upei_roblib_search/targets/eds/includes/rest/EBSCOAPI.php

<?php


/**
 * EBSCO API class
 *
 * PHP version 5
 *
 */


/**
 * EBSCO API class
 */
class EBSCOAPI
{
    /**
     * The authentication token used for API transactions
     * @global string
     */
    private $authenticationToken;


    /**
     * The session token for API transactions
     * @global string
     */
    private $sessionToken;

    /**
     * The EBSCOConnector object used for API transactions
     * @global object EBSCOConnector
     */
    private $connector;
    
    private $config;
    
    public function __construct($config) {
      $this->config = $config;
      $this->connector = new EBSCOConnector($config);
    }

    /**
     * Create a new EBSCOConnector object or reuse an existing one
     *
     * @param none
     *
     * @return EBSCOConnector object
     * @access public
     */
    public function connector($config)
    {
        if (empty($this->connector)) {
            $this->connector = new EBSCOConnector($config);
        }

        return $this->connector;
    }


    /**
     * Create a new EBSCOResponse object
     *
     * @param object $response
     *
     * @return EBSCOResponse object
     * @access public
     */
    public function response($response)
    {
        $responseObj = new EBSCOResponse($response);
        return $responseObj;
    }


    /**
     * Request authentication and session tokens, then send the API request.
     * Retry the request if authentication errors occur
     *
     * @param string  $action     The EBSCOConnector method name
     * @param array   $params     The parameters for the HTTP request
     * @param integer $attempts   The number of retries. The default number is 3 but can be increased.
     * 3 retries can handle a situation when both autentication and session tokens need to be refreshed + the current API call
     *
     * @return array              An associative array with results.
     * @access protected
     */
    protected function request($action, $params = null, $attempts = 3)
    {
        try {
            
            $authenticationToken = $this->getAuthToken();
            $sessionToken = $this->getSessionToken($authenticationToken);
            
            if(empty($authenticationToken)){
               $authenticationToken = $this -> getAuthToken();
            }
           
            if(empty($sessionToken)){
                $sessionToken = $this -> getSessionToken($authenticationToken,'y');
            }
                   
            $headers = array(
                'x-authenticationToken: ' . $authenticationToken,
                'x-sessionToken: ' . $sessionToken
            );

            $response = call_user_func_array(array($this->connector($this->config), "request{$action}"), array($params, $headers));
            $result = $this->response($response)->result();
            $results = $result;             
            return $results;
        } catch(EBSCOException $e) {
            try {
                // Retry the request if there were authentication errors
                $code = $e->getCode();
                switch ($code) {
                    case EBSCOConnector::EDS_AUTH_TOKEN_INVALID:
                        $authenticationToken = $this->getAuthToken();                
                        $sessionToken = $this ->getSessionToken($authenticationToken);
                        $headers = array(
                'x-authenticationToken: ' . $authenticationToken,
                'x-sessionToken: ' . $sessionToken
            );
                        if ($attempts > 0) {
                            return $this->request($action, $params, $headers, --$attempts);
                        }
                        break;
                    case EBSCOConnector::EDS_SESSION_TOKEN_INVALID:
                        $sessionToken = $this ->getSessionToken($authenticationToken,'y');
                        $headers = array(
                'x-authenticationToken: ' . $authenticationToken,
                'x-sessionToken: ' . $sessionToken
            );
                        if ($attempts > 0) {
                            return $this->request($action, $params, $headers, --$attempts);
                        }
                        break;
                    default:
                        $result = array(
                            'error' => $e->getMessage()
                        );
                        return $result;
                        break;
                }
            }  catch(Exception $e) {
                $result = array(
                    'error' => $e->getMessage()
                );
                return $result;
            }
        } catch(Exception $e) {
            $result = array(
                'error' => $e->getMessage()
            );
            return $result;
        }
    }
    
    private function writeLockFile(){
       $tokenFile = fopen("edstoken.txt","w+");
                $result = $this->apiAuthenticationToken();
                fwrite($tokenFile, $result['authenticationToken']."\n");
                fwrite($tokenFile, $result['authenticationTimeout']."\n");
                fwrite($tokenFile, $result['authenticationTimeStamp']);
                fclose($tokenFile);
                return $result['authenticationToken'];
    }
    
    /*
     * Get authentication token from appication scop 
     * Check authToen's expiration 
     * if expired get a new authToken and re-new the time stamp
     * 
     * @param none
     * 
     * @access public
     */
    public function getAuthToken(){
        $lockFile = fopen("edslock.txt","r");
        $tokenFile =fopen("edstoken.txt","r");
        if(empty($lockFile) || empty($tokenFile)){
          return $this->writeLockFile();
        }
        while(!feof($tokenFile)){
            $authToken = rtrim(fgets($tokenFile),"\n");
            $timeout = fgets($tokenFile)-600;
            $timestamp = fgets($tokenFile);
        }
        fclose($tokenFile);
        if(time()-$timestamp>=$timeout){
            // Lock check.
            if(flock($lockFile, LOCK_EX)){
                $tokenFile = fopen("edstoken.txt","w+");
                $result = $this->apiAuthenticationToken();
                fwrite($tokenFile, $result['authenticationToken']."\n");
                fwrite($tokenFile, $result['authenticationTimeout']."\n");
                fwrite($tokenFile, $result['authenticationTimeStamp']);
                fclose($tokenFile);
                return $result['authenticationToken'];
            }else{
                return $authToken;
            }
        }else{
            return $authToken;
        }
        fclose($lockFile);       
    }
    
    /**
     * Wrapper for authentication API call
     *
     * @param none
     *
     * @access public
     */
    public function apiAuthenticationToken()
    {
        $response = $this->connector->requestAuthenticationToken();
        $result = $this->response($response)->result();
        return $result;
    }

    /**
     * Get session token for a profile 
     * If session token is not available 
     * a new session token will be generated
     * 
     * @param Authentication token, Profile 
     * @access public
     */
    public function getSessionToken($authenToken, $invalid='n'){
        $token = ''; 
        
        // Check user's login status
        if(isset($_COOKIE['login'])){              
               if($invalid=='y'){                   
                   $profile = $_SESSION['sessionToken']['profile'];
                   $sessionToken = $this->apiSessionToken($authenToken, $profile,'n');                  
                   $_SESSION['sessionToken']=$sessionToken;                 
               }
               $token = $_SESSION['sessionToken']['sessionToken'];            
        }
        else if(isset($_COOKIE['Guest'])){
               if($invalid=='y'){                   
                   $profile = $_SESSION['sessionToken']['profile'];
                   $sessionToken = $this->apiSessionToken($authenToken, $profile,'y');   
                   $_SESSION['sessionToken']=$sessionToken;
               }     
               $token = $_SESSION['sessionToken']['sessionToken'];   
        }else{            
            //$xml ="Config.xml";
            //$dom = new DOMDocument();
            //$dom->load($xml); 
            //$EDSCredentials = $dom ->getElementsByTagName('EDSCredentials')->item(0);
            //$users = $EDSCredentials -> getElementsByTagName('User');
            $profileId = $this->config['profile'];
            //foreach($users as $user){
            //   $userType = $user->getElementsByTagName('ClientUser')->item(0)->nodeValue;
             //   if($userType == 'guest'){                     
             //   $profileId = $user -> getElementsByTagName('EDSProfile')->item(0)->nodeValue;               
            //    break;
             //   }
            //}                     
            $sessionToken = $this->apiSessionToken($authenToken, $profileId,'y');
            $_SESSION['profile'] = $profileId;   
            $_SESSION['sessionToken']=$sessionToken;          
            setcookie("Guest", $profileId, 0);
            $token = $sessionToken['sessionToken'];           
        }     
        return $token;
    }

    /**
     * Wrapper for session API call
     *
     * @param Authentication token
     *
     * @access public
     */
    public function apiSessionToken($authenToken, $profile, $guest)
    {
        // Add authentication tokens to headers
        $headers = array(
            'x-authenticationToken: ' . $authenToken
        );

        $response = $this->connector($this->config)->requestSessionToken($headers, $profile,$guest);
        $result = $this->response($response)->result();
        $token = array(
            'sessionToken'=>$result,
            'profile' => $profile
        );   
         return $token;
    }
   
    /**
     * Wrapper for end session API call
     *
     * @param Authentication token
     *
     * @access public
     */
    public function apiEndSessionToken($authenToken, $sessionToken){
        
        // Add authentication tokens to headers
        $headers = array(
            'x-authenticationToken: '.$authenToken
        );
        
        $this -> connector($this->config)->requestEndSessionToken($headers, $sessionToken);
    }

    /**
     * Wrapper for search API call
     *
     * @param 
     *
     * @throws object             PEAR Error
     * @return array              An array of query results
     * @access public
     */
    public function apiSearch($params) {
        
        $results = $this->request('Search', $params);
        return $results;
    }


    /**
     * Wrapper for retrieve API call
     *
     * @param array  $an          The accession number
     * @param string $start       The short database name
     *
     * @throws object             PEAR Error
     * @return array              An associative array of data
     * @access public
     */
    public function apiRetrieve($an, $db, $term)
    {
        // Add the HTTP query params
        $params = array(
            'an'        => $an,
            'dbid'      => $db,
            'highlightterms' => $term // Get currect param name
        );
        $params = http_build_query($params);
        $result = $this->request('Retrieve', $params);
        return $result;
    }


    /**
     * Wrapper for info API call
     *
     * @return array              An associative array of data
     * @access public
     */
    public function getInfo()
    {
        if(isset($_SESSION['info'])){
            $InfoArray = $_SESSION['info'];
            $timestamp = $InfoArray['timestamp'];
            if(time()-$timestamp>=3600){        
                // Get new Info for the profile
                $InfoArray = $this->apiInfo();
                $_SESSION['info'] = $InfoArray;
                $info = $InfoArray['Info'];           
            }else{
                $info = $InfoArray['Info'];
            }
        }else{              
            // Get new Info for the profile
            $InfoArray = $this->apiInfo();
            $_SESSION['info'] = $InfoArray;
            $info = $InfoArray['Info'];          
        }
        return $info;
    }
    
    public function apiInfo(){
        
        $response = $this->request('Info','');
        $Info = array(
            'Info' => $response,
            'timestamp'=>time()
        ); 
        return $Info;
    }
}
?>