<?php
/**
 * TestURL
 * 
 * This class provides an easy way yo do simple functional tests on different urls.
 * The user can set the logging and email variables within the class definition.
 * Test URL can test whether the response given by a certain url matches an expected group of
 * headers or an expected response code (200,404,etc.)
 * 
 * USAGE
 * 
 * Testing a single url to make sure its alive
 * 
 * 	$suite = new TestURL("http://www.quirkey.com/",200);
 * 	$suite->test();
 * 
 * The url "http://www.quirkey.com" is requested and if the response code is 200 a success message 
 * will be logged in the log file specified. If an error occurs, the script attempts to  send an email using 
 * the options provided in the class definition
 * 
 * 
 * @author Aaron Quint
 * @url http://www.quirkey.com/blog/
 **/


require_once 'Mail.php';
require_once 'HTTP/Request.php';

class TestURL {
	
	// url to test
	var $test_urls;
	
	var $current_url;
	
	// expected response code
	var $response_code;
	//expected response headers
	var $response_headers;
	
	var $request;
	var $response;
	
	// Email info
	var $from_email = "ADMIN EMAIL ADDRESS";// The address error mail will come from
	var $to_email = "MY EMAIL ADDRESS"; //
	
	// Mail Parameters - for the PEAR Mail Class
	var $mail_backend = "smtp";//set to your host sender - smtp/sendmail/etc...
	var $mail_params = array('host' => 'SMTPHOST');//Set to your host parameters
	
	
	// Place to log the different requests
	var $log_file = 'test_url_log';
	
	// how should the time format look (using strftime())
	var $log_time_format = "[%D - %T] ";
	

	/**
	 * TestURL()
	 * constructor - sets up a test 
	 *
	 * @return void
	 **/
	function TestURL($test_urls, $response_code = false, $response_headers = false) {
		$this->test_urls = $test_urls;
		$this->response_code = $response_code;
		$this->response_headers = $response_headers;
	}
	
	
	/**
	 * test()
	 * after a TestURL object is initialized this guy runs the test
	 * and evaluates the responses
	 * 
	 * @param print_log	whether or not to print the output of the tests
	 * @return void
	 **/
	function test($print_log = false) {
		// if were only checking one url - force it into an array
		// so we can test them all in the same way
		if (!is_array($this->test_urls)) {
			$test_url = $this->test_urls;
			$this->test_urls = array($test_url);
		}
		// go through the urls and test them
		foreach ($this->test_urls as $url) {
			$this->current_url = $url;
			$this->ping();
			$this->validateResponse($print_log);
		}
	}
	
	/**
	 * ping()
	 * ping a url provided by $this->current_url and collect the response
	 * makes good use of the HTTP_Request class 
	 *
	 * @return void
	 **/
	function ping() {
		// set up request and send it
		$this->request =& new HTTP_Request($this->current_url);
		$this->response = $this->request->sendRequest();
	}
	
	/**
	 * vaildateResponse()
	 * parses the response after a ping is sent. If an error occurs an email alert is sent.
	 * all action is logged to a file
	 * 
     * @param print_log	whether or not to print the output of the tests
	 * @return boolean	test Succeess?
	 **/
	function validateResponse($print_log) {
		if (!$this->response) {
			$message = "Unkown Error:" . $this->current_url;
			$this->sendErrorEmail($message);
			$this->logToFile($message);
			if ($print_log) { echo $message . "\n"; }
			return false;
		}
		
		// Check if response is a Pear Error
		if (PEAR::isError($this->response)) {
		    $message = "PEAR Error:" . $this->current_url . ":" . $this->response->getMessage();
			$this->sendErrorEmail($message);
			$this->logToFile($message);
			if ($print_log) { echo $message . "\n"; }
			return false;
		} 
		
		//Check if response code doesnt match expected code
		if ($this->response_code && $this->request->getResponseCode() != $this->response_code) {
			$message = "Wrong Response Code - Expected {$this->response_code}, Got " . 
								$this->request->getResponseCode() . ": " . $this->current_url;
			$this->sendErrorEmail($message);
			$this->logToFile($message);
			if ($print_log) { echo $message . "\n"; }
			return false;
		}
		
		// Check is expected headers match
		if ($this->response_headers) {
			foreach ($this->response_headers as $header => $val) {
				if (!($val == $this->request->getResponseHeader($header))) {
					//header doesnt match
					$message = "Headers dont match - Expected {$header}: {$val}, Got {$header}: " . 
										$this->request->getResponseHeader($header) . ": " . $this->current_url;
					$this->sendErrorEmail($message);
					$this->logToFile($message);
					if ($print_log) { echo $message . "\n"; }
					return false;
				}
			}
		}
		
		// Tests passed 
		// log success return true
		$message = "Success: " . $this->current_url;
		$this->logToFile($message);
		if ($print_log) { echo $message . "\n"; }
		return true;
		
	}
	
	/**
	 * logToFile()
	 * Logs a message to the file provided in the class def ($this->log_file)
	 * 
	 * @return void
	 **/
	function logToFile($message) {
		// open the file for appending
		$fp = fopen($this->log_file,'a');
		// prepend time to message
		$message = strftime($this->log_time_format,time()) . $message . "\n";
		// write to file
		fwrite($fp,$message);
		//close the file
		fclose($fp);
	}
	
	/**
	 * sendErrorEmail()
	 * Sends a log message to the email address in the class def ($this->to_email)
	 * also uses the params for the mail server set in the class def
	 * 
	 * @return void
	 **/
	function sendErrorEmail($message) {
		
		$headers['To'] = $this->to_email;
		$headers['From'] = $this->from_email;
		$headers['Subject'] = "[TestURL] Error";

		$body = strftime($this->log_time_format,time()) . $message  . "\n";

		$message =& Mail::factory($this->mail_backend,$this->mail_params);

		$res = $message->send($this->to_email, $headers, $body);

		return $res;	
	}
}


?>