batch.inc 11.2 KB
Newer Older
1
<?php
2
// $Id$
3 4 5 6 7 8

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

/**
9
 * State-based dispatcher for the batch processing page.
10 11 12 13
 */
function _batch_page() {
  $batch =& batch_get();

14
  // Retrieve the current state of batch from db.
15
  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'])))) {
16 17 18 19 20 21 22 23 24 25
    $batch = unserialize($data);
  }
  else {
    return FALSE;
  }

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

  $op = isset($_REQUEST['op']) ? $_REQUEST['op'] : '';
26
  $output = NULL;
27 28 29 30 31 32
  switch ($op) {
    case 'start':
      $output = _batch_start();
      break;

    case 'do':
33
      // JS-version AJAX callback.
34
      _batch_do();
35 36 37
      break;

    case 'do_nojs':
38
      // Non-JS progress page.
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 70 71
      $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();

72 73 74
  // The first batch set gets to set the page title
  // and the initialization and error messages.
  $current_set = _batch_current_set();
75
  drupal_set_title($current_set['title']);
76
  drupal_add_js('misc/progress.js', 'core', 'header', FALSE, FALSE);
77 78 79 80 81 82 83 84 85 86

  $url = url($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');
87
  drupal_add_js('misc/batch.js', 'core', 'header', FALSE, FALSE);
88 89 90 91 92 93

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

/**
94 95
 * Do one pass of execution and inform back the browser about progression
 * (used for JavaScript-mode only).
96 97 98 99 100 101 102 103 104
 */
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 '';
  }

105
  // Perform actual processing.
106 107
  list($percentage, $message) = _batch_process();

108
  drupal_json(array('status' => TRUE, 'percentage' => $percentage, 'message' => $message));
109 110 111 112 113 114 115 116 117 118 119 120 121 122
}

/**
 * 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'])) {
123
    // This is the first page so we return some output immediately.
124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144
    $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;

145
    // Perform actual processing.
146 147 148 149 150
    list($percentage, $message) = _batch_process($batch);
    if ($percentage == 100) {
      $new_op = 'finished';
    }

151
    // PHP did not die : remove the fallback output.
152 153 154 155 156 157 158 159 160 161 162
    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
163
 * was not set for progressive execution - e.g forms submitted by drupal_execute).
164 165 166 167
 */
function _batch_process() {
  $batch =& batch_get();
  $current_set =& _batch_current_set();
168
  $set_changed = TRUE;
169

170 171 172 173
  if ($batch['progressive']) {
    timer_start('batch_processing');
  }

174
  while (!$current_set['success']) {
175 176 177 178 179 180 181
    // If this is the first time we iterate this batch set in the current
    // request, we check if it requires an additional file for functions
    // definitions.
    if ($set_changed && isset($current_set['file']) && is_file($current_set['file'])) {
      include_once($current_set['file']);
    }

182
    $finished = 1;
183
    $task_message = '';
184
    if ((list($function, $args) = reset($current_set['operations'])) && function_exists($function)) {
185 186
      // Build the 'context' array, execute the function call,
      // and retrieve the user message.
187
      $batch_context = array('sandbox' => &$current_set['sandbox'], 'results' => &$current_set['results'], 'finished' => &$finished, 'message' => &$task_message);
188
      // Process the current operation.
189 190
      call_user_func_array($function, array_merge($args, array(&$batch_context)));
    }
191

192
    if ($finished == 1) {
193
      // Make sure this step isn't counted double when computing $current.
194
      $finished = 0;
195
      // Remove the operation and clear the sandbox.
196 197
      array_shift($current_set['operations']);
      $current_set['sandbox'] = array();
198
    }
199

200
    // If the batch set is completed, browse through the remaining sets,
201 202 203
    // executing 'control sets' (stored form submit handlers) along the way -
    // this might in turn insert new batch sets.
    // Stop when we find a set that actually has operations.
204 205
    $set_changed = FALSE;
    $old_set = $current_set;
206 207
    while (empty($current_set['operations']) && ($current_set['success'] = TRUE) && _batch_next_set()) {
      $current_set =& _batch_current_set();
208
      $set_changed = TRUE;
209
    }
210 211
    // At this point, either $current_set is a 'real' batch set (has operations),
    // or all sets have been completed.
212

213
    // If we're in progressive mode, stop after 1 second.
214
    if ($batch['progressive'] && timer_read('batch_processing') > 1000) {
215 216 217 218 219
      break;
    }
  }

  if ($batch['progressive']) {
220 221 222 223
    // Gather progress information.

    // Reporting 100% progress will cause the whole batch to be considered
    // processed. If processing was paused right after moving to a new set,
224
    // we have to use the info from the new (unprocessed) one.
225 226 227 228 229 230 231 232 233 234 235 236 237
    if ($set_changed && isset($current_set['operations'])) {
      // Processing will continue with a fresh batch set.
      $remaining = count($current_set['operations']);
      $total = $current_set['total'];
      $progress_message = $current_set['init_message'];
      $task_message = '';
    }
    else {
      $remaining = count($old_set['operations']);
      $total = $old_set['total'];
      $progress_message = $old_set['progress_message'];
    }

238 239 240 241 242 243 244 245
    $current    = $total - $remaining + $finished;
    $percentage = $total ? floor($current / $total * 100) : 100;
    $values = array(
      '@remaining'  => $remaining,
      '@total'      => $total,
      '@current'    => floor($current),
      '@percentage' => $percentage,
      );
246
    $message = strtr($progress_message, $values) .'<br/>';
247
    $message .= $task_message ? $task_message : '&nbsp';
248 249 250 251

    return array($percentage, $message);
  }
  else {
252
    // If we're not in progressive mode, the whole batch has been processed by now.
253 254 255 256 257 258 259 260 261 262 263 264 265 266 267
    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
268
 * form _submit handlers along the way (thus possibly inserting
269
 * additional batch sets).
270 271 272
 */
function _batch_next_set() {
  $batch =& batch_get();
273
  if (isset($batch['sets'][$batch['current_set'] + 1])) {
274 275
    $batch['current_set']++;
    $current_set =& _batch_current_set();
276 277 278
    if (isset($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
279
      $function($batch['form'], $batch['form_state']);
280 281 282 283 284 285
    }
    return TRUE;
  }
}

/**
286
 * End the batch processing:
287 288 289 290 291 292
 * Call the 'finished' callbacks to allow custom handling of results,
 * and resolve page redirection.
 */
function _batch_finished() {
  $batch =& batch_get();

293 294 295 296 297 298 299 300 301 302
  // Execute the 'finished' callbacks for each batch set.
  foreach($batch['sets'] as $key => $batch_set) {
    if (isset($batch_set['finished'])) {
      // Check if the set requires an additional file for functions definitions.
      if (isset($batch_set['file']) && is_file($batch_set['file'])) {
        include_once($batch_set['file']);
      }
      if (function_exists($batch_set['finished'])) {
        $batch_set['finished']($batch_set['success'], $batch_set['results'], $batch_set['operations']);
      }
303 304 305 306
    }
  }

  // Cleanup the batch table and unset the global $batch variable.
307 308 309
  if ($batch['progressive']) {
    db_query("DELETE FROM {batch} WHERE bid = %d", $batch['id']);
  }
310 311 312 313 314
  $_batch = $batch;
  $batch = NULL;

  // Redirect if needed.
  if ($_batch['progressive']) {
315
    // Put back the 'destination' that was saved in batch_process().
316 317 318
    if (isset($_batch['destination'])) {
      $_REQUEST['destination'] = $_batch['destination'];
    }
319

320 321
    // Use $_batch['form_state']['redirect'], or $_batch['redirect'],
    // or $_batch['source_page'].
322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337
    if (isset($_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);
    }

338 339 340
    // We get here if $form['#redirect'] was FALSE, or if the form is a
    // multi-step form. We save the final $form_state value to be retrieved
    // by drupal_get_form, and we redirect to the originating page.
341
    $_SESSION['batch_form_state'] = $_batch['form_state'];
342 343 344 345 346
    drupal_goto($_batch['source_page']);
  }
}

/**
347 348
 * Shutdown function: store the batch data for next request,
 * or clear the table if the batch is finished.
349 350 351 352 353 354
 */
function _batch_shutdown() {
  if ($batch = batch_get()) {
    db_query("UPDATE {batch} SET batch = '%s' WHERE bid = %d", serialize($batch), $batch['id']);
  }
}