<?php
// $Id: ab.module,v 1.3 2008-09-22 15:14:50 tjholowaychuk Exp $

/**
 * @file
 * ApacheBench support and report generator.
 */

/* -----------------------------------------------------------------

  Hook Implementations

------------------------------------------------------------------ */

/**
 * Implementation of hook_perm().
 */
function ab_perm() {
  return array('administer ab', 'view ab reports');
}

/**
 * Implementation of hook_menu().
 */
function ab_menu() {
  $items = array();

  $items['admin/reports/ab'] = array(
      'title' => 'ApacheBench Reports',
      'page callback' => 'ab_reports', 
      'access arguments' => array('view ab reports'), 
      'file' => 'ab.admin.inc',
    );
  $items['admin/settings/ab'] = array(
      'title' => 'ApacheBench',
      'page callback' => 'drupal_get_form', 
      'page arguments' => array('ab_settings'), 
      'access arguments' => array('administer ab'), 
      'file' => 'ab.admin.inc',
    );
 
  return $items;
}

/**
 * Implementation of hook_cron().
 */
function ab_cron() {
  if ($last_run = variable_get('cron_last', FALSE)){
		$frequency = variable_get('ab_frequency', 0);
	  $last_run_hours = floor((time() - $last_run) / (60 * 60));

	  // Ensure we can invoke ab
	  if ($frequency <= 0 || $last_run_hours <= $frequency){
		  return;
	  }
	 
	  // Perform tests
	  $uris = explode("\n", variable_get('ab_uris', ''));
	  // @todo allow $uri(s) for ab().
	  foreach((array) $uris AS $uri){
		  ab(trim($uri), variable_get('ab_requests', 100), variable_get('ab_concurrency', 25), TRUE); 
	  }
	 
	  // Log success
	  watchdog('ab', 'ApacheBench invoked on %count uris.', array('%count' => count($uris)), WATCHDOG_INFO);
	}
}

/* -----------------------------------------------------------------

  Public API

------------------------------------------------------------------ */

/**
 * Invoke ApacheBench
 *
 * @param string $uri
 *   Valid absolute URI and path such as 'http://vision-media.ca/', 
 *   note the trailing slash (/).
 *
 * @param int $requests
 *   (optional) Total number of requests.
 *	
 * @param int $concurrency
 *   (optional) Concurrency of requests.
 *
 * @param bool $store
 *   (optional) Bool indicating database storage for reporting.
 *
 * @return mixed
 *   - success: Array of results
 *   - failure: int
 */
function ab($uri, $requests = 100, $concurrency = 25, $store = FALSE) {
	$results = array();
	
	// Ensure concurrency is larger than requests
  if ($concurrency > $requests){
	  return -1;
  }

  // Preven malicious args
  if (!is_numeric($concurrency) || !is_numeric($requests)){
	  return -3;
  }

  // Ensure a valid uri
  if (!valid_url($uri, TRUE)){
	  return -2;
  }

  $results = ab_parse_output(shell_exec("ab -n {$requests} -c {$concurrency} {$uri}"));

  // Store data
  if ($store === TRUE){
	  $args = array();
	  $args[] = $results['complete_requests'];
	  $args[] = $results['document_length'];
	  $args[] = $results['failed_requests'];
	  $args[] = $results['total_transferred'];
	  $args[] = $results['html_transferred'];
	  $args[] = $results['requests_per_second'];
	  $args[] = $results['time_taken_for_tests'];
	  $args[] = $uri;
	  $args[] = $concurrency;
	  $args[] = $requests;
	  $args[] = time(); 
	  db_query("
		  	INSERT INTO {ab_results} 
		  	SET 
		  		rid = '',  
		  		complete_requests = %d, 
		  		document_length = %d, 
		  		failed_requests = %d, 
		  		total_transferred = %d, 
		  		html_transferred = %d, 
		  		requests_per_second = %d, 
		  		time_taken_for_tests = %f, 
		      uri = '%s',
		  		concurrency = %d, 
					requests = %d, 
					created = %d
			", $args);
  }

  return $results;
}

/**
 * Clear all ab results.
 */
function ab_clear_all() {
  db_query("DELETE FROM {ab_results}");
}

/**
 * Parse ab invocation output.
 *
 * @param string $output
 * 
 * @return array
 */
function ab_parse_output($output) {
	$results = array();
	
	$cols = array();
	$cols[] = 'complete requests';
	$cols[] = 'document length';
	$cols[] = 'failed requests';
	$cols[] = 'total transferred';
	$cols[] = 'html transferred';
	$cols[] = 'requests per second';
	$cols[] = 'time taken for tests';
	
	preg_match_all('!('. implode('|', $cols) . '):\s+([0-9\.]+)!i', $output, $matches, PREG_SET_ORDER);
  foreach((array) $matches AS $match){
	  $results[drupal_strtolower(strtr($match[1], ' ', '_'))] = $match[2];
  }

  return $results;
}

/**
 * Require ABChart class.
 */
function ab_require_chart() {
	if (module_exists('open_flash_chart_api')){
    require_once(dirname(__FILE__) . '/ab.chart.inc');
  }
}