<?php
/*
* This file is part of the WikiTagBundle package.
*
* (c) IRI <http://www.iri.centrepompidou.fr/>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace IRI\Bundle\WikiTagBundle\Utils;
use IRI\Bundle\WikiTagBundle\Entity\Tag;
class WikiTagUtils
{
// Constants
private static $WIKIPEDIA_API_URL = "http://fr.wikipedia.org/w/api.php";
private static $WIKIPEDIA_VERSION_PERMALINK_TEMPLATE = "http://fr.wikipedia.org/w/index.php?oldid=%s";
private static $DBPEDIA_URI_TEMPLATE = "http://dbpedia.org/resource/%s";
/**
* Cleans the tag label
*/
public static function normalizeTag($tag_label)
{
if(strlen($tag_label)==0){
return $tag_label;
}
$tag_label = trim($tag_label);//tag.strip()
$tag_label = str_replace("_", " ", $tag_label);//tag.replace("_", " ")
$tag_label = preg_replace('/\s+/u', ' ', $tag_label);//" ".join(tag.split())
$tag_label = ucfirst($tag_label);//tag[0].upper() + tag[1:]
return $tag_label;
}
/**
* Query wikipedia with a normalized label or a pageid
* return an array with the form
* array(
* 'new_label'=>$new_label,
* 'alternative_label'=>$alternative_label,
* 'status'=>$status,
* 'wikipedia_url'=>$url,
* 'wikipedia_alternative_url'=>$alternative_url,
* 'pageid'=>$pageid,
* 'alternative_pageid'=>$alternative_pageid,
* 'dbpedia_uri'=>$dbpedia_uri,
* 'revision_id'=> ,
* 'response'=> the original wikipedia json response
* )
*
* @param string $tag_label_normalized
* @param bigint $page_id
* @return array
*/
public static function getWikipediaInfo($tag_label_normalized, $page_id=null, $ignore_wikipedia_error=false, $logger = null)
{
$params = array('action'=>'query', 'prop'=>'info|categories|langlinks', 'inprop'=>'url', 'lllimit'=>'500', 'cllimit'=>'500', 'rvprop'=>'ids', 'format'=>'json');
if($tag_label_normalized!=null){
$params['titles'] = urlencode($tag_label_normalized);
}
else if($page_id!=null){
$params['pageids'] = $page_id;
}
else{
return WikiTagUtils::returnNullResult(null);
}
try {
$ar = WikiTagUtils::requestWikipedia($params);
}
catch(\Exception $e) {
if($ignore_wikipedia_error) {
if(!is_null($logger)) {
$logger->err("Error when querying wikipedia : ".$e->getMessage()." with trace : ".$e->getTraceAsString());
}
return WikiTagUtils::returnNullResult(null);
}
else {
throw $e;
}
}
$res = $ar[0];
$original_response = $res;
$pages = $ar[1];
// If there 0 or more than 1 result, the query has failed
if(count($pages)>1 || count($pages)==0){
return WikiTagUtils::returnNullResult($res);
}
// get first result
$page = reset($pages);
// Unknow entry ?
if(array_key_exists('missing', $page) || array_key_exists('invalid', $page)){
return WikiTagUtils::returnNullResult($res);
}
// The entry exists, we get the datas.
$url = array_key_exists('fullurl', $page) ? $page['fullurl'] : null;
$pageid = array_key_exists('pageid', $page) ? $page['pageid'] : null;
$new_label = array_key_exists('title', $page) ? $page['title'] : null;
// We test the status (redirect first because a redirect has no categories key)
if(array_key_exists('redirect', $page)){
//return " REDIRECT";
$status = Tag::$TAG_URL_STATUS_DICT["redirection"];
}
else if(WikiTagUtils::isHomonymy($page)){
//return " HOMONYMY";
$status = Tag::$TAG_URL_STATUS_DICT["homonyme"];
}
else{
//return " MATCH";
$status = Tag::$TAG_URL_STATUS_DICT["match"];
}
// In redirection, we have to get more datas by adding redirects=true to the params
$alternative_label = null;
$alternative_url = null;
$alternative_pageid = null;
if($status==Tag::$TAG_URL_STATUS_DICT["redirection"])
{
$params['redirects'] = "true";
try {
$ar = WikiTagUtils::requestWikipedia($params);
}
catch(\Exception $e) {
if($ignore_wikipedia_error) {
if(!is_null($logger)) {
$logger->error("Error when querying wikipedia for redirection : ".$e->getMessage()." with trace : ".$e->getTraceAsString());
}
return WikiTagUtils::returnNullResult(null);
}
else {
throw $e;
}
}
$res = $ar[0];
$pages = $ar[1];
#we know that we have at least one answer
if(count($pages)>1 || count($pages)==0){
return WikiTagUtils::returnNullResult($res);
}
// get first result
$page = reset($pages);
$alternative_label = array_key_exists('title', $page) ? $page['title'] : null;
$alternative_url = array_key_exists('fullurl', $page) ? $page['fullurl'] : null;
$alternative_pageid = array_key_exists('pageid', $page) ? $page['pageid'] : null;
}
$revision_id = $page['lastrevid'];
// process language to extract the english label
$english_label = null;
if($status==Tag::$TAG_URL_STATUS_DICT["match"] || $status==Tag::$TAG_URL_STATUS_DICT["redirection"]){
if(array_key_exists("langlinks", $page)){
foreach ($page["langlinks"] as $ar) {
if($ar["lang"]=="en"){
$english_label = $ar["*"];
break;
}
}
}
}
// We create the dbpedia uri.
$dbpedia_uri = null;
if($english_label!=null && strpos($english_label, '#')===false){
$dbpedia_uri = WikiTagUtils::getDbpediaUri($english_label);
}
$wp_response = array(
'new_label'=>$new_label,
'alternative_label'=>$alternative_label,
'status'=>$status,
'wikipedia_url'=>$url,
'wikipedia_alternative_url'=>$alternative_url,
'pageid'=>$pageid,
'alternative_pageid'=>$alternative_pageid,
'dbpedia_uri'=>$dbpedia_uri,
'revision_id'=>$revision_id,
'response'=>$original_response);
return $wp_response;
}
/**
* build and do the request to Wikipedia.
*
* @param array $params
* @return array
*/
private static function requestWikipedia($params)
{
$params_str = '';
foreach ($params as $key => $value) {
if ($params_str==''){
$params_str = $key.'='.$value;
}
else{
$params_str .= '&'.$key.'='.$value;
}
}
$url = WikiTagUtils::$WIKIPEDIA_API_URL.'?'.$params_str;
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $url);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
//TODO: change
curl_setopt($ch, CURLOPT_USERAGENT, 'http://www.iri.centrepompidou.fr');
curl_setopt($ch, CURLOPT_TIMEOUT_MS, 5000);
$res = curl_exec($ch);
$curl_errno = curl_errno($ch);
$curl_error = curl_error($ch);
curl_close($ch);
if ($curl_errno > 0) {
throw new \Exception("Wikipedia request failed. cURLError #$curl_errno: $curl_error\n", $curl_errno, null);
}
$val = json_decode($res, true);
$pages = $val["query"]["pages"];
return array($res, $pages);
}
/**
* Returns tag with a null result, usually used after a failed request on Wikipedia
*/
private static function returnNullResult($response)
{
return array('new_label'=>null, 'status'=>Tag::$TAG_URL_STATUS_DICT['null_result'], 'wikipedia_url'=>null, 'pageid'=>null, 'dbpedia_uri'=>null, 'revision_id'=>null, 'response'=>$response);
}
/**
* Returns tag with a null result, usually used after a failed request on Wikipedia
*/
private static function isHomonymy($page)
{
//$s = "";
foreach ($page["categories"] as $ar) {
//$s .= ", b : ".$ar." - title = ".$ar["title"].", strpos = ".strpos($ar["title"], 'Catégorie:Homonymie');
// Strict test because false can be seen as "O".
if(strpos($ar["title"], 'Catégorie:Homonymie')!==false || strpos($ar["title"], 'Category:Disambiguation')!==false){
//$s .= "TRUE";
return true;
}
}
return false;
}
/**
* Builds DbPedia URI
*/
private static function getDbpediaUri($english_label)
{
return sprintf(WikiTagUtils::$DBPEDIA_URI_TEMPLATE, WikiTagUtils::urlize_for_wikipedia($english_label));
}
/**
* URLencode label for wikipedia
*/
private static function urlize_for_wikipedia($label){
return urlencode(str_replace(" ", "_", $label));
}
}