- add ResumptionToken for OAI-ListIdentifiers

- max identifiers and reciords via config
- add constants.php
- add clear-expired command for deleting obsolete cache

app/Models/Oai/Configuration.php

@@ -0,0 +1,68 @@
+<?php
+
+namespace App\Models\Oai;
+
+class Configuration
+{
+    /**
+     * Hold path where to store temporary resumption token files.
+     *
+     * @var string
+     */
+    private $pathTokens = '';
+
+    /**
+     * Holds maximum number of identifiers to list per request.
+     *
+     * @var int
+     */
+    private $maxListIds = 15;
+
+    /**
+     * Holds maximum number of records to list per request.
+     *
+     * @var int
+     */
+    private $maxListRecs = 15;
+
+    public function __construct()
+    {
+        $this->maxListIds = config('oai.max.listidentifiers');
+
+        $this->maxListRecs = config('oai.max.listrecords');
+
+        $this->pathTokens = config('app.workspacePath')
+        . DIRECTORY_SEPARATOR .'tmp'
+        . DIRECTORY_SEPARATOR . 'resumption';
+    }
+
+    /**
+     * Return temporary path for resumption tokens.
+     *
+     * @return string Path.
+     */
+    public function getResumptionTokenPath()
+    {
+        return $this->pathTokens;
+    }
+
+    /**
+     * Return maximum number of listable identifiers per request.
+     *
+     * @return int Maximum number of listable identifiers per request.
+     */
+    public function getMaxListIdentifiers()
+    {
+        return $this->maxListIds;
+    }
+
+    /**
+     * Return maximum number of listable records per request.
+     *
+     * @return int Maximum number of listable records per request.
+     */
+    public function getMaxListRecords()
+    {
+        return $this->maxListRecs;
+    }
+}

app/Models/Oai/ResumptionToken.php

@@ -7,13 +7,12 @@ namespace App\Models\Oai;
  */
 class ResumptionToken
 {
-
-    /**
-     * Holds dataset ids
+     /**
+     * Holds dcoument ids
      *
      * @var array
      */
-    private $datasetIds = array();
+    private $documentIds = array();
 
     /**
      * Holds metadata prefix information
@@ -34,7 +33,7 @@ class ResumptionToken
      *
      * @var integer
      */
-    private $startPostition = 0;
+    private $startPosition = 0;
 
     /**
      * Holds total amount of document ids
@@ -50,7 +49,7 @@ class ResumptionToken
      */
     public function getDocumentIds()
     {
-        return $this->_documentIds;
+        return $this->documentIds;
     }
 
     /**
@@ -60,17 +59,17 @@ class ResumptionToken
      */
     public function getMetadataPrefix()
     {
-        return $this->_metadataPrefix;
+        return $this->metadataPrefix;
     }
 
      /**
      * Return setted resumption id after successful storing of resumption token.
      *
-     * @return string Returns resumption id
+     * @return string
      */
     public function getResumptionId()
     {
-        return $this->_resumptionId;
+        return $this->resumptionId;
     }
 
     /**
@@ -80,7 +79,7 @@ class ResumptionToken
      */
     public function getStartPosition()
     {
-        return $this->_startPosition;
+        return $this->startPosition;
     }
 
     /**
@@ -90,7 +89,7 @@ class ResumptionToken
      */
     public function getTotalIds()
     {
-        return $this->_totalIds;
+        return $this->totalIds;
     }
 
     /**
@@ -105,7 +104,7 @@ class ResumptionToken
             $idsToStore = array($idsToStore);
         }
 
-        $this->_documentIds = $idsToStore;
+        $this->documentIds = $idsToStore;
     }
 
     /**
@@ -116,7 +115,7 @@ class ResumptionToken
      */
     public function setMetadataPrefix($prefix)
     {
-        $this->_metadataPrefix = $prefix;
+        $this->metadataPrefix = $prefix;
     }
 
     /**
@@ -126,7 +125,7 @@ class ResumptionToken
      */
     public function setResumptionId($resumptionId)
     {
-        $this->_resumptionId = $resumptionId;
+        $this->resumptionId = $resumptionId;
     }
 
     /**
@@ -137,7 +136,7 @@ class ResumptionToken
      */
     public function setStartPosition($startPosition)
     {
-        $this->_startPosition = (int) $startPosition;
+        $this->startPosition = (int) $startPosition;
     }
 
     /**
@@ -147,6 +146,6 @@ class ResumptionToken
      */
     public function setTotalIds($totalIds)
     {
-        $this->_totalIds = (int) $totalIds;
+        $this->totalIds = (int) $totalIds;
     }
 }

app/Models/Oai/ResumptionTokenException.php

@@ -0,0 +1,8 @@
+<?php
+namespace App\Models\Oai;
+
+use Exception;
+
+class ResumptionTokenException extends Exception
+{
+}

app/Models/Oai/ResumptionTokens.php

@@ -0,0 +1,148 @@
+<?php
+
+namespace App\Models\Oai;
+
+use App\Models\Oai\ResumptionToken;
+use App\Models\Oai\ResumptionTokenException;
+use Illuminate\Support\Facades\Cache;
+
+/**
+ * Handling (read, write) of resumption tokens
+ */
+class ResumptionTokens
+{
+    /**
+     * Holds resumption path without trailing slash.
+     *
+     * @var string
+     */
+    private $resumptionPath = null;
+
+    private $resumptionId = null;
+    protected $filePrefix = 'rs_';
+    protected $fileExtension = 'txt';
+
+    /**
+     * Constructor of class
+     *
+     * @param $resPath (Optional) Initialise resumption path on create.
+     *
+     */
+    public function __construct($resPath = null)
+    {
+        if (false === empty($resPath)) {
+            $this->setResumptionPath($resPath);
+        }
+    }
+
+    /**
+     * Generate a unique file name and resumption id for storing resumption token.
+     * Double action because file name 8without prefix and file extension)
+     * and resumption id should be equal.
+     *
+     * @return filename Generated filename including path and file extension.
+     */
+    private function generateResumptionName()
+    {
+        $fc = 0;
+
+        // generate a unique partial name
+        // return value of time() should be enough
+        $uniqueId = time();
+
+        $fileExtension = $this->fileExtension;
+        if (false === empty($fileExtension)) {
+            $fileExtension = '.' . $fileExtension;
+        }
+
+        do {
+            $uniqueName = sprintf('%s%05d', $uniqueId, $fc++);
+            $file = $this->resumptionPath . DIRECTORY_SEPARATOR . $this->filePrefix . $uniqueName . $fileExtension;
+        } while (true === file_exists($file));
+
+        $this->resumptionId = $uniqueName;
+        return $uniqueName;
+        //return $file;
+    }
+
+    public function getResumptionToken($resId)
+    {
+
+        $token = null;
+
+        // $fileName = $this->resumptionPath . DIRECTORY_SEPARATOR . $this->filePrefix . $resId;
+        // if (false === empty($this->fileExtension)) {
+        //     $fileName .= '.' . $this->fileExtension;
+        // }
+
+        // if (true === file_exists($fileName)) {
+        if (Cache::has($resId)) {
+            //$fileContents = file_get_contents($fileName);
+            $fileContents = Cache::get($resId);
+
+            // if data is not unserializueabke an E_NOTICE will be triggerd and false returned
+            // avoid this E_NOTICE
+            $token = @unserialize($fileContents);
+            if (false === ($token instanceof ResumptionToken)) {
+                $token = null;
+            }
+        }
+        return $token;
+    }
+
+    /**
+     * Set resumption path where the resumption token files are stored.
+     *
+     * @throws Oai_Model_ResumptionTokenException Thrown if directory operations failed.
+     * @return void
+     */
+    public function setResumptionPath($resPath)
+    {
+        // expanding all symbolic links and resolving references
+        $realPath = realpath($resPath);
+
+        // if (empty($realPath) or false === is_dir($realPath)) {
+        //     throw new Oai_Model_ResumptionTokenException(
+        //         'Given resumption path "' . $resPath . '" (real path: "' . $realPath . '") is not a directory.'
+        //     );
+        // }
+
+        // if (false === is_writable($realPath)) {
+        //     throw new Oai_Model_ResumptionTokenException(
+        //         'Given resumption path "' . $resPath . '" (real path: "' . $realPath . '") is not writeable.'
+        //     );
+        // }
+        $this->resumptionPath = $realPath;
+    }
+
+     /**
+     * Store a resumption token
+     *
+     * @param Oai_Model_Resumptiontoken $token Token to store.
+     * @throws Oai_Model_ResumptionTokenException Thrown on file operation error.
+     * @return void
+     */
+    public function storeResumptionToken(ResumptionToken $token)
+    {
+
+        // $fileName = $this->generateResumptionName();
+        $uniqueName = $this->generateResumptionName();
+       
+
+        // $file = fopen($fileName, 'w+');
+        // if (false === $file) {
+        //     throw new ResumptionTokenException('Could not open file "' . $fileName . '" for writing!');
+        // }
+
+        $serialToken = serialize($token);
+        // if (false === fwrite($file, $serialToken)) {
+        //     throw new ResumptionTokenException('Could not write file "' . $fileName . '"!');
+        // }
+        // if (false === fclose($file)) {
+        //     throw new ResumptionTokenException('Could not close file "' . $fileName . '"!');
+        // }
+        Cache::put($uniqueName, $serialToken, now()->addMinutes(60));
+
+        $token->setResumptionId($this->resumptionId);
+    }
+}