batch.inc
Batch processing API for processes to run in multiple HTTP requests.
File
drupal-6.x/includes/batch.incView source
- <?php
-
- /**
- * @file Batch processing API for processes to run in multiple HTTP requests.
- */
-
- /**
- * State-based dispatcher for the batch processing page.
- */
- function _batch_page() {
- $batch =& batch_get();
-
- // Retrieve the current state of batch from db.
- if (isset($_REQUEST['id']) && $data = db_result(db_query("SELECT batch FROM {batch} WHERE bid = %d AND token = '%s'", $_REQUEST['id'], drupal_get_token($_REQUEST['id'])))) {
- $batch = unserialize($data);
- }
- else {
- return FALSE;
- }
-
- // Register database update for end of processing.
- register_shutdown_function('_batch_shutdown');
-
- $op = isset($_REQUEST['op']) ? $_REQUEST['op'] : '';
- $output = NULL;
- switch ($op) {
- case 'start':
- $output = _batch_start();
- break;
-
- case 'do':
- // JS-version AJAX callback.
- _batch_do();
- break;
-
- case 'do_nojs':
- // Non-JS progress page.
- $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();
-
- // The first batch set gets to set the page title
- // and the initialization and error messages.
- $current_set = _batch_current_set();
- drupal_set_title($current_set['title']);
- drupal_add_js('misc/progress.js', 'core', 'header', FALSE, FALSE);
-
- $url = url($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');
- drupal_add_js('misc/batch.js', 'core', 'header', FALSE, FALSE);
-
- $output = '<div id="progress"></div>';
- return $output;
- }
-
- /**
- * Do one pass of execution and inform back the browser about progression
- * (used for JavaScript-mode only).
- */
- function _batch_do() {
- // HTTP POST required
- if ($_SERVER['REQUEST_METHOD'] != 'POST') {
- drupal_set_message(t('HTTP POST is required.'), 'error');
- drupal_set_title(t('Error'));
- return '';
- }
-
- // Perform actual processing.
- list($percentage, $message) = _batch_process();
-
- drupal_json(array('status' => TRUE, 'percentage' => $percentage, 'message' => $message));
- }
-
- /**
- * 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 we 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'];
- drupal_maintenance_theme();
- $fallback = theme('maintenance_page', $fallback, FALSE, FALSE);
-
- // We strip the end of the page using a marker in the template, so any
- // additional HTML output by PHP shows up inside the page rather than
- // below it. While this causes invalid HTML, the same would be true if
- // we didn't, as content is not allowed to appear after </html> anyway.
- list($fallback) = explode('<!--partial-->', $fallback);
- print $fallback;
-
- // Perform actual processing.
- list($percentage, $message) = _batch_process($batch);
- if ($percentage == 100) {
- $new_op = 'finished';
- }
-
- // PHP did not die : remove the fallback output.
- 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 - e.g forms submitted by drupal_execute).
- */
- function _batch_process() {
- $batch =& batch_get();
- $current_set =& _batch_current_set();
- $set_changed = TRUE;
-
- if ($batch['progressive']) {
- timer_start('batch_processing');
- }
-
- while (!$current_set['success']) {
- // If this is the first time we iterate this batch set in the current
- // request, we check if it requires an additional file for functions
- // definitions.
- if ($set_changed && isset($current_set['file']) && is_file($current_set['file'])) {
- include_once($current_set['file']);
- }
-
- $finished = 1;
- $task_message = '';
- if ((list($function, $args) = reset($current_set['operations'])) && function_exists($function)) {
- // Build the 'context' array, execute the function call,
- // and retrieve the user message.
- $batch_context = array('sandbox' => &$current_set['sandbox'], 'results' => &$current_set['results'], 'finished' => &$finished, 'message' => &$task_message);
- // Process the current operation.
- call_user_func_array($function, array_merge($args, array(&$batch_context)));
- }
-
- if ($finished >= 1) {
- // Make sure this step isn't counted double when computing $current.
- $finished = 0;
- // Remove the operation and clear the sandbox.
- array_shift($current_set['operations']);
- $current_set['sandbox'] = array();
- }
-
- // If the batch set is completed, browse through the remaining sets,
- // 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.
- $set_changed = FALSE;
- $old_set = $current_set;
- while (empty($current_set['operations']) && ($current_set['success'] = TRUE) && _batch_next_set()) {
- $current_set =& _batch_current_set();
- $set_changed = TRUE;
- }
- // At this point, either $current_set is a 'real' batch set (has operations),
- // or all sets have been completed.
-
- // If we're in progressive mode, stop after 1 second.
- if ($batch['progressive'] && timer_read('batch_processing') > 1000) {
- break;
- }
- }
-
- if ($batch['progressive']) {
- // Gather progress information.
-
- // Reporting 100% progress will cause the whole batch to be considered
- // processed. If processing was paused right after moving to a new set,
- // we have to use the info from the new (unprocessed) one.
- if ($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'];
- }
-
- $current = $total - $remaining + $finished;
- $percentage = $total ? floor($current / $total * 100) : 100;
- $values = array(
- '@remaining' => $remaining,
- '@total' => $total,
- '@current' => floor($current),
- '@percentage' => $percentage,
- );
- $message = strtr($progress_message, $values) .'<br/>';
- $message .= $task_message ? $task_message : ' ';
-
- return array($percentage, $message);
- }
- else {
- // If we're not in progressive mode, the whole batch has been processed by now.
- 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
- * form _submit handlers along the way (thus possibly inserting
- * additional batch sets).
- */
- function _batch_next_set() {
- $batch =& batch_get();
- if (isset($batch['sets'][$batch['current_set'] + 1])) {
- $batch['current_set']++;
- $current_set =& _batch_current_set();
- if (isset($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.
- $function($batch['form'], $batch['form_state']);
- }
- return TRUE;
- }
- }
-
- /**
- * End the batch processing:
- * Call the 'finished' callbacks to allow custom handling of results,
- * and resolve page redirection.
- */
- function _batch_finished() {
- $batch =& batch_get();
-
- // Execute the 'finished' callbacks for each batch set.
- foreach ($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']);
- }
- }
- }
-
- // Cleanup the batch table and unset the global $batch variable.
- if ($batch['progressive']) {
- db_query("DELETE FROM {batch} WHERE bid = %d", $batch['id']);
- }
- $_batch = $batch;
- $batch = NULL;
-
- // Redirect if needed.
- if ($_batch['progressive']) {
- // Put back the 'destination' that was saved in batch_process().
- if (isset($_batch['destination'])) {
- $_REQUEST['destination'] = $_batch['destination'];
- }
-
- // 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 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.
- $_SESSION['batch_form_state'] = $_batch['form_state'];
- drupal_goto($_batch['source_page']);
- }
- }
-
- /**
- * Shutdown function: store the batch data for next request,
- * or clear the table if the batch is finished.
- */
- function _batch_shutdown() {
- if ($batch = batch_get()) {
- db_query("UPDATE {batch} SET batch = '%s' WHERE bid = %d", serialize($batch), $batch['id']);
- }
- }