You can do it with the wpcf7_mail_components filter.
Thanks for the tip. In order to make this useful, i had to use some reflection.
<?php
/** file wp-content/mu-plugins/cf7-extended-files.php **/
// allow non-file fields as attachment; best use with pipes!!
add_filter(@wpcf7_mail_components,function($comp){
// read private and protected properties from object
$getProp = function($object,$property) {
$reflect = new ReflectionProperty(get_class($object), $property);
$reflect->setAccessible(true);
return $reflect->getValue($object);
};
// attachments in template
$tplAttach = $getProp(WPCF7_Mail::get_current(),@template)[@attachments];
// read real file tags, these will be skipped later
$fileTags= array_map(function($item){
// mapping creates the search strings
return '['.$item[@name].']';
},array_filter($getProp(WPCF7_ContactForm::get_current(),@scanned_form_tags),function($item){
// match all file-tags
return $item[@basetype]==@file;
}));
// remove the file-tags from template; remaining static files and non-file-tags
$toAttach = str_replace($fileTags,'',$tplAttach);
// search all remaining tags $attachMatch['names'] contains these without brackets
preg_match_all('/\[(?P<name>[a-z0-9_\-]+)\]/i',$toAttach,$attachMatch);
// merge form data and remaining tags into values
$data = WPCF7_Submission::get_instance()->get_posted_data();
$toAttach = array_intersect_key($data,array_flip($attachMatch[@name]));
// for security only allow the files to be placed in wp_uploads of the current site
$uploadDir = wp_upload_dir()[@basedir];
// fetch current attachments by reference to extend
$mailAttach = &$comp[@attachments];
foreach($toAttach as $path) {
$path[0]=='/' || $path=realpath(implode('/',[$uploadDir,$path]));
if(strpos($uploadDir,$path)===0&&is_file($path)&&is_readable($path)) { // check for existence and readability
$mailAttach[] = $path;
}
}
//file_put_contents('/tmp/cf7-'.time(),print_r([$toAttach,$mailAttach,$comp],1));
return $comp;
});
the easiest solution would have been a hook where non-uploaded files are skipped in includes/mail.php:114 WPCF7_Mail::attachments
