batch.inc 9.16 KB
Newer Older
1
<?php
2
// $Id$
3 4 5 6 7 8 9 10 11 12 13

/**
 * @file Batch processing API for processes to run in multiple HTTP requests.
 */

/**
 * State based dispatcher for batches.
 */
function _batch_page() {
  $batch =& batch_get();

14
  if (isset($_REQUEST['id']) && $data = db_result(db_query("SELECT batch FROM {batch} WHERE bid = %d AND token = '%s'", $_REQUEST['id'], drupal_get_token($_REQUEST['id'])))) {
15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69
    $batch = unserialize($data);
  }
  else {
    return FALSE;
  }

  // Register database update for end of processing.
  register_shutdown_function('_batch_shutdown');

  $op = isset($_REQUEST['op']) ? $_REQUEST['op'] : '';
  switch ($op) {
    case 'start':
      $output = _batch_start();
      break;

    case 'do':
      $output = _batch_do();
      break;

    case 'do_nojs':
      $output = _batch_progress_page_nojs();
      break;

    case 'finished':
      $output = _batch_finished();
      break;
  }

  return $output;
}

/**
 * Initiate the batch processing
 */
function _batch_start() {
  // Choose between the JS and non-JS version.
  // JS-enabled users are identified through the 'has_js' cookie set in drupal.js.
  // If the user did not visit any JS enabled page during his browser session,
  // he gets the non-JS version...
  if (isset($_COOKIE['has_js']) && $_COOKIE['has_js']) {
    return _batch_progress_page_js();
  }
  else {
    return _batch_progress_page_nojs();
  }
}

/**
 * Batch processing page with JavaScript support.
 */
function _batch_progress_page_js() {
  $batch = batch_get();
  $current_set = _batch_current_set();

  drupal_set_title($current_set['title']);
70
  drupal_add_js('misc/progress.js', 'core', 'header', FALSE, FALSE);
71 72 73 74 75 76 77 78 79 80

  $url = url($batch['url'], array('query' => array('id' => $batch['id'])));
  $js_setting = array(
    'batch' => array(
      'errorMessage' => $current_set['error_message'] .'<br/>'. $batch['error_message'],
      'initMessage' => $current_set['init_message'],
      'uri' => $url,
    ),
  );
  drupal_add_js($js_setting, 'setting');
81
  drupal_add_js('misc/batch.js', 'core', 'header', FALSE, FALSE);
82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163

  $output = '<div id="progress"></div>';
  return $output;
}

/**
 * Do one pass of execution and inform back the browser about progression.
 */
function _batch_do() {
  // HTTP POST required
  if ($_SERVER['REQUEST_METHOD'] != 'POST') {
    drupal_set_message(t('HTTP POST is required.'), 'error');
    drupal_set_title(t('Error'));
    return '';
  }

  list($percentage, $message) = _batch_process();

  drupal_set_header('Content-Type: text/plain; charset=utf-8');
  print drupal_to_js(array('status' => TRUE, 'percentage' => $percentage, 'message' => $message));
  exit();
}

/**
 * Batch processing page without JavaScript support.
 */
function _batch_progress_page_nojs() {
  $batch =& batch_get();
  $current_set = _batch_current_set();

  drupal_set_title($current_set['title']);

  $new_op = 'do_nojs';

  if (!isset($batch['running'])) {
    // This is the first page so return some output immediately.
    $percentage = 0;
    $message = $current_set['init_message'];
    $batch['running'] = TRUE;
  }
  else {
    // This is one of the later requests: do some processing first.

    // Error handling: if PHP dies due to a fatal error (e.g. non-existant
    // function), it will output whatever is in the output buffer,
    // followed by the error message.
    ob_start();
    $fallback = $current_set['error_message'] .'<br/>'. $batch['error_message'];
    $fallback = theme('maintenance_page', $fallback, FALSE);

    // We strip the end of the page using a marker in the template, so any
    // additional HTML output by PHP shows up inside the page rather than
    // below it. While this causes invalid HTML, the same would be true if
    // we didn't, as content is not allowed to appear after </html> anyway.
    list($fallback) = explode('<!--partial-->', $fallback);
    print $fallback;

    list($percentage, $message) = _batch_process($batch);
    if ($percentage == 100) {
      $new_op = 'finished';
    }

    // Processing successful; remove fallback.
    ob_end_clean();
  }

  $url = url($batch['url'], array('query' => array('id' => $batch['id'], 'op' => $new_op)));
  drupal_set_html_head('<meta http-equiv="Refresh" content="0; URL='. $url .'">');
  $output = theme('progress_bar', $percentage, $message);
  return $output;
}

/**
 * Advance batch processing for 1 second (or process the whole batch if it
 * was not set for progressive execution).
 */
function _batch_process() {
  $batch =& batch_get();
  $current_set =& _batch_current_set();

  while (!$current_set['success']) {
    $finished = 1;
164
    $task_message = '';
165 166
    if ((list($function, $args) = reset($current_set['operations'])) && function_exists($function)) {
      // Build the 'batch context' array, execute the function call, and retrieve the user message.
167
      $batch_context = array('sandbox' => &$current_set['sandbox'], 'results' => &$current_set['results'], 'finished' => &$finished, 'message' => &$task_message);
168 169
      call_user_func_array($function, array_merge($args, array(&$batch_context)));
    }
170

171 172 173 174 175 176
    if ($finished == 1) {
      // Make sure this step isn't counted double.
      $finished = 0;
      // Remove the operation, and clear the sandbox to reduce the stored data.
      array_shift($current_set['operations']);
      $current_set['sandbox'] = array();
177
    }
178

179 180 181 182 183 184 185 186
    // Make sure we display progress information about a batch set that
    // actually has operations, and not about a 'control' set (form submit
    // handler).
    $remaining = count($current_set['operations']);
    $progress_message = $current_set['progress_message'];
    $total = $current_set['total'];

    // If the batch set is completed, browse through the remaining sets
Dries's avatar
Dries committed
187
    // until we find one that actually has operations.
188 189
    while (empty($current_set['operations']) && ($current_set['success'] = TRUE) && _batch_next_set()) {
      $current_set =& _batch_current_set();
190
    }
191

192 193 194 195 196 197 198 199 200 201 202 203 204 205 206
    // Progressive mode : stop after 1 second
    if ($batch['progressive'] && timer_read('page') > 1000) {
      break;
    }
  }

  if ($batch['progressive']) {
    $current    = $total - $remaining + $finished;
    $percentage = $total ? floor($current / $total * 100) : 100;
    $values = array(
      '@remaining'  => $remaining,
      '@total'      => $total,
      '@current'    => floor($current),
      '@percentage' => $percentage,
      );
207
    $message = strtr($progress_message, $values) .'<br/>';
208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227
    $message.= $task_message ? $task_message : '&nbsp';

    return array($percentage, $message);
  }
  else {
    return _batch_finished();
  }

}

/**
 * Retrieve the batch set being currently processed.
 */
function &_batch_current_set() {
  $batch =& batch_get();
  return $batch['sets'][$batch['current_set']];
}

/**
 * Move execution to the next batch set if any, executing the stored
228 229
 * form _submit handlers along the way (thus possibly inserting
 * additional batch sets)
230 231 232
 */
function _batch_next_set() {
  $batch =& batch_get();
233
  if (isset($batch['sets'][$batch['current_set'] + 1])) {
234 235
    $batch['current_set']++;
    $current_set =& _batch_current_set();
236 237 238
    if (isset($current_set['form_submit']) && ($function = $current_set['form_submit']) && function_exists($function)) {
      // We use our stored copies of $form and $form_state, to account for
      // possible alteration by the submit handlers.
Dries's avatar
Dries committed
239
      $function($batch['form'], $batch['form_state']);
240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269
    }
    return TRUE;
  }
}

/**
 * End the batch :
 * Call the 'finished' callbacks to allow custom handling of results,
 * and resolve page redirection.
 */
function _batch_finished() {
  $batch =& batch_get();

  // Execute the 'finished' callbacks.
  foreach($batch['sets'] as $key => $batch_set) {
    if (isset($batch_set['finished']) && function_exists($batch_set['finished'])) {
      $batch_set['finished']($batch_set['success'], $batch_set['results'], $batch_set['operations']);
    }
  }

  // Cleanup the batch table and unset the global $batch variable.
  db_query("DELETE FROM {batch} WHERE bid = %d", $batch['id']);
  $_batch = $batch;
  $batch = NULL;

  // Redirect if needed.
  if ($_batch['progressive']) {
    if (isset($_batch['destination'])) {
      $_REQUEST['destination'] = $_batch['destination'];
    }
270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290

    // Use $_batch['form_state']['redirect'], or $_batch['redirect'], or $_batch['source_page'].
    if (isset($_batch['form_state']['redirect'])) {
      $redirect = $_batch['form_state']['redirect'];
    }
    elseif (isset($_batch['redirect'])) {
      $redirect = $_batch['redirect'];
    }
    else {
      $redirect = $_batch['source_page'];
    }

    // Let drupal_redirect_form handle redirection logic.
    $form = isset($batch['form']) ? $batch['form'] : array();
    if (empty($_batch['form_state']['rebuild']) && empty($_batch['form_state']['storage'])) {
      drupal_redirect_form($form, $redirect);
    }

    // We get here if $form['#redirect'] was FALSE, or if
    // Save the final $form_state value, Redirect to the originating page.
    $_SESSION['batch_form_state'] = $_batch['form_state'];
291 292 293 294 295
    drupal_goto($_batch['source_page']);
  }
}

/**
Dries's avatar
Dries committed
296
 * Store the batch data for next request, or clear the table if the batch is finished.
297 298 299 300 301 302
 */
function _batch_shutdown() {
  if ($batch = batch_get()) {
    db_query("UPDATE {batch} SET batch = '%s' WHERE bid = %d", serialize($batch), $batch['id']);
  }
}