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pdf_to_imagefield.module in PDF to ImageField 6

Same filename and directory in other branches
  1. 6.2 pdf_to_imagefield.module
  2. 7 pdf_to_imagefield.module

PDF to ImageField core hooks and menu callbacks.

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pdf_to_imagefield.module
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<?php

/**
 * @file
 * PDF to ImageField core hooks and menu callbacks.
 */

/**
 * Implementation of hook_menu().
 */
function pdf_to_imagefield_menu() {
  $items = array();
  $items['admin/settings/pdf_to_imagefield'] = array(
    'title' => 'PDF to ImageField',
    'description' => 'Allow users to configure pdf conversion settings',
    'page callback' => 'drupal_get_form',
    'page arguments' => array(
      'pdf_to_imagefield_settings_form',
    ),
    'access arguments' => array(
      'administer site configuration',
    ),
    'weight' => 1,
  );
  return $items;
}

/**
 * Implementation of hook_theme().
 */
function pdf_to_imagefield_theme() {
  return array(
    // pdf_to_imagefield_widget form element type theme function.
    'pdf_to_imagefield_widget' => array(
      'arguments' => array(
        'element' => NULL,
      ),
    ),
    // Use to generate a preview (admin view) of an imagefield item for use in
    // field item forms and filefield widgets. Invoked by filefield_widget_process.
    'pdf_to_imagefield_widget_preview' => array(
      'arguments' => array(
        'item' => NULL,
      ),
    ),
  );
}

/**
 * Implementation of hook_cron().
 */
function pdf_to_imagefield_cron() {
  $result = db_query_range('SELECT * FROM {pdf_to_imagefield} WHERE finished = 0', variable_get('pdf_to_imagefield_convert_pdf', 1), 0, 1);
  while ($file = db_fetch_object($result)) {
    $pdf = field_file_load($file->fid);
    foreach (filefield_get_field_list(NULL, $file->field) as $fieldname => $field) {
      $images = pdf_to_imagefield_convert_pages($file, pdf_to_imagefield_widget_file_path($field), $pdf);
      pdf_to_imagefield_save_converted($images, $field, $pdf);
    }
  }
}

/**
 * Implementation of hook_elements().
 */
function pdf_to_imagefield_elements() {
  $elements = array();

  // An PDF to ImageField is really just a FileField.
  $filefield_elements = module_invoke('filefield', 'elements');
  $elements['pdf_to_imagefield_widget'] = $filefield_elements['filefield_widget'];
  $elements['pdf_to_imagefield_widget']['#process'][] = 'pdf_to_imagefield_widget_process';
  return $elements;
}

/**
 * Implementation of CCK's hook_widget_info().
 */
function pdf_to_imagefield_widget_info() {
  $module_path = drupal_get_path('module', 'pdf_to_imagefield');
  return array(
    'pdf_to_imagefield_widget' => array(
      'label' => t('PDF to ImageField'),
      'field types' => array(
        'filefield',
      ),
      'multiple values' => CONTENT_HANDLE_CORE,
      'callbacks' => array(
        'default value' => CONTENT_CALLBACK_CUSTOM,
      ),
      'description' => t('An edit widget for pdf files, including functionality to convert pdf pages to ImageField files.'),
    ),
  );
}

/**
 * Implementation of CCK's hook_widget_settings().
 */
function pdf_to_imagefield_widget_settings($op, $widget) {
  switch ($op) {
    case 'form':
      return pdf_to_imagefield_widget_settings_form($widget);
    case 'validate':
      return pdf_to_imagefield_widget_settings_validate($widget);
    case 'save':
      return pdf_to_imagefield_widget_settings_save($widget);
  }
}

/**
 * Implementation of CCK's hook_widget().
 */
function pdf_to_imagefield_widget(&$form, &$form_state, $field, $items, $delta = 0) {
  return filefield_widget($form, $form_state, $field, $items, $delta);
}

/**
 * Implementation of CCK's hook_default_value().
 */
function pdf_to_imagefield_default_value(&$form, &$form_state, $field, $delta) {
  return filefield_default_value($form, $form_state, $field, $delta);
}

/**
 * Convert pages from pdf file to ImageField files
 */
function pdf_to_imagefield_convert_pages($file, $path, $pdf) {
  $source = $pdf['filepath'];
  $result = $path . '/' . $pdf['fid'] . '.jpg';
  $density = '-density ' . $file->density_x . 'x' . $file->density_y;
  pdf_to_imagefield_convert_pdf($source, $result, array(), array(
    $density,
  ));
  $count = 0;
  $converted = array();
  while (file_exists($path . '/' . $pdf['fid'] . '-' . $count . '.jpg')) {
    $filename = $pdf['fid'] . '-' . $count . '.jpg';
    $converted[] = pdf_to_imagefield_save_image($filename, $path);
    $count++;
  }
  db_query('UPDATE {pdf_to_imagefield} SET finished = %d WHERE fid = %d', time(), $pdf['fid']);
  return $converted;
}

/**
 * Save created image to files table.
 */
function pdf_to_imagefield_save_image($filename, $path) {
  $image = new stdClass();
  $image->filename = $filename;
  $image->filepath = $path . '/' . $filename;
  $image->filemime = file_get_mimetype($image->filepath);
  $image->filesize = filesize($image->filepath);
  $image->status = 1;
  $image->timestamp = time();
  $image->uid = 1;
  drupal_write_record('files', $image);
  return $image;
}

/**
 * Check if field path is good to save file
 */
function pdf_to_imagefield_widget_file_path($field) {
  $path = filefield_widget_file_path($field);
  if (!file_check_directory($path, FILE_CREATE_DIRECTORY | FILE_MODIFY_PERMISSIONS, 'default_path')) {
    return FALSE;
  }
  return $path;
}

/**
 * Save converted images as ImageField files
 */
function pdf_to_imagefield_save_converted($images, $field, $pdf) {
  foreach (filefield_get_file_references($pdf) as $nid => $vid) {
    $node = node_load($nid);
    if (count($images)) {
      foreach ($images as $image) {

        #$image->list = FALSE;
        $node->{$field['field_name']}[] = (array) $image;
      }
      node_save($node);
      watchdog('pdf_to_imagefield', '%images pdf previews generated to %title node from %pdf file.', array(
        '%images' => count($images),
        '%title' => $node->title,
        '%pdf' => $pdf['filename'],
      ));
    }
    else {
      watchdog('pdf_to_imagefield', 'No pdf previews generated to %title node from %pdf file. But it is still in cron list.', array(
        '%title' => $node->title,
        '%pdf' => $pdf['filename'],
      ), WATCHDOG_ERROR);
    }
  }
}

/**
 * Menu callback. Administrator settings
 */
function pdf_to_imagefield_settings_form($form_state) {
  $form = array();
  $form['pdf_to_imagefield_convert_pdf'] = array(
    '#type' => 'textfield',
    '#title' => t('PDF file limit'),
    '#description' => t('Maximum number of pdf files to process per cron run.'),
    '#default_value' => variable_get('pdf_to_imagefield_convert_pdf', 1),
    '#size' => 6,
  );
  $form = system_settings_form($form);
  return $form;
}

/**
 * Convert function (depends on ImageAPI module)
 * This is almost a copy of _imageapi_imagemagick_convert() function, with 
 * that addition of $extra argument, used to pass parameters to convert *BEFORE* 
 * source file specification. 
 * Here it is needed to set density before rendering a PDF  
 */
function pdf_to_imagefield_convert_pdf($source, $dest, $args = array(), $extra = array()) {
  $d_arguments['quality'] = '-quality ' . escapeshellarg(variable_get('imageapi_imagemagick_quality', 75));

  // To make use of ImageMagick 6's parenthetical command grouping we need to make
  // the $source image the first parameter and $dest the last.
  // See http://www.imagemagick.org/Usage/basics/#cmdline for more info.
  $command = implode(' ', $extra) . ' ' . escapeshellarg($source) . ' ' . implode(' ', $args) . ' ' . escapeshellarg($dest);
  if (0 != _imageapi_imagemagick_convert_exec($command, $output, $errors)) {
    $errors_txt = '<pre>' . (is_array($errors) ? implode("\n", $errors) : $errors) . '</pre>';
    watchdog('pdf to image: imageapi imagemagick', '!errors', array(
      '!errors' => $errors_txt,
    ), WATCHDOG_ERROR);
    return FALSE;
  }
  return file_exists($dest);
}

/**
 * Widget previews theme
 */
function theme_pdf_to_imagefield_widget_preview($file) {

  // Remove the current description so that we get the filename as the link.
  if (isset($file['data']['description'])) {
    unset($file['data']['description']);
  }

  // get finished date or zero if not
  $finished = db_result(db_query_range('SELECT finished FROM {pdf_to_imagefield} WHERE fid = %d', $file['fid'], 0, 1));

  // define status text
  $status = $finished ? t('Page previews generated at %date', array(
    '%date' => format_date($finished, 'custom', 'Y.m.d H:i'),
  )) : t('Page previews generation not completed. Waiting in queue.');

  // return output
  return '<div class="filefield-file-info">' . '<div class="filename">' . theme('filefield_file', $file) . '</div>' . '<div class="filesize">' . format_size($file['filesize']) . '</div>' . '<div class="filemime">' . $file['filemime'] . '</div>' . '<div class="pdfstatus"><small>' . $status . '</small></div>' . '</div>';
}

/**
 * Implementation of hook_file_insert().
 *
 * Add file to table
 */
function pdf_to_imagefield_file_insert($file) {
  if (pdf_to_imagefield_check_file($file)) {
    $pdf = new stdClass();
    $pdf->fid = $file->fid;
    $pdf->field = $file->field['widget']['target_imagefield'];
    $pdf->count = 0;
    $pdf->density_x = preg_replace('/^([0-9]+)x[0-9]+$/', '\\1', $file->field['widget']['density']);
    $pdf->density_y = preg_replace('/^[0-9]+x([0-9]+)$/', '\\1', $file->field['widget']['density']);
    $pdf->finished = 0;
    drupal_write_record('pdf_to_imagefield', $pdf);
  }
}

/**
 * Implementation of hook_file_delete().
 *
 * Delete file from table
 */
function pdf_to_imagefield_file_delete($file) {
  db_query('DELETE FROM {pdf_to_imagefield} WHERE fid = %d', $file->fid);
}

/**
 * Helper funtion to check if file is good to convert pages
 */
function pdf_to_imagefield_check_file($file) {

  // check if variables are in place
  if (!isset($file->field['widget']['module']) && !isset($file->field['widget']['target_imagefield']) && !isset($file->field['multiple'])) {
    return FALSE;
  }

  // check if variables are good
  if ($file->field['widget']['module'] != 'pdf_to_imagefield' && $file->field['widget']['target_imagefield'] == 0 && $file->field['multiple'] == 1) {
    return FALSE;
  }

  // return TRUE if TRUE
  return TRUE;
}

/**
 * @file
 * PDF to ImageField widget hooks and callbacks.
 */

/**
 * Implementation of CCK's hook_widget_settings($op = 'form').
 */
function pdf_to_imagefield_widget_settings_form($widget) {
  if (!pdf_to_imagefield_check_imagemagick($widget)) {
    drupal_set_message(t('ImageMagick test pdf to image conversion failed. Please check your system ImageMagick and/or Ghostscript configuration. While you seeing this message, pdf files will be queued and stay unprocessed.'), 'error');
  }

  // get standart settings from filefield
  $form = module_invoke('filefield', 'widget_settings', 'form', $widget);

  // set & lock pdf extension from modification
  $form['file_extensions']['#default_value'] = 'pdf';
  $form['file_extensions']['#disabled'] = TRUE;

  // create list of options to target form
  $imagefields = array();
  $filefields = filefield_get_field_list(arg(3));
  foreach ($filefields as $key => $filefield) {
    if ($filefield['widget']['module'] == 'imagefield' && $filefield['multiple'] == 1) {
      $imagefields[$key] = $filefield['widget']['label'] . ' (' . $filefield['field_name'] . ')';
    }
  }

  // just 4fun
  $imagefields[0] = count($imagefields) ? t('No ImageField selected') : t('No ImageField found');

  // target form
  $form['target_imagefield'] = array(
    '#type' => 'select',
    '#title' => t('Target ImageField'),
    '#options' => $imagefields,
    '#default_value' => !empty($widget['target_imagefield']) ? $widget['target_imagefield'] : 0,
    '#description' => t('Choose an ImageField where should be stored extracted pages. ImageField must be assigned to the same node type and should allow to upload multiple images.'),
  );
  $form['density'] = array(
    '#type' => 'textfield',
    '#title' => t('Density used for rendering PDF'),
    '#default_value' => !empty($widget['density']) ? $widget['density'] : '100x100',
    '#size' => 15,
    '#maxlength' => 10,
    '#description' => t('Horizontal and vertical density of the image XxY (e.g. 120x120). Default is 100x100.'),
  );
  return $form;
}

/**
 * Implementation of CCK's hook_widget_settings($op = 'validate').
 */
function pdf_to_imagefield_widget_settings_validate($widget) {

  // Check that set density is valid.
  if (!empty($widget['density']) && !preg_match('/^[0-9]+x[0-9]+$/', $widget['density'])) {
    form_set_error('density', t('Please specify a density in the format XxY (e.g. 120x120).'));
  }
}

/**
 * Implementation of CCK's hook_widget_settings($op = 'save').
 */
function pdf_to_imagefield_widget_settings_save($widget) {
  $filefield_settings = module_invoke('filefield', 'widget_settings', 'save', $widget);
  return array_merge($filefield_settings, array(
    'target_imagefield',
    'density',
  ));
}

/**
 * FormAPI theme function. Theme the output of an pdf field.
 */
function theme_pdf_to_imagefield_widget($element) {
  $element['#id'] .= '-upload';

  // Link the label to the upload field.
  return theme('form_element', $element, $element['#children']);
}

/**
 * Helper function to check if ImageMagick is ready to convert
 */
function pdf_to_imagefield_check_imagemagick($widget) {

  // init test varaibles
  $source = drupal_get_path('module', 'pdf_to_imagefield') . '/imagemagick_test.pdf';
  $result = file_directory_path() . '/imagemagick_test.jpg';
  $density = !empty($widget['density']) ? $widget['density'] : '100x100';

  // check conversion
  if (pdf_to_imagefield_convert_pdf($source, $result, array(), array(
    '-density ' . $density,
  ))) {
    file_delete($result);
    return TRUE;
  }
  return FALSE;
}

/**
 * Element #process callback function.
 */
function pdf_to_imagefield_widget_process($element, $edit, &$form_state, $form) {
  $file = $element['#value'];
  if (isset($element['preview']) && $file['fid'] != 0) {
    $element['preview']['#value'] = theme('pdf_to_imagefield_widget_preview', $file);
  }
  return $element;
}

Functions

Namesort descending Description
pdf_to_imagefield_check_file Helper funtion to check if file is good to convert pages
pdf_to_imagefield_check_imagemagick Helper function to check if ImageMagick is ready to convert
pdf_to_imagefield_convert_pages Convert pages from pdf file to ImageField files
pdf_to_imagefield_convert_pdf Convert function (depends on ImageAPI module) This is almost a copy of _imageapi_imagemagick_convert() function, with that addition of $extra argument, used to pass parameters to convert *BEFORE* source file specification. Here it is needed to set…
pdf_to_imagefield_cron Implementation of hook_cron().
pdf_to_imagefield_default_value Implementation of CCK's hook_default_value().
pdf_to_imagefield_elements Implementation of hook_elements().
pdf_to_imagefield_file_delete Implementation of hook_file_delete().
pdf_to_imagefield_file_insert Implementation of hook_file_insert().
pdf_to_imagefield_menu Implementation of hook_menu().
pdf_to_imagefield_save_converted Save converted images as ImageField files
pdf_to_imagefield_save_image Save created image to files table.
pdf_to_imagefield_settings_form Menu callback. Administrator settings
pdf_to_imagefield_theme Implementation of hook_theme().
pdf_to_imagefield_widget Implementation of CCK's hook_widget().
pdf_to_imagefield_widget_file_path Check if field path is good to save file
pdf_to_imagefield_widget_info Implementation of CCK's hook_widget_info().
pdf_to_imagefield_widget_process Element #process callback function.
pdf_to_imagefield_widget_settings Implementation of CCK's hook_widget_settings().
pdf_to_imagefield_widget_settings_form Implementation of CCK's hook_widget_settings($op = 'form').
pdf_to_imagefield_widget_settings_save Implementation of CCK's hook_widget_settings($op = 'save').
pdf_to_imagefield_widget_settings_validate Implementation of CCK's hook_widget_settings($op = 'validate').
theme_pdf_to_imagefield_widget FormAPI theme function. Theme the output of an pdf field.
theme_pdf_to_imagefield_widget_preview Widget previews theme