operator::NONE
);
}
} elseif ($aWord['country_code']) {
// Filter country tokens that do not match restricted countries.
if (!$aCountryCodes
|| in_array($aWord['country_code'], $aCountryCodes)
) {
$oToken = new Token\Country($iId, $aWord['country_code']);
}
} else {
$oToken = new Token\Word(
$iId,
$aWord['word_token'][0] != ' ',
(int) $aWord['count'],
substr_count($aWord['word_token'], ' ')
);
}
if ($oToken) {
$this->addToken($aWord['word_token'], $oToken);
}
}
}
/**
* Add a new token for the given word.
*
* @param string $sWord Word the token describes.
* @param object $oToken Token object to add.
*
* @return void
*/
public function addToken($sWord, $oToken)
{
if (isset($this->aTokens[$sWord])) {
$this->aTokens[$sWord][] = $oToken;
} else {
$this->aTokens[$sWord] = array($oToken);
}
}
public function debugTokenByWordIdList()
{
$aWordsIDs = array();
foreach ($this->aTokens as $sToken => $aWords) {
foreach ($aWords as $aToken) {
if ($aToken->iId !== null) {
$aWordsIDs[$aToken->iId] =
'#'.$sToken.'('.$aToken->iId.')#';
}
}
}
return $aWordsIDs;
}
public function debugInfo()
{
return $this->aTokens;
}
}