e-mail processing script features:
- Saves the e-mail sender, subject and body to a database
- Saves any attachments as files and creates an entry for those files in the database, associated with the e-mail info in #1
- Sends a response back to the sender telling them what files were received and their file sizes
- Checks a list of allowed senders to make sure we only take files from specified addresses.
database setup:
If you’re going to use the database features, you’ll need a database. Here’s the SQL to create an identical setup to the one I have:
-- Here's my DB structure
SET SQL_MODE="NO_AUTO_VALUE_ON_ZERO";
-- Table structure for table `emails`
CREATE TABLE IF NOT EXISTS `emails` (
`id` int(100) NOT NULL AUTO_INCREMENT,
`from` varchar(250) NOT NULL,
`subject` text NOT NULL,
`body` text NOT NULL,
`date` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP,
PRIMARY KEY (`id`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1;
-- --------------------------------------------------------
-- Table structure for table `files`
CREATE TABLE IF NOT EXISTS `files` (
`id` int(100) NOT NULL AUTO_INCREMENT,
`email_id` int(100) NOT NULL,
`filename` varchar(255) NOT NULL,
`size` varchar(100) NOT NULL,
PRIMARY KEY (`id`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1;
Pretty straightforward I would say. The size field in the files table stores a user friendly “100Mb” type description of the size. You will need to know your database name, username, password and host name in the next step.
the email handling script:
The max_time_limit variable is how long you want the script to be allowed to run. The default max for your server might be too small to handle 20Mb of attachments (the max you can send with Google).
#!/usr/bin/php -q
<?php
// Use -q so that php doesn't print out the HTTP headers
// Anything printed to STDOUT will be sent back to the sender as an error!
// Config options
$max_time_limit = 600; // in seconds
// A safe place for files with trailing slash (malicious users could upload a php or executable file!)
$save_directory = "/some/folder/path";
$allowedSenders = Array('myemail@gmail.com',
'Bob the Builder <example@gmail.com>'); // only people you trust!
$send_email = TRUE; // Send confirmation e-mail?
$save_msg_to_db = TRUE; // Save e-mail body to DB?
$db_host = 'localhost';
$db_un = 'db_un';
$db_pass = 'password';
$db_name = 'db_name';
// ------------------------------------------------------
set_time_limit($max_time_limit);
ini_set('max_execution_time',$max_time_limit);
global $from, $subject, $boundary, $message, $save_path,$files_uploaded;
$save_path = $save_directory;
$files_uploaded = Array();
function formatBytes(&$bytes, $precision = 2) {
$units = array('B', 'KB', 'MB', 'GB', 'TB');
$bytes = max($bytes, 0);
$pow = floor(($bytes ? log($bytes) : 0) / log(1024));
$pow = min($pow, count($units) - 1);
$bytes /= pow(1024, $pow);
return round($bytes, $precision) . ' ' . $units[$pow];
}
function process_part(&$email_part){
global $message;
// Max two parts. The data could have more than one \n\n in it somewhere,
// but the first \n\n should be after the content info block
$parts = explode("\n\n",$email_part,2);
$info = split("\n",$parts[0]);
$type;
$name;
$encoding;
foreach($info as $line){
if(preg_match("/Content-Type: (.*);/",$line,$matches)){
$type = $matches[1];
}
if(preg_match("/Content-Disposition: attachment; filename=\"(.*)\"/",
$line,$matches)){
$name = time() . "_" . $matches[1];
}
if(preg_match("/Content-Transfer-Encoding: (.*)/",$line,$matches)){
$encoding = $matches[1];
}
}
// We don't know what it is, so we don't know how to process it
if(!isset($type)){ return FALSE; }
switch($type){
case 'text/plain':
// "But if you get a text attachment, you're going to overwrite
// the real message!" Yes. I don't care in this case...
$message = $parts[1];
break;
case 'multipart/alternative':
// Multipart comes where the client sends the data in two formats so
// that recipients who can't read (or don't like) fancy content
// have another way to read it. Eg. When sending an html formatted
// message, they will also send a plain text message
process_multipart($info,$parts[1]);
break;
default:
if(isset($name)){ // the main message will not have a file name...
// text/html messages won't be saved!
process_data($name,$encoding,$parts[1]);
}elseif(!isset($message) && strpos($type,'text') !== FALSE){
$message = $parts[1]; // Going out on a limb here...capture
// the message
}
break;
}
}
function process_multipart(&$info,&$data){
global $message;
$bounds;
foreach($info as $line){
if (preg_match("/boundary=(.*)$/",$line,$matches)){
$bounds = $matches[1];
}
}
$multi_parts = split("--" .$bounds,$data);
for($i = 1;$i < count($multi_parts);$i++){
process_part($multi_parts[$i]);
}
}
function process_data(&$name,&$encoding = 'base64' ,&$data){
global $save_path,$files_uploaded;
// find a filename that's not in use. There's a race condition
// here which should be handled with flock or something instead
// of just checking for a free filename
$unlocked_and_unique = FALSE;
while(!$unlocked_and_unique){
// Find unique
$name = time() . "_" . $name;
while(file_exists($save_path . $name)) {
$name = time() . "_" . $name;
}
// Attempt to lock
$outfile = fopen($save_path.$name,'w');
if(flock($outfile,LOCK_EX)){
$unlocked_and_unique = TRUE;
}else{
flock($outfile,LOCK_UN);
fclose($outfile);
}
}
if($encoding == 'base64'){
fwrite($outfile,base64_decode($data));
}elseif($encoding == 'uuencode'){
// I haven't actually seen this in an e-mail, but older clients may
// still use it...not 100% sure that this will work correctly as is
fwrite($outfile,convert_uudecode($data));
}
flock($outfile,LOCK_UN);
fclose($outfile);
// This is for readability for the return e-mail and in the DB
$files_uploaded[$name] = formatBytes(filesize($save_path.$name));
}
// Process the e-mail from stdin
$fd = fopen('php://stdin','r');
$email = '';
while(!feof($fd)){ $email .= fread($fd,1024); }
// Headers hsould go till the first \n\n. Grab everything before that, then
// split on \n and process each line
$headers = split("\n",array_shift(explode("\n\n",$email,2)));
foreach($headers as $line){
// The only 3 headers we care about...
if (preg_match("/^Subject: (.*)/", $line, $matches)) {
$subject = $matches[1];
}
if (preg_match("/^From: (.*)/", $line, $matches)) {
$from = $matches[1];
}
if (preg_match("/boundary=(.*)$/",$line,$matches)){
$boundary = $matches[1];
}
}
// Check $from here and exit if it's blank or
// not someone you want to get mail from!
if(!in_array($from,$allowedSenders)){
die("Not an allowed sender");
}
// No boundary was in the e-mail sent to us. We don't know what to do!
if(!isset($boundary)){
die("I couldn't find an e-mail boundary. Maybe this isn't an e-mail");
}
// Split the e-mail on the found boundary
// The first part will be the header (hence $i = 1 in our loop)
// Each other chunk should have some info on the chunk,
// then \n\n then the chunk data
// Process each chunk
$email_parts = split("--" . $boundary,$email);
for($i = 1;$i < count($email_parts);$i++){
process_part($email_parts[$i]);
}
// Put the results in the database if needed
if($save_msg_to_db){
mysql_connect($db_host,$db_un,$db_pass);
mysql_select_db($db_name);
$q = "INSERT INTO `emails` (`from`,`subject`,`body`) VALUES ('" .
mysql_real_escape_string($from) . "','" .
mysql_real_escape_string($subject) . "','" .
mysql_real_escape_string($message) . "')";
mysql_query($q) or die(mysql_error());
if(count($files_uploaded) > 0){
$id = mysql_insert_id();
$q = "INSERT INTO `files` (`email_id`,`filename`,`size`) VALUES ";
$filesar = Array();
foreach($files_uploaded as $f => $s){
$filesar[] = "('$id','" .
mysql_real_escape_string($f) . "','" .
mysql_real_escape_string($s) . "')";
}
$q .= implode(', ',$filesar);
mysql_query($q) or die(mysql_error());
}
}
// Send response e-mail if needed
if($send_email && $from != ""){
$to = $from;
$newmsg = "Thanks! I just uploaded the following ";
$newmsg .= "files to your storage:\n\n";
$newmsg .= "Filename -- Size\n";
foreach($files_uploaded as $f => $s){
$newmsg .= "$f -- $s\n";
}
$newmsg .= "\nI hope everything looks right. If not,";
$newmsg .= "please send me an e-mail!\n";
mail($to,$subject,$newmsg);
}
testing the script:
Save an e-mail, headers and all, and upload it to your server. Cat the saved e-mail to your script to test it.
cat 'saved_email.txt' | ./process_email.php
You should get an e-mail response, see new entries in your DB and see your saved attachments. If you don’t, you can print debugging statements or use your usual PHP debugging techniques with this easy testing method.
Enjoy!
