How to modify this script to allow URL POSTing with PHP - php

Question

This is an experiment for a proof of concept. I created a VPS where I have a simple upload form and PHP form processor script. The point of this is to test an iOS and Android app we are developing. This question is not about security or efficiency (yet), just functionality. I need to modify the PHP below to receive an image using POST without the aid of an HTML FORM. We are currently POSTing to Dropbox and Google Drive no problem. We are now looking into what it would take to store images on our own servers, we just need to formulate a proof of concept to receive this image with PHP that was submitted with POST.
With that out of the way; I want to send an image to a server from a mobile device over the only upload method available without additional libraries - HTTP. Using FTP or SSH requires additional code and we're trying to keep it light. So I was going to send an image with HTTP POST which I am pulling off with an HTML FORM currently. However, I need to formulate a POST that sends only an image - no other variables. This is my current HTML form:
<!-- The data encoding type, enctype, MUST be specified as below -->
<form enctype="multipart/form-data" action="__URL__" method="POST">
<!-- MAX_FILE_SIZE must precede the file input field -->
<input type="hidden" name="MAX_FILE_SIZE" value="30000" />
<!-- Name of input element determines name in $_FILES array -->
Send this file: <input name="userfile" type="file" />
<input type="submit" value="Send File" />
</form>
This is my processor PHP:
<?php
// In PHP versions earlier than 4.1.0, $HTTP_POST_FILES should be used instead
// of $_FILES.
$uploaddir = '/var/www/uploads/';
$uploadfile = $uploaddir . basename($_FILES['userfile']['name']);
echo '<pre>';
if (move_uploaded_file($_FILES['userfile']['tmp_name'], $uploadfile)) {
echo "File is valid, and was successfully uploaded.\n";
} else {
echo "Potential error.\n";
}
echo 'Here is some more debugging info:';
print_r($_FILES);
print "</pre>";
?>
Works perfectly over a browser, no problems. Now I need to modify the PHP portion to allow a POST over URL - essentially dropping the use of an HTML form. It would be great to distinguish the files uploaded by using the name of the file I am sending or I can provide that variable from my app. Any guidance would be appreciated.
Reference: http://php.net/manual/en/features.file-upload.post-method.php

Answer 1

You don't need to modify your PHP. Just send file from your iOS/Android application as if it was sent by the form, i.e. using multipart/form-data encoding.
Or if you want to send it another way, explain how exactly you want it sent, there is no another standard way to send files "POST over URL".