Merge remote-tracking branch 'upstream/master'

classes/Endpoint.php

@@ -9,59 +9,88 @@ class Endpoint{
   	$this->params = $params;
   }
   
-   public function query($q, $output = 'json'){
-        global $conf;
-        $auxoutput = $this->params['output'];
-        $accept = 'application/sparql-results+json';
-        if($output != null){
-          $this->params['output'] = $output;
-        }
-        if($output == 'xml'){
-          $accept = 'application/sparql-results+xml';
-        }elseif($output == 'rdf'){
-          $accept = 'application/rdf+xml';
+  public function query($q, $output = 'json'){
+    global $conf;
+    $auxoutput = $this->params['output'];
+    $accept = 'application/sparql-results+json';
+    if($output != null){
+      $this->params['output'] = $output;
+    }
+    if($output == 'xml'){
+      $accept = 'application/sparql-results+xml';
+    }elseif($output == 'rdf'){
+      $accept = 'application/rdf+xml';
+    }
+    $aux = "";
+    $modified = 0;
+    $now = time();
+    $cacheFile = "";
+    if(is_int($conf['cache']['global']) && $conf['cache']['global'] > 0){
+      $cacheFile = $conf['home']."cache/query".md5($this->sparqlUrl.$q);
+      if(file_exists($cacheFile)){
+        $modified = filemtime($cacheFile);
+      }
+    }
+    if(is_int($conf['cache']['global']) && $conf['cache']['global'] > 0 && $modified + $conf['cache']['global'] > $now){
+     if($conf['debug']){
+       $msg = "Taking data from cache ($cacheFile). Renewal in ".($modified + $conf['cache']['global'] - $now)." seconds\n";
+       trigger_error($msg);
+       echo $msg;
+     }
+       $aux = (file_get_contents($cacheFile));
+    }else{
+      $c = curl_init();
+      $context = array();
+      $context[0] = 'Connection: close';
+      $context[1] = 'Accept: '.$accept;
+      $params = $this->params;
+      $params['query'] = $q;
+      $url = $this->sparqlUrl.'?'.http_build_query($params, '', '&');
+      curl_setopt($c, CURLOPT_URL, $url);
+      curl_setopt($c, CURLOPT_HTTPHEADER, $context);
+      curl_setopt($c, CURLOPT_USERAGENT, "LODSPeaKr version ".$conf['version']);
+      curl_setopt($c, CURLOPT_RETURNTRANSFER, true);
+      $aux = curl_exec($c); // execute the curl command 
+      if($conf['debug']){
+        if($aux == false){
+          trigger_error("Error executing SPARQL query (".$this->sparqlUrl."): ".curl_error($c), E_USER_ERROR);
+          echo("Error executing SPARQL query (".$this->sparqlUrl."): ".curl_error($c));
         }
-        $c = curl_init();
-        $context = array();
-        $context[0] = 'Connection: close';
-        $context[1] = 'Accept: '.$accept;
-        $params = $this->params;
-        $params['query'] = $q;
-        $url = $this->sparqlUrl.'?'.http_build_query($params, '', '&');
-        curl_setopt($c, CURLOPT_URL, $url);
-        curl_setopt($c, CURLOPT_HTTPHEADER, $context);
-        curl_setopt($c, CURLOPT_USERAGENT, "LODSPeaKr version ".$conf['version']);
-        curl_setopt($c, CURLOPT_RETURNTRANSFER, true);
-        $aux = curl_exec($c); // execute the curl command 
+      }
+      curl_close($c);
+      $this->params['output'] = $auxoutput;
+      if(is_int($conf['cache']['global']) && $conf['cache']['global'] > 0){
+        file_put_contents($cacheFile,($aux), LOCK_EX);
         if($conf['debug']){
-          if($aux == false){
-          	trigger_error("Error executing SPARQL query (".$this->sparqlUrl."): ".curl_error($c), E_USER_ERROR);
-          	echo("Error executing SPARQL query (".$this->sparqlUrl."): ".curl_error($c));
-          }
-        }
-        curl_close($c);
-        $this->params['output'] = $auxoutput;
-        if(preg_match("/select/i", $q)){
-          $r = json_decode($aux, true);
-          if($conf['debug']){
-          	if($r == false){
-          	  trigger_error("Warning: Results from a SELECT sparql query couldn't get parsed", E_USER_WARNING);
-          	  echo("Warning: Results from a SELECT sparql query couldn't get parsed");
-          	}
-          }
-          return $r;
-        }
-        if(preg_match("/describe/i", $q)){
-          return $aux;
+          $msg = "Notice: Writing results in ".$cacheFile."\n";
+          trigger_error($msg, E_USER_NOTICE);
+          echo($msg);
         }
-        if(preg_match("/construct/i", $q)){
-          return $aux;
-        }
-        if(preg_match("/ask/i", $q)){
-          $r = json_decode($aux, true);
-          return $r;
+      }
+    }
+    if(preg_match("/select/i", $q)){
+      $r = json_decode($aux, true);
+      if($conf['debug']){
+        if($r == false){
+          trigger_error("Warning: Results from a SELECT sparql query couldn't get parsed", E_USER_WARNING);
+          echo("Warning: Results from a SELECT sparql query couldn't get parsed");
         }
+      }
+      return $r;
+    }  
+    
+    
+    if(preg_match("/describe/i", $q)){
+      return $aux;
+    }
+    if(preg_match("/construct/i", $q)){
+      return $aux;
     }
+    if(preg_match("/ask/i", $q)){
+      $r = json_decode($aux, true);
+      return $r;
+    }
+  }
   
   public function queryPost($q){
   	$params =  $this->params;