<?php
/*******************************************************************************
* PHP Paypal IPN Integration Class
*******************************************************************************
* Author: Micah Carrick
* Email: [email protected] * Website: http://www.micahcarrick.com
*
* File: paypal.class.php
* Version: 1.0.0
* Copyright: (c) 2005 - Micah Carrick
* You are free to use, distribute, and modify this software
* under the terms of the GNU General Public License. See the
* included license.txt file.
*
*******************************************************************************
* VERION HISTORY:
*
* v1.0.0 [04.16.2005] - Initial Version
*
*******************************************************************************
* DESCRIPTION:
*
* This file provides a neat and simple method to interface with paypal and
* The paypal Instant Payment Notification (IPN) interface. This file is
* NOT intended to make the paypal integration "plug 'n' play". It still
* requires the developer (that should be you) to understand the paypal
* process and know the variables you want/need to pass to paypal to
* achieve what you want.
*
* This class handles the submission of an order to paypal aswell as the
* processing an Instant Payment Notification.
*
* This code is based on that of the php-toolkit from paypal. I've taken
* the basic principals and put it in to a class so that it is a little
* easier--at least for me--to use. The php-toolkit can be downloaded from
* http://sourceforge.net/projects/paypal.
*
* To submit an order to paypal, have your order form POST to a file with:
*
* $p = new paypal_class;
* $p->add_field('business', '[email protected]');
* $p->add_field('first_name', $_POST['first_name']);
* ... (add all your fields in the same manor)
* $p->submit_paypal_post();
*
* To process an IPN, have your IPN processing file contain:
*
* $p = new paypal_class;
* if ($p->validate_ipn()) {
* ... (IPN is verified. Details are in the ipn_data() array)
* }
*
*
* In case you are new to paypal, here is some information to help you:
*
* 1. Download and read the Merchant User Manual and Integration Guide from
* http://www.paypal.com/en_US/pdf/integration_guide.pdf. This gives
* you all the information you need including the fields you can pass to
* paypal (using add_field() with this class) aswell as all the fields
* that are returned in an IPN post (stored in the ipn_data() array in
* this class). It also diagrams the entire transaction process.
*
* 2. Create a "sandbox" account for a buyer and a seller. This is just
* a test account(s) that allow you to test your site from both the
* seller and buyer perspective. The instructions for this is available
* at https://developer.paypal.com/ as well as a great forum where you
* can ask all your paypal integration questions. Make sure you follow
* all the directions in setting up a sandbox test environment, including
* the addition of fake bank accounts and credit cards.
*
*******************************************************************************
*/
class paypal_class {
var $last_error; // holds the last error encountered
var $ipn_log; // bool: log IPN results to text file?
var $ipn_log_file; // filename of the IPN log
var $ipn_response; // holds the IPN response from paypal
var $ipn_data = array(); // array contains the POST values for IPN
var $fields = array(); // array holds the fields to submit to paypal
function paypal_class() {
// initialization constructor. Called when class is created.
// populate $fields array with a few default values. See the paypal
// documentation for a list of fields and their data types. These defaul
// values can be overwritten by the calling script.
$this->add_field('rm','2'); // Return method = POST
$this->add_field('cmd','_xclick');
}
function add_field($field, $value) {
// adds a key=>value pair to the fields array, which is what will be
// sent to paypal as POST variables. If the value is already in the
// array, it will be overwritten.
$this->fields["$field"] = $value;
}
function submit_paypal_post() {
// this function actually generates an entire HTML page consisting of
// a form with hidden elements which is submitted to paypal via the
// BODY element's onLoad attribute. We do this so that you can validate
// any POST vars from you custom form before submitting to paypal. So
// basically, you'll have your own form which is submitted to your script
// to validate the data, which in turn calls this function to create
// another hidden form and submit to paypal.
// The user will briefly see a message on the screen that reads:
// "Please wait, your order is being processed..." and then immediately
// is redirected to paypal.
echo "<html>\n";
echo "<head><title>Processing Payment...</title></head>\n";
echo "<body onLoad=\"document.form.submit();\">\n";
echo "<center><h3>Please wait, your order is being processed...</h3></center>\n";
echo "<form method=\"post\" name=\"form\" action=\"".$this->paypal_url."\">\n";
// parse the paypal URL
$url_parsed=parse_url($this->paypal_url);
// generate the post string from the _POST vars aswell as load the
// _POST vars into an arry so we can play with them from the calling
// script.
$post_string = '';
foreach ($_POST as $field=>$value) {
$this->ipn_data["$field"] = $value;
$post_string .= $field.'='.urlencode($value).'&';
}
$post_string.="cmd=_notify-validate"; // append ipn command
// open the connection to paypal
$fp = fsockopen($url_parsed[host],"80",$err_num,$err_str,30);
if(!$fp) {
// could not open the connection. If loggin is on, the error message
// will be in the log.
$this->last_error = "fsockopen error no. $errnum: $errstr";
$this->log_ipn_results(false);
return false;
} else {
// Post the data back to paypal
fputs($fp, "POST $url_parsed[path] HTTP/1.1\r\n");
fputs($fp, "Host: $url_parsed[host]\r\n");
fputs($fp, "Content-type: application/x-www-form-urlencoded\r\n");
fputs($fp, "Content-length: ".strlen($post_string)."\r\n");
fputs($fp, "Connection: close\r\n\r\n");
fputs($fp, $post_string . "\r\n\r\n");
// loop through the response from the server and append to variable
while(!feof($fp)) {
$this->ipn_response .= fgets($fp, 1024);
}
// Success or failure being logged?
if ($success) $text .= "SUCCESS!\n";
else $text .= 'FAIL: '.$this->last_error."\n";
// Log the POST variables
$text .= "IPN POST Vars from Paypal:\n";
foreach ($this->ipn_data as $key=>$value) {
$text .= "$key=$value, ";
}
// Log the response from the paypal server
$text .= "\nIPN Response from Paypal Server:\n ".$this->ipn_response;
// Write to log
$fp=fopen($this->ipn_log_file,'a');
fwrite($fp, $text . "\n\n");
fclose($fp); // close file
}
function dump_fields() {
// Used for debugging, this function will output all the field/value pairs
// that are currently defined in the instance of the class using the
// add_field() function.
