Features

Inline conversion of existing files

Existing managed files can be converted while editing the containing node.

Automatic conversion of uploaded files

Manage fields page of a content type. Showing a new file field using the Convert File widget:

Convert File widget exposes two new configuration elements to the field settings:

Field formatters

Display the current converted file, as well as all backups of previous versions.

Configuration:

Display (this file was uploaded as .txt, auto converted to .odt, then later via inline conversion form to .pdf):

File conversion is based on rules

While editing the reaction rule "CF Google Drive convert to PDF"

Code may also provide file conversion by calling the following function convertfile_convert_file(), though rules still provide the ultimate functionality.

/**
 * Programmatic wrapper for convertfile_validate_conversion().
 *
 * Call this function directly to perform a programmatically based conversion.
 *
 * @param int|stdClass $file
 *   The FID or file object to convert. This object may be modified.
 * @param string $provider
 *   The machine name of the provider.
 * @param string $format
 *   The machine name of the format to convert to.
 *
 * @return bool
 *   TRUE on successful conversion, FALSE otherwise. See watchdog for error
 *   details.
 */
function convertfile_convert_file($file, $provider, $format, $extensions = NULL) {
  $report = FALSE;

  $file = (is_object($file)) ? $file : file_load($file);
  if ($file) {
    $instance = array(
      'widget' => array(
        'settings' => array(
          'convertfile_provider' => $provider,
          'convertfile_format' => $format,
          'convertfile_extensions' => $extensions,
        ),
      ),
    );
    $result = convertfile_validate_conversion($file, $instance);
    if (is_array($result) && empty($result)) {
      $report = TRUE;
    }
  }

  return $report;
}

File conversion done inside validators

Any failed conversion happening during an upload will fail the entire upload via validation form errors.