OnApp.php

<?php
/**
 * Current OnApp PHP API wrapper version
 */
define( 'ONAPP_VERSION', '2.0' );

/**
 * The OnApp class uses this variable to define the Proxy server used by cURL
 */
define( 'ONAPP_OPTION_CURL_PROXY', 'proxy' );

/**
 * The OnApp class uses this variable to define the URL to the API used by cURL
 */
define( 'ONAPP_OPTION_CURL_URL', 'url' );

/**
 * The OnApp class uses this variable to define the data type which would help transfer data between the client and the API server
 *
 * Possible values:
 *	 - xml	(default)
 *	 - json (will be available after the parcer is created)
 */
define( 'ONAPP_OPTION_API_TYPE', 'data_type' );

/**
 * The OnApp class uses this variable to define the charsets used to transfer data between the client and the API server
 *
 * Possible values:
 *	 - charset=utf-8 (default)
 */
define( 'ONAPP_OPTION_API_CHARSET', 'charset' );

/**
 * The OnApp class uses this value to define the content type used to transfer data between the client and the API server
 *
 * Possible values:
 *	 - application/xml (default)
 *	 - application/json (will be available after the Json parcer is created)
 */
define( 'ONAPP_OPTION_API_CONTENT', 'content' );

/**
 * TODO add description
 */
define( 'ONAPP_OPTION_DEBUG_MODE', 'debug_mode' );

/**
 * The OnApp class uses this field name to map this field in the API response and variable in the class
 * The field name is used to unserialize the API server response to the necessary class.
 */
define( 'ONAPP_FIELD_MAP', 'map' );

/**
 * The field name that stands for the mapped field type in the API response
 *
 * The field is used to unserialize the object into API request.
 * Possible values:
 *	 - integer
 *	 - ...
 */
define( 'ONAPP_FIELD_TYPE', 'type' );

/**
 * The field name that stands for the field access in the API response
 *
 * Used to unserialize the object into API request.
 * Possible values:
 *	 - true
 *	 - false
 */
define( 'ONAPP_FIELD_READ_ONLY', 'read_only' );

/**
 * The flag to exclude this field from sending request
 *
 * Possible values:
 *	 - true
 *	 - false
 */
define( 'ONAPP_FIELD_SKIP_FROM_REQUEST', 'skip' );

/**
 * The field name that specifies if it is necessary to be used in the API request when new objects are created or existing edited
 *
 * Possible values:
 *	 - true
 *	 - false
 */
define( 'ONAPP_FIELD_REQUIRED', 'required' );

/**
 * The field name that stands for the default field value
 *
 * The field name is used to unserialize if the field was changed or not loaded.
 */
define( 'ONAPP_FIELD_DEFAULT_VALUE', 'default' );

/**
 * Specify field type to serialize and unserialize obgect using their name
 */
define( 'ONAPP_FIELD_CLASS', 'class' );

/**
 *
 */
define( 'ONAPP_GETRESOURCE_DEFAULT', 'default' );

/**
 *
 */
define( 'ONAPP_GETRESOURCE_LOAD', 'load' );

/**
 *
 */
define( 'ONAPP_GETRESOURCE_LIST', 'list' );

/**
 *
 *
 */
define( 'ONAPP_GETRESOURCE_ADD', 'add' );

/**
 *
 *
 */
define( 'ONAPP_GETRESOURCE_EDIT', 'edit' );

/**
 *
 *
 */
define( 'ONAPP_GETRESOURCE_DELETE', 'delete' );

/**
 *
 *
 */
define( 'ONAPP_GETRESOURCE_VERSION', 'version' );

/**
 *
 *
 */
define( 'ONAPP_ACTIVATE_GETLIST', 'getList' );

/**
 *
 *
 */
define( 'ONAPP_ACTIVATE_LOAD', 'load' );

/**
 *
 *
 */
define( 'ONAPP_ACTIVATE_SAVE', 'save' );

/**
 *
 *
 */
define( 'ONAPP_ACTIVATE_DELETE', 'delete' );

/**
 * Specify the GET request
 *
 */
define( 'ONAPP_REQUEST_METHOD_GET', 'GET' );

/**
 * Specify the POST request
 *
 */
define( 'ONAPP_REQUEST_METHOD_POST', 'POST' );

/**
 * Specify the PUT request
 *
 */
define( 'ONAPP_REQUEST_METHOD_PUT', 'PUT' );

/**
 * Specify the DELETE request
 *
 */
define( 'ONAPP_REQUEST_METHOD_DELETE', 'DELETE' );

/**
 * API Wrapper for OnApp
 *
 *
 * @package OnApp
 *
 *
 * @todo	Pack using the lib (http://pecl.php.net/)
 *
 * The wrapper is used to describe the following basic methods: {@link load},
 * {@link save}, {@link delete} and {@link getList}.
 *
 * To create a new class inheriting this one, re-define the
 * following variables:
 * <code>
 *
 *	  // root tag used in the API request
 *	  var $_tagRoot	 = '<root>';
 *
 *	  // alias processing the object data
 *	  var $_resource = '<alias>';
 *
 *	  // the fields array used in the response and request to the API server
 *	  var $fields	= array(
 *	   ...
 *	  )
 * </code>
 *
 * To create a read-only class, close the save and delete methods.
 * To re-define the traditional API aliases to the non-traditional,
 * re-define the  {@link getResource},	{@link getResourceADD}, {@link getResourceEDIT},
 * {@link getResourceLOAD},	 {@link getResourceDELETE} and	{@link getResourceLIST}
 * methods in the class that will be inheriting the ONAPP class.
 *
 *
 * This API provides an interface to onapp.net allowing common virtual machine
 * and account management tasks
 *
 * <b> Usage OnApp_VirtualMachine class example ( Could be applied almost to any of the Wrapper classes ): </b> <br /><br />
 * <b> Important ( OnApp CP Permissions Set Up): </b>
 * <code>
 *	   Go to OnApp CP.
 *	   Users and Groups -> Roles
 *	   Push pencil edit icon to edit role of the user which you are going to use.
 *	   Check checkbox { View OnApp version (settings.version) }
 *	   Check other permissions in order to perform particular actions.
 *</code>
 *
 * <b>Code example:</b> <br />
 *
 * Require Wrapper AutoLoad Class:
 *
 * <code>
 *	  require_once '{Path to the Wrapper}/OnAppInit.php';
 * </code>
 *
 *
 * Get OnApp Instance:
 *
 * <code>
 *	   $onapp = new OnApp_Factory('{IP Address / Hostname}', '{Username}', '{Password}');
 * </code>
 *
 *
 * Get OnApp_VirtualMachine Instance:
 *
 * <code>
 *	   $vm_obj = $onapp->factory('VirtualMachine', {debug mode boolean, not required} );
 * </code>
 *
 *
 * Get the list of VMs:
 *
 * <code>
 *	   $vms	   = $vm_obj->getList();
 * </code>
 *
 *
 * Get particular VM:
 *
 * <code>
 *	   $vm	   = $vm_obj->load({VM ID});
 * </code>
 *
 *
 * Create a VM:
 *
 * <code>
 *	   $vm_obj->_label				 = '{VM Label}';
 *	   $vm_obj->_memory				 = {VM RAM };
 *	   $vm_obj->_cpu_shares			 = {VM CPU priority};
 *	   $vm_obj->_hostname			 = '{Hostname}';
 *	   $vm_obj->_cpus				 = {number of VM CPUs};
 *	   $vm_obj->_primary_disk_size	 = {VM Disk Space};
 *	   $vm_obj->_swap_disk_size		 = {VM Swap Size};
 *	   $vm_obj->_template_id		 = {VM Template ID};
 *	   $vm_obj->_allowed_hot_migrate = {VM Hot Migrate Boolean Value};
 *
 *	   $vm_obj->save();
 * </code>
 *
 *
 * Edit VM:
 *
 * <code>
 *	   $vm_obj->_id = {VM ID};
 *	   $vm_obj->_{Field You Want To Edit} = {New Value};
 *
 *	   $vm_obj->save();
 * </code>
 *
 *
 * Getting debug log ( depends on debug mode ):
 *
 * <code>
 *	   print_r( $vm_obj );
 * </code>
 *
 * For full fields reference and curl request details visit: ( http://help.onapp.com/manual.php?m=2 )
 */
class OnApp {
	/**
	 * The list of all available options used in the class to create API requests and receive responses,
	 * as well as to serialize and unserialize.
	 *
	 * @access private
	 * @var	   array
	 */
	var $_knownOptions = array(
		ONAPP_OPTION_CURL_PROXY,
		ONAPP_OPTION_CURL_URL,
		ONAPP_OPTION_API_TYPE,
		ONAPP_OPTION_API_CHARSET,
		ONAPP_OPTION_API_CONTENT,
		ONAPP_OPTION_DEBUG_MODE
	);
	/**
	 * Default options used in the class to create API requests and receive responses,
	 * as well as serialize and unserialize objects.
	 *
	 * @access private
	 * @var	   array
	 */
	private $defaultOptions = array(
		// cURL proxy
		ONAPP_OPTION_CURL_PROXY	 => '',
		// cURL url
		ONAPP_OPTION_CURL_URL	 => '',
		// API request and response charset
		ONAPP_OPTION_API_CHARSET => 'charset=utf-8',
		// API request and response type
		ONAPP_OPTION_API_TYPE	 => 'json',
		// API request and response content
		ONAPP_OPTION_API_CONTENT => 'application/json',
		// Debug mode
		ONAPP_OPTION_DEBUG_MODE	 => false,
	);
	/**
	 * The array of the options used to create API requests and receive responses,
	 * as well as serialize and unserialize objects in the class
	 *
	 * By default equals to $_defaultOptions
	 *
	 * <code>
	 *	  var $options = array(
	 *
	 *		  // cURL proxy
	 *		  ONAPP_OPTION_CURL_PROXY	  => '',
	 *
	 *		  // cURL url
	 *		  ONAPP_OPTION_CURL_URL		  => '',
	 *
	 *		  // API request and response type
	 *		  ONAPP_OPTION_API_TYPE		  => 'xml',
	 *
	 *		  // API request and response charset
	 *		  ONAPP_OPTION_API_CHARSET	 => 'charset=utf-8',
	 *
	 *		  // API request and response content
	 *		  ONAPP_OPTION_API_CONTENT	 => 'application/xml',
	 *
	 *			// Debug mode
	 *			ONAPP_OPTION_DEBUG_MODE => false
	 *	  );
	 * </code>
	 *
	 * @access public
	 * @var	   array
	 */
	var $options = array();
	/**
	 * Object cURL
	 * PHP supports libcurl, a library created by Daniel Stenberg,
	 * that allows you to connect and communicate to many different types of servers with many different types of protocols.
	 * libcurl currently supports the http, https, ftp, gopher, telnet, dict, file and ldap protocols.
	 * libcurl also supports HTTPS certificates, HTTP POST, HTTP PUT, FTP uploading (this can also be done with PHP's ftp extension),
	 * HTTP form based upload, proxies, cookies and user+password authentication.
	 *
	 * @access private
	 * @var	   cURL
	 */
	var $_ch;
	/**
	 * Variable storing the data loaded by the API request. The data is static and cannot be changed by the class setters
	 *
	 * @access private
	 * @var	   object
	 */
	var $_obj;
	/**
	 * cURL Object alias used as the basic alias to the load, save, delete and getList methods
	 *
	 * @access private
	 * @var	   string
	 */
	var $_resource = null;
	/**
	 * @access private
	 * @var	   string
	 */
	var $_tagRoot = null;
	/**
	 * @access private
	 * @var	   array
	 */
	var $_tagRequired = null;
	/**
	 * @access private
	 * @var	   boolean
	 * @todo   move in to getter an setter
	 */
	var $_is_auth = false;
	/**
	 * @access private
	 * @var	   boolean
	 * @todo   move in to getter an setter
	 */
	var $_is_changed = false;
	/**
	 * @access private
	 * @var	   boolean
	 * @todo   move in to getter an setter
	 */
	var $_is_deleted = false;
	/**
	 * Return OnApp version
	 *
	 * @access private
	 * @var	   sting
	 */
	protected $version;
	/**
	 * Return OnApp release
	 *
	 * @access private
	 * @var		  sting
	 */
	var $_release;
	/**
	 * Return OnApp fields array mapping
	 *
	 * @access private
	 * @var	   array
	 */
	protected $fields;
	/**
	 * Holder for storing properties that were setted via magic setter
	 *
	 * @var	 array
	 * @access	protected
	 */
	protected $dynamicFields;
	/**
	 * The Object Logger used to log the processes in the basic and inherited classes
	 * It is possible to use the debug add error log methods
	 */
	public $logger = null;
	/**
	 * Variable for error handling
	 *
	 * @var	   string
	 */
	protected $errors;
	/**
	 * @var string current class' name
	 */
	protected $className;
	/**
	 *
	 *
	 */
	protected $response;

	/**
	 * Returns API version
	 *
	 * @access private
	 * @return string  $version API version
	 */
	function _apiVersion() {
		return $this->version;
	}

	/**
	 * Returns Curl Response
	 *
	 * @access public
	 * @return array response
	 */
	function getResponse() {
		return $this->response;
	}

	/**
	 * Resets all options to default options
	 *
	 * @return void
	 * @access public
	 */
	function resetOptions() {
		$this->options = $this->defaultOptions;
	}

	/**
	 * Sets an option
	 *
	 * Use this method if you do not want
	 * to set all options in the constructor
	 *
	 * @param string $name	option name
	 * @param mixed	 $value option value
	 *
	 * @return void
	 * @access public
	 */
	function setOption( $name, $value ) {
		$this->logger->debug( 'setOption: Set option ' . $name . ' => ' . $value );
		$this->options[ $name ] = $value;
	}

	/**
	 * Sets several options at once
	 *
	 * Use this method if you do not want
	 * to set all options in the constructor
	 *
	 * @param array $options options array
	 *
	 * @return void
	 * @access public
	 */
	function setOptions( array $options ) {
		$this->options = array_merge( $this->options, $options );
	}

	/**
	 * Returns the URL Alias of the API Class that inherits the OnApp class
	 *
	 * Can be redefined if the API does not use the default alias (the alias
	 * consisting of few fields).
	 * The following example illustrates:
	 *
	 * <code>
	 *	  function getResource() {
	 *		  return "alias/" . $this->_field_name . "/" . $this->_resource;
	 *	  }
	 * </code>
	 *
	 * @param string $action
	 *
	 * @return string API resource
	 */
	function getResource( $action = ONAPP_GETRESOURCE_DEFAULT ) {
		switch( $action ) {
			case ONAPP_GETRESOURCE_LOAD:
			case ONAPP_GETRESOURCE_EDIT:
			case ONAPP_GETRESOURCE_DELETE:
				$resource = $this->getResource() . '/' . $this->_id;
				break;

			case ONAPP_GETRESOURCE_LIST:
			case ONAPP_GETRESOURCE_ADD:
				$resource = $this->getResource();
				break;

			case ONAPP_GETRESOURCE_DEFAULT:
			default:
				$resource = $this->_resource;
		}
		$this->logger->debug( 'getResource( ' . $action . ' ): return ' . $resource );

		return $resource;
	}

	/**
	 * Returns true if the API instance has authentication information set and authentication was succesful
	 *
	 * @return boolean true if authenticated
	 * @access public
	 *
	 * @todo   move to the defaut getter
	 */
	function isAuthenticate() {
		return $this->_is_auth;
	}

	/**
	 * Returns true if the Object was changed and API response was succesfull
	 *
	 * @return boolean true if the Object was changed
	 * @access public
	 *
	 * @todo   move to the defaut getter
	 */
	function isChanged() {
		return $this->_is_changed;
	}

	/**
	 * Returns true if the Object was deleted in the API instance
	 * and API response was succesfull
	 *
	 * @return boolean true if the Object was deleted
	 * @access public
	 *
	 * @todo   move to the defaut getter
	 */
	function isDelete() {
		return $this->_is_deleted;
	}

	/**
	 * Returns Text written to the full class logs
	 *
	 * When the log level is set to debug, the debug messages will be also
	 * included
	 *
	 * @return string All formatted logs
	 * @access public
	 */
	function logs() {
		if( isset( $this->logger ) ) {
			return $this->logger->logs();
		}
	}

	/**
	 * Authorizes users in the system by the specified URL by means of cURL
	 *
	 * To authorize, set the user name and password. Specify the Proxy, if
	 * needed. When authorized, {@link load}, {@link save}, {@link delete} and
	 * {@link getList} methods can be used.
	 *
	 * @param string $url	API URL
	 * @param string $user	user name
	 * @param string $pass	password
	 * @param string $proxy (optional) proxy server
	 *
	 * @return void
	 * @access public
	 */
	function auth( $url, $user, $pass, $proxy = '' ) {
		$this->logger->setDebug( $this->options[ ONAPP_OPTION_DEBUG_MODE ] );

		$this->logger->setTimezone();

		$this->logger->debug( 'auth: Authorization(url => ' . $url . ', user => ' . $user . ', pass => ********).' );

		$this->setOption( ONAPP_OPTION_CURL_URL, $url );
		$this->setOption( ONAPP_OPTION_CURL_PROXY, $proxy );

		$this->_init_curl( $user, $pass );

		$this->setAPIResource( ONAPP_GETRESOURCE_VERSION );

		$response = $this->sendRequest( ONAPP_REQUEST_METHOD_GET );

		if( $response[ 'info' ][ 'http_code' ] == '200' ) {
			$this->setAPIVersion( $response[ 'response_body' ] );

			if( $this->getClassName() != 'OnApp' ) {
				$this->initFields( $this->version );
			}
			$this->setErrors();
			$this->_is_auth = true;
		}
		else {
			switch( $this->options[ ONAPP_OPTION_API_TYPE ] ) {
				case 'xml':
				case 'json':
					$tag = 'version';
					$this->version = null;

					$objCast = new OnApp_Helper_Caster( $this );
					$error = $objCast->unserialize( $this->getClassName(), $response[ 'response_body' ], null, 'errors' );
					break;

				default:
					//todo add CLI check
					$msg = 'FATAL ERROR: Caster for "' . $this->options[ ONAPP_OPTION_API_TYPE ] . '" is not defined'
						. ' in FILE ' . __FILE__ . ' LINE ' . __LINE__ . PHP_EOL . PHP_EOL;
					try {
						throw new Exception( $msg );
					}
					catch( Exception $e ) {
						echo $e->getMessage();
						exit( $this->logger->logs() );
					}
			}
			$this->setErrors( $error );
			$this->_is_auth = false;
		}
	}

	protected function setAPIVersion( $data ) {
		switch( $this->options[ ONAPP_OPTION_API_TYPE ] ) {
			case 'xml':
			case 'json':
				$tag = 'version';
				$this->version = null;

				$objCast = new OnApp_Helper_Caster( $this );
				$this->version = $objCast->unserialize( $this->getClassName(), $data, null, $tag );
				break;

			default:
				//todo add CLI check
				$msg = 'FATAL ERROR: Caster for "' . $this->options[ ONAPP_OPTION_API_TYPE ] . '" is not defined'
					. ' in FILE ' . __FILE__ . ' LINE ' . __LINE__ . PHP_EOL . PHP_EOL;
				try {
					throw new Exception( $msg );
				}
				catch( Exception $e ) {
					echo $e->getMessage();
					exit( $this->logger->logs() );
				}
		}
		$this->version = (float)$this->version;
	}

	public function initFields( $version = null, $className = '' ) {
		if( ! is_null( $version ) ) {
			$this->version = $version;
		}

		if( is_null( $this->fields ) && ( $this->getClassName() != 'OnApp' ) ) {
			$this->logger->debug( 'No fields defined for current API version [ ' . $version . ' ]' );
		}
		elseif( ! is_null( $version ) ) {
			if( $version == $this->version ) {
				if( $this->defaultOptions[ ONAPP_OPTION_DEBUG_MODE ] ) {
					$this->logger->debug( $className . '::initFields, version ' . $version . PHP_EOL . print_r( $this->fields, true ) );
				}
				else {
					$this->logger->add( $className . '::initFields, version ' . $version );
				}
			}
		}

		if( is_null( $this->fields ) && ! in_array( get_called_class(), array( 'OnApp', 'OnApp_Factory' ) ) ) {
			throw new Exception( sprintf(
				"The wrapper class '%s' does not support OnApp version '%s'",
				get_called_class(),
				$version
			) );
		}
	}

	/**
	 * Sets an option for a cURL transfer
	 *
	 * @param string $user		user name
	 * @param string $pass		password
	 * @param string $cookiedir Cookies directory
	 *
	 * @return void
	 * @access private
	 *
	 * @todo   check response from basic URL
	 */
	function _init_curl( $user, $pass, $cookiedir = '' ) {
		$this->logger->debug( "_init_curl: Init Curl (cookiedir => '$cookiedir')." );

		$this->_ch = curl_init();

		//todo ???
		//$this->_is_auth = true;

		if( strlen( $this->options[ ONAPP_OPTION_CURL_PROXY ] ) > 0 ) {
			curl_setopt(
				$this->_ch,
				CURLOPT_PROXY,
				$this->options[ ONAPP_OPTION_CURL_PROXY ]
			);
		}

		curl_setopt( $this->_ch, CURLOPT_SSL_VERIFYPEER, false );
		curl_setopt( $this->_ch, CURLOPT_RETURNTRANSFER, true );
		curl_setopt(
			$this->_ch, CURLOPT_USERPWD,
			$user . ':' . $pass
		);
	}

	/**
	 * Closes a cURL session
	 *
	 * @return void
	 * @access public
	 */
	function close_curl() {
		curl_close( $this->_ch );
	}

	/**
	 * Sets full API path to the variable cURL
	 *
	 * @param string  $resource	   API alias
	 * @param boolean $append_api_version
	 * @param string  $queryString API request
	 *
	 * @return void
	 * @access public
	 */
	function setAPIResource( $resource, $append_api_version = true, $queryString = '' ) {
		$url = $this->options[ ONAPP_OPTION_CURL_URL ];
		$this->logger->add(
			'setAPIResource: Set an option for a cURL transfer (' .
			' url => "' . $url . '", ' .
			' resource => "' . $resource . '", ' .
			' data_type => "' . $this->options[ ONAPP_OPTION_API_TYPE ] . '"' .
			' append_api_version => ' . $this->getAPIVersion() . ',' .
			' queryString => "' . $queryString . '" ).'
		);

		if( $append_api_version ) {
			curl_setopt(
				$this->_ch,
				CURLOPT_URL,
				sprintf(
					'%1$s/%2$s.%3$s?%4$s',
					$url,
					$resource,
					$this->options[ ONAPP_OPTION_API_TYPE ],
					$queryString )
			);
		}
		else {
			curl_setopt(
				$this->_ch,
				CURLOPT_URL,
				sprintf(
					'%1$s/%2$s?%3$s',
					$url,
					$resource,
					$queryString
				)
			);
		}
	}

	/**
	 * Sends API request to the API server and gets response from it
	 *
	 * @param string	 $method
	 * @param array|null $data
	 *
	 * @return array|bool cURL response
	 */
	protected function sendRequest( $method, $data = null ) {
		$alowed_methods = array(
			ONAPP_REQUEST_METHOD_GET,
			ONAPP_REQUEST_METHOD_POST,
			ONAPP_REQUEST_METHOD_PUT,
			ONAPP_REQUEST_METHOD_DELETE,
		);
		if( ! in_array( $method, $alowed_methods ) ) {
			$this->logger->error( 'Wrong request method.' );
		}

		$debug_msg = 'Send ' . $method . ' request.';
		if( $data ) {
			$debug_msg .= ' Request:' . PHP_EOL . print_r( $data, true );
		}
		$this->logger->debug( $debug_msg );

		$http_header = array(
			'Content-Type: ' . $this->options[ ONAPP_OPTION_API_CONTENT ],
			'Accept: ' . $this->options[ ONAPP_OPTION_API_CONTENT ]
		);

		curl_setopt( $this->_ch, CURLOPT_CUSTOMREQUEST, $method );
		switch( $method ) {
			case ONAPP_REQUEST_METHOD_GET:
				curl_setopt( $this->_ch, CURLOPT_HTTPGET, true );

				if( ! is_null( $data ) ) {
					curl_setopt( $this->_ch, CURLOPT_POSTFIELDS, $data );
				}
				else {
					$http_header[ ] = 'Content-Length: 0';
				}
				break;

			case ONAPP_REQUEST_METHOD_POST:
				if( ! is_null( $data ) ) {
					curl_setopt( $this->_ch, CURLOPT_POSTFIELDS, $data );
				}
				break;

			case ONAPP_REQUEST_METHOD_PUT:
				$http_header[ ] = 'Content-Length: ' . strlen( $data );

				if( ! is_null( $data ) ) {
					curl_setopt( $this->_ch, CURLOPT_POSTFIELDS, $data );
				}
				break;

			case ONAPP_REQUEST_METHOD_DELETE:
				if( ! is_null( $data ) ) {
					$http_header[ ] = 'Content-Length: ' . strlen( $data );
					curl_setopt( $this->_ch, CURLOPT_POSTFIELDS, $data );
				}
				break;
		}

		curl_setopt( $this->_ch, CURLOPT_RETURNTRANSFER, true );
		curl_setopt( $this->_ch, CURLOPT_SSL_VERIFYHOST, false );
		curl_setopt( $this->_ch, CURLOPT_HEADER, true );
		curl_setopt( $this->_ch, CURLOPT_HTTPHEADER, $http_header );

		$result = array();
		$result[ 'response_body' ] = curl_exec( $this->_ch );
		$result[ 'info' ] = curl_getinfo( $this->_ch );
		$curlHeaderSize = $result[ 'info' ][ 'header_size' ];
		$result[ 'headers' ] = mb_substr( $result[ 'response_body' ], 0, $curlHeaderSize );
		$result[ 'response_body' ] = mb_substr( $result[ 'response_body' ], $curlHeaderSize );

		if( ! $result[ 'response_body' ] && $method == ONAPP_REQUEST_METHOD_DELETE ||
			! $result[ 'response_body' ] && $method == ONAPP_REQUEST_METHOD_PUT
		) {
			switch( $this->options[ ONAPP_OPTION_API_TYPE ] ) {
				case 'json':
					$result[ 'response_body' ] = '{}';
					break;

				case 'xml':
					$result[ 'response_body' ] = ' ';
					break;

				default:
					$this->logger->error( 'Unsupported API method ' . $this->options[ ONAPP_OPTION_API_TYPE ] );
					break;
			}
		}

		$this->logger->debug( 'Receive Response ' . print_r( $result, true ) );

		if( ! $result[ 'response_body' ] ) {
			$this->logger->debug( 'Response body is empty for method: ' . $method );

			return false;
		}

		$this->response = $result;

		$content_type = $result[ 'info' ][ 'content_type' ];

		if( $content_type == $this->options[ ONAPP_OPTION_API_CONTENT ] . "; " . $this->options[ ONAPP_OPTION_API_CHARSET ] ) {
			switch( $result[ 'info' ][ 'http_code' ] ) {
				case 200:
				case 201:
				case 204:
					break;

				case 422:
				case 404:
					switch( $this->options[ ONAPP_OPTION_API_TYPE ] ) {
						case 'xml':
						case 'json':
							$this->logger->add( 'Response (code => ' . $result[ 'info' ][ 'http_code' ] . ', cast:' . PHP_EOL . $result[ 'response_body' ] );
							break;
					}
					break;

				default:
					$this->logger->warning( 'Response (code => ' . $result[ 'info' ][ 'http_code' ] . ', body: ' . PHP_EOL . $result[ 'response_body' ] );
					$result[ 'errors' ] = $result[ 'response_body' ];
			}
		}
		else {
			$this->logger->add( 'sendRequest: Response:' . PHP_EOL . $result[ 'response_body' ] );
			$result[ 'errors' ] = 'Bad response content type: ' . $content_type;
			$result[ 'error_response' ] = $result[ 'response_body' ];
		}

		$this->_errno_curl( $result[ 'response_body' ] );

		return $result;
	}

	/**
	 *
	 * @param type $label
	 *
	 * @return string
	 */
	public function getHeader( $label = null ) {
		if( ! $label ) {
			return $this->response[ 'headers' ];
		}

		$content = '';

		preg_match_all( '|' . $label . ': (.*)|', $this->response[ 'headers' ], $content );

		return implode( '', $content[ 1 ] );
	}

	/**
	 * The method validates the API request errors
	 *
	 * You will get an error in case of the following error codes:
	 *	 - UNSUPPORTED PROTOCOL
	 *	 - FAILED INIT
	 *	 - URL MALFORMAT
	 *	 - COULDNT RESOLVE PROXY
	 *	 - COULDNT RESOLVE HOST
	 *
	 * @param  string $response_body API Response body
	 *
	 * @return void
	 * @access private
	 */
	function _errno_curl( $response_body ) {
		$error_no = curl_errno( $this->_ch );

		switch( $error_no ) {
			case CURLE_OK:
				// Note: the 0 code does not mean an error, but it means success
				$this->logger->debug( 'Response Body: OK.' . PHP_EOL . $response_body );
				break;

			case CURLE_UNSUPPORTED_PROTOCOL : // 1
			case CURLE_UNSUPPORTED_PROTOCOL: // 2
			case CURLE_FAILED_INIT: // 3
			case CURLE_URL_MALFORMAT: // 4
			case CURLE_URL_MALFORMAT_USER: // 5
			case CURLE_COULDNT_RESOLVE_PROXY: // 6
			case CURLE_COULDNT_RESOLVE_HOST: // 7
				$this->logger->warning(
					'Response Body: Error #' . $error_no,
					__FILE__,
					__LINE__
				);
				break;

			default:
				$this->logger->warning( 'sendRequest: unknown error number ' . $error_no );
		}
	}

	/**
	 * Casts an API response to the Array of Objects or an Object
	 *
	 * @param array $response API response
	 *
	 * @return mixed (Array of Object or Object)
	 */
	protected function _castResponseToClass( $response ) {
		$this->logger->debug( '_castResponseToClass: Cast response in to Object.' );

		if( isset( $response[ 'response_body' ] ) ) {
			$http_code = $response[ 'info' ][ 'http_code' ];

			switch( $http_code ) {
				case 200:
				case 201:
				case 404:
				case 422:
				case 204:
					return $this->castStringToClass( $response );
					break;

				case 500:
					$this->setErrors( 'We\'re sorry, but something went wrong.' );

					return $this;

				default:
					$this->setErrors( 'Bad response ( code => ' . $http_code . ', response => ' . $response[ 'response_body' ] . ' )' );
			}
		}
		else {
			$this->logger->error(
				'castResponseToClass: Can\'t parse ' . $response[ 'response_body' ],
				__FILE__,
				__LINE__
			);
		}
	}

	/**
	 * Casts string (API response body content) to the Object
	 *
	 * @param array $content class string content
	 *
	 * @return mixed array of Objects or Object
	 */
	protected function castStringToClass( array $content ) {
		$className = $this->getClassName();
		$tagMap = $this->fields;

		$this->logger->add( 'castStringToClass: cast data into the ' . $className . ' object.' );

		switch( $this->options[ ONAPP_OPTION_API_TYPE ] ) {
			case 'xml':
			case 'json':
				$root = $this->_tagRoot;
				$data = $content[ 'response_body' ];

				$objCast = new OnApp_Helper_Caster( $this );

				if( $content[ 'info' ][ 'http_code' ] > 201 ) {
					$root = 'errors';
					$errors = $objCast->unserialize( $className, $data, $tagMap, $root );
					$this->setErrors( $errors );

					//todo ????
					//if( empty( $this->errors ) && isset( $content[ 'error_response' ] ) ) {
					//	  $this->setErrors( $content[ 'error_response' ] );
					//}

					return $this;
				}
				else {
					return $objCast->unserialize( $className, $data, $tagMap, $root );
				}

			default:
				$msg = 'FATAL ERROR: Caster for "' . $this->options[ ONAPP_OPTION_API_TYPE ] . '" is not defined'
					. ' in FILE ' . __FILE__ . ' LINE ' . __LINE__ . PHP_EOL . PHP_EOL;
				try {
					throw new Exception( $msg );
				}
				catch( Exception $e ) {
					echo $e->getMessage();
					//todo ???
					exit( $this->logger->logs() );
				}
		}
	}

	/**
	 * Activates action performed with object
	 *
	 * @param string $action_name the name of action
	 *
	 * @access public
	 */
	function activate( $action_name ) {
	}

	/**
	 * Sends an API request to get the Objects. After requesting,
	 * unserializes the received response into the array of Objects
	 *
	 * @param mixed $params
	 * @param mixed $url_args
	 *
	 * @return array|bool the array of Object instances
	 */
	public function getList( $params = null, $url_args = null ) {
		$this->activate( ONAPP_ACTIVATE_GETLIST );

		$this->logger->add( 'Run ' . __METHOD__ );

		$result = $this->sendGet( ONAPP_GETRESOURCE_LIST, $params, $url_args );

		if( ! is_null( $this->getErrorsAsArray() ) ) {
			return false;
		}
		else {
			if( ! is_array( $result ) && ! is_null( $result ) ) {
				$result = array( $result );
			}

			return $result;
		}
	}

	/**
	 * Sends an API request to get the Object after sending,
	 * unserializes the response into an object
	 *
	 * The key field Parameter ID is used to load the Object. You can re-set
	 * this parameter in the class inheriting OnApp class.
	 *
	 * @param integer $id Object id
	 *
	 * @return mixed serialized Object instance from API
	 * @access public
	 */
	function load( $id = null ) {
		$this->activate( ONAPP_ACTIVATE_LOAD );

		if( is_null( $id ) && ! is_null( $this->_id ) ) {
			$id = $this->_id;
		}

		if( is_null( $id ) &&
			isset( $this->_obj ) &&
			! is_null( $this->_obj->_id )
		) {
			$id = $this->_obj->_id;
		}

		if( is_null( $id ) ) {
			$this->logger->error(
				'load: Can\'t set variable ' . $id,
				__FILE__,
				__LINE__
			);
		}

		$this->logger->add( 'load: Load class ( id => ' . $id . ' ).' );

		if( strlen( $id ) > 0 ) {
			$this->_id = $id;

			$this->setAPIResource( $this->getResource( ONAPP_GETRESOURCE_LOAD ) );
			$response = $this->sendRequest( ONAPP_REQUEST_METHOD_GET );
			$result = $this->castStringToClass( $response );

			$this->_obj = $result;
			$this->_id = $this->_obj->_id;

			return $result;
		}
		else {
			$this->logger->error(
				'load: argument id not set.',
				__FILE__,
				__LINE__
			);
		}
	}

	/**
	 * The method saves an Object to your account
	 *
	 * After sending an API request to create an object or change the data in
	 * the existing object, the method checks the response and loads the
	 * exisitng object with the new data.
	 *
	 * This method can be closed for read only objects of the inherited class
	 * <code>
	 *	  function save() {
	 *		  $this->logger->error(
	 *			  "Call to undefined method ".__CLASS__."::save()",
	 *			  __FILE__,
	 *			  __LINE__
	 *		  );
	 *	  }
	 * </code>
	 *
	 * @return void
	 * @access public
	 */
	function save() {
		$this->activate( ONAPP_ACTIVATE_SAVE );

		if( is_null( $this->_id ) ) {
			$obj = $this->_create();
		}
		else {
			$obj = $this->_edit();
		}

		//todo handle errors
		if( isset( $obj ) && ! isset( $obj->errors ) ) {
			$this->load();
		}
	}

	/**
	 * The method creates a new Object
	 *
	 * @return object Serialized API Response
	 * @access private
	 */
	function _create() {
		$this->logger->add( 'Create new Object.' );

		switch( $this->options[ ONAPP_OPTION_API_TYPE ] ) {
			case 'xml':
			case 'json':
				$objCast = new OnApp_Helper_Caster( $this );
				$data = $objCast->serialize( $this->_tagRoot, $this->getFieldsToSend() );
				$this->logger->debug( 'serialize: serialized data:' . PHP_EOL . $data );
				$this->setAPIResource( $this->getResource( ONAPP_GETRESOURCE_ADD ) );
				$response = $this->sendRequest( ONAPP_REQUEST_METHOD_POST, $data );

				$result = $this->_castResponseToClass( $response );
				$this->_obj = $result;
				break;

			default:
				$msg = 'FATAL ERROR: Caster for "' . $this->options[ ONAPP_OPTION_API_TYPE ] . '" is not defined'
					. ' in FILE ' . __FILE__ . ' LINE ' . __LINE__ . PHP_EOL . PHP_EOL;
				try {
					throw new Exception( $msg );
				}
				catch( Exception $e ) {
					echo $e->getMessage();
					//todo ???
					exit( $this->logger->logs() );
				}
		}

		return $result;
	}

	/**
	 * The method edits an existing Object
	 *
	 * @return object Serialized API Response
	 * @access private
	 */
	function _edit() {
		switch( $this->options[ ONAPP_OPTION_API_TYPE ] ) {
			case 'xml':
			case 'json':
				$objCast = new OnApp_Helper_Caster( $this );
				$data = $objCast->serialize( $this->_tagRoot, $this->getFieldsToSend() );
				$this->logger->debug( 'serialize: serialized data:' . PHP_EOL . $data );
				$this->setAPIResource( $this->getResource( ONAPP_GETRESOURCE_EDIT ) );
				$response = $this->sendRequest( ONAPP_REQUEST_METHOD_PUT, $data );

				if( $response[ 'info' ][ 'http_code' ] > 201 ) {
					$this->_castResponseToClass( $response );
				}
				else {
					$this->load( $this->_id );
				}
				break;

			default:
				$msg = 'FATAL ERROR: Caster for "' . $this->options[ ONAPP_OPTION_API_TYPE ] . '" is not defined'
					. ' in FILE ' . __FILE__ . ' LINE ' . __LINE__ . PHP_EOL . PHP_EOL;
				try {
					throw new Exception( $msg );
				}
				catch( Exception $e ) {
					echo $e->getMessage();
					//todo ???
					exit( $this->logger->logs() );
				}
		}
	}

	/**
	 * Creates data fro API response to save or change the object data
	 *
	 * Returns the Hash of Object fields with values
	 *
	 * @return hash of string
	 * @access private
	 */
	protected function getFieldsToSend() {
		$this->logger->debug( 'getFieldsToSend: Prepare data array:' );
		$result = array();

		foreach( $this->fields as $key => $value ) {
			//skip property from request
			if( isset( $value[ ONAPP_FIELD_SKIP_FROM_REQUEST ] ) && $value[ ONAPP_FIELD_SKIP_FROM_REQUEST ] ) {
				//todo add log record
				continue;
			}

			$property = $value[ ONAPP_FIELD_MAP ];
			if( isset( $value[ ONAPP_FIELD_REQUIRED ] ) && $value[ ONAPP_FIELD_REQUIRED ] ) {
				if( isset( $this->$property ) && ! empty( $this->$property ) ) {
					$result[ $key ] = $this->$property;
				}
				elseif( isset( $this->$property ) && is_bool( $this->$property ) ) {
					$result[ $key ] = $this->$property;
				}
				elseif( isset( $this->_obj->$property ) ) {
					$result[ $key ] = $this->_obj->$property;
				}
				elseif( isset( $value[ ONAPP_FIELD_DEFAULT_VALUE ] ) ) {
					$result[ $key ] = $value[ ONAPP_FIELD_DEFAULT_VALUE ];
				}
				else {
					$this->logger->error(
						'getFieldsToSent: Property ' . $property . ' not defined',
						__FILE__,
						__LINE__
					);
				}
			}
			elseif( isset( $this->$property ) ) {
				$result[ $key ] = $this->$property;
			}
			else {
				if( isset( $this->_obj->$property ) ) {
					$result[ $key ] = $this->_obj->$property;
				}
				elseif( isset( $value[ ONAPP_FIELD_DEFAULT_VALUE ] ) ) {
					$result[ $key ] = $value[ ONAPP_FIELD_DEFAULT_VALUE ];
				}
			}

			if( isset( $result[ $key ] ) ) {
				$this->logger->debug( 'getFieldsToSent: set attribute ( ' . $key . ' => ' . print_r( $result[ $key ], true ) . ' ).' );
			}
		}

		return $result;
	}

	/**
	 * Sends an API request to delete an Object from your account
	 *
	 * This method can be closed for read only objects of the inherited class
	 * <code>
	 *	  function delete() {
	 *		  $this->logger->error(
	 *			  "Call to undefined method ".__CLASS__."::delete()",
	 *			  __FILE__,
	 *			  __LINE__
	 *		  );
	 *	  }
	 * </code>
	 *
	 * @return boolean the Object deleted
	 * @access public
	 */
	function delete() {
		$this->activate( ONAPP_ACTIVATE_DELETE );

		$this->logger->add( 'Delete existing Object ( id => ' . $this->_id . ' ).' );

		$this->sendDelete( ONAPP_GETRESOURCE_DELETE );

		if( count( $this->getErrorsAsArray() ) < 1 ) {
			$this->_is_deleted = true;
		}
	}

	function sendPost( $resource, $data = null ) {
		return $this->_action( ONAPP_REQUEST_METHOD_POST, $resource, $data );
	}

	protected function sendGet( $resource, $data = null, $url_args = null ) {
		return $this->_action( ONAPP_REQUEST_METHOD_GET, $resource, $data, $url_args );
	}

	function sendPut( $resource, $data = null ) {
		return $this->_action( ONAPP_REQUEST_METHOD_PUT, $resource, $data );
	}

	function sendDelete( $resource, $data = null ) {
		return $this->_action( ONAPP_REQUEST_METHOD_DELETE, $resource, $data );
	}

	/**
	 * Sends API Requests to realize not base actions
	 *
	 * @param string	 $method
	 * @param string	 $resource
	 * @param array|null $data
	 *
	 * @return bool|mixed (Array of Object or Object)
	 */
	protected function _action( $method, $resource, $data = null, $url_args = null ) {
		switch( $this->options[ ONAPP_OPTION_API_TYPE ] ) {
			case 'xml':
			case 'json':
				if( ! is_null( $data ) ) {
					$objCast = new OnApp_Helper_Caster( $this );
					$data = $objCast->serialize( $data[ 'root' ], $data[ 'data' ] );
					$this->logger->debug( 'Additional parameters: ' . $data );
				}

				$url_args = ( $url_args ) ? preg_replace( '/%5B(0-9){1,4}%5D/', '%5B%5D', http_build_query( $url_args ) ) : '';

				$this->setAPIResource( $this->getResource( $resource ), true, $url_args );

				$response = $this->sendRequest( $method, $data );

				$result = $this->_castResponseToClass( $response );

				if( $response[ 'info' ][ 'http_code' ] > 400 ) {
					if( is_null( $result ) ) {
						$this->_obj = clone $this;
					}
					else {
						$this->_obj->errors = $result->getErrorsAsArray();
					}

					return false;
				}
				else {
					$this->_obj = $result;
				}
				break;

			default:
				$this->logger->error( '_action: Can\'t find serialize and unserialize functions for type (apiVersion => \'' . $this->getAPIVersion() . "').", __FILE__, __LINE__ );
				break;
		}
		return $result;
	}

	public function getClassName() {
		if( is_null( $this->className ) ) {
			return __CLASS__;
		}
		else {
			return $this->className;
		}
	}

	public function getClassFields() {
		return $this->fields;
	}

	public function getAPIVersion() {
		return $this->version;
	}

	/**
	 * Store errors
	 *
	 * @param mixed $errors
	 *
	 * @return void
	 */
	public function setErrors( $errors = null ) {
		if( is_null( $errors ) ) {
			$this->errors = null;
		}
		else {
			$this->errors = (array)$errors;
		}
	}

	/**
	 * Return errors as string
	 *
	 * @param string $glue
	 *
	 * @return string
	 */
	public function getErrorsAsString( $glue = '<br />' ) {
		$errors = '';

		foreach( $this->errors as $key => $value ) {
			if( is_array( $value ) ) {
				foreach( $value as $k => $v ) {
					$errors .= $key . ': ' . $v . $glue;
				}
			}
			else {
				$errors .= $value . $glue;
			}
		}

		$errors = substr( $errors, 0, - strlen( $glue ) );

		return $errors;
	}

	/**
	 * Return errors as array
	 *
	 * @return array
	 */
	public function getErrorsAsArray() {
		return $this->errors;
	}

	/**
	 * Unset unnecessary fields
	 *
	 * @param array $fields fields name
	 *
	 * @return void
	 */
	public function unsetFields( $fields ) {
		foreach( $fields as $field ) {
			unset( $this->fields[ $field ] );
		}
	}

	// getters, setters & other magic stuff //
	public function __construct() {
		$this->options = $this->defaultOptions;
		$this->logger = new OnApp_Helper_Logger;
		$this->className = get_called_class();
	}

	/**
	 * Standard method to handle getting non-existent class' property
	 *
	 * @param string $name property name
	 *
	 * @return mixed
	 */
	public function __get( $name ) {
		// legacy getting errors
		// remove after rewriting the code to use getErrors() method
		// instead of direct access
		switch( $name ) {
			case 'error':
				return $this->getErrorsAsArray();
				break;

			case '_version':
				return $this->getAPIVersion();
				break;
		}

		// legacy vars naming
		if( ! isset( $this->dynamicFields[ $name ] ) ) {
			if( strpos( $name, '_' ) === 0 ) {
				$tmpName = substr( $name, 1 );
			}
			else {
				$tmpName = '_' . $name;
			}

			if( isset( $this->dynamicFields[ $tmpName ] ) ) {
				return $this->dynamicFields[ $tmpName ];
			}
			else {
				return null;
			}
		}

		if( is_object( $this->dynamicFields[ $name ] ) ) {
			if( get_class( $this->dynamicFields[ $name ] ) == 'DataHolder' ) {
				$this->dynamicFields[ $name ] = OnApp_Helper_Caster::unserializeNested( $this->dynamicFields[ $name ] );
			}
		}

		return $this->dynamicFields[ $name ];
	}

	/**
	 * Standard method to handle writing into non-existent class' property
	 *
	 * @param string $name	property name
	 * @param string $value property value
	 *
	 * @return void
	 */
	public function __set( $name, $value ) {
		$this->dynamicFields[ $name ] = $value;
	}

	/**
	 * Standard method to check if property was set via setter
	 *
	 * @param string $name property name
	 *
	 * @return bool			result of checking property
	 */
	public function __isset( $name ) {
		// legacy getting errors
		// remove after rewriting the code to use getErrors() method
		// instead of direct access
		switch( $name ) {
			case 'error':
				return isset( $this->errors );
				break;

			case '_version':
				return isset( $this->version );
				break;
		}

		if( isset( $this->dynamicFields[ $name ] ) ) {
			return true;
		}

		if( strpos( $name, '_' ) === 0 ) {
			$tmpName = substr( $name, 1 );
		}
		else {
			$tmpName = '_' . $name;
		}

		return isset( $this->dynamicFields[ $tmpName ] );
	}

	/**
	 * Standard method to unset property which was set via setter
	 *
	 * @param string $name property name
	 *
	 * @return void
	 */
	public function __unset( $name ) {
		if( ! isset( $this->dynamicFields[ $name ] ) ) {
			if( strpos( $name, '_' ) === 0 ) {
				$tmpName = substr( $name, 1 );
			}
			else {
				$tmpName = '_' . $name;
			}

			if( isset( $this->dynamicFields[ $tmpName ] ) ) {
				unset( $this->dynamicFields[ $tmpName ] );
			}
		}
		else {
			unset( $this->dynamicFields[ $name ] );
		}
	}
}