PHP doesn't seem to be processing script to post to MySQL - php

Question

I'm using html5 canvas to capture a signature and store it in MySQL. I've got everything in the script working except for the part that saves the signature and sends it to MySQL.
My knowledge of AJAX is none so I'm working off what I read in books, see on tutorials and get help on from here.
So in Firefox console when I click on save signature I can see the script displays the post.php file it's supposed to go to and displays a 200 ok notification but nothing happens, it doesn't post in MySQL (which doesn't surprise me as I'm sure my code is incorrect) and I don't see any errors.
What I want to accomplish is to upload the signature image to a folder on the server and save the path to the image in MySQL. Being unfamiliar with JavaScript, Jquery and Ajax I'm confused with how to get this to function.
Here is the jquery:
$(document).ready(function () {
/** Set Canvas Size **/
var canvasWidth = 400;
var canvasHeight = 75;
/** IE SUPPORT **/
var canvasDiv = document.getElementById('signaturePad');
canvas = document.createElement('canvas');
canvas.setAttribute('width', canvasWidth);
canvas.setAttribute('height', canvasHeight);
canvas.setAttribute('id', 'canvas');
canvasDiv.appendChild(canvas);
if (typeof G_vmlCanvasManager != 'undefined') {
canvas = G_vmlCanvasManager.initElement(canvas);
}
var context = canvas.getContext("2d");
var clickX = new Array();
var clickY = new Array();
var clickDrag = new Array();
var paint;
/** Redraw the Canvas **/
function redraw() {
canvas.width = canvas.width; // Clears the canvas
context.strokeStyle = "#000000";
context.lineJoin = "miter";
context.lineWidth = 2;
for (var i = 0; i < clickX.length; i++) {
context.beginPath();
if (clickDrag[i] && i) {
context.moveTo(clickX[i - 1], clickY[i - 1]);
} else {
context.moveTo(clickX[i] - 1, clickY[i]);
}
context.lineTo(clickX[i], clickY[i]);
context.closePath();
context.stroke();
}
}
/** Save Canvas **/
$("#saveSig").click(function saveSig() {
//encode URI
var sigData = encodeURIComponent(canvas.toDataURL("image/png"));
$("#imgData").html('Thank you! Your signature was saved');
var ajax = XMLHttpRequest();
ajax.open("POST", 'post.php');
ajax.setRequestHeader('Content-Type', 'application/upload');
ajax.send(sigData);
// $('#debug').html(sigData);
});
/** Clear Canvas **/
$('#clearSig').click(
function clearSig() {
clickX = new Array();
clickY = new Array();
clickDrag = new Array();
context.clearRect(0, 0, canvas.width, canvas.height);
});
/**Draw when moving over Canvas **/
$('#signaturePad').mousemove(function (e) {
if (paint) {
addClick(e.pageX - this.offsetLeft, e.pageY - this.offsetTop, true);
redraw();
}
});
/**Stop Drawing on Mouseup **/
$('#signaturePad').mouseup(function (e) {
paint = false;
});
/** Starting a Click **/
function addClick(x, y, dragging) {
clickX.push(x);
clickY.push(y);
clickDrag.push(dragging);
}
$('#signaturePad').mousedown(function (e) {
var mouseX = e.pageX - this.offsetLeft;
var mouseY = e.pageY - this.offsetTop;
paint = true;
addClick(e.pageX - this.offsetLeft, e.pageY - this.offsetTop);
redraw();
});
});
and here is the PHP: Also I didn't write the php code below it's part of the entire signature pad so I'm sure it's not correct.
<?php
session_start();
if (isset($GLOBALS["HTTP_RAW_POST_DATA"]))
{
$session_id = $_SERVER['REMOTE_ADDR'];
// Get the data
$imageData=$GLOBALS['HTTP_RAW_POST_DATA'];
// Remove the headers (data:,) part.
// A real application should use them according to needs such as to check image type
$filteredData=substr($imageData, strpos($imageData, ",")+1);
// Need to decode before saving since the data we received is already base64 encoded
$unencodedData=base64_decode($filteredData);
//echo "unencodedData".$unencodedData;
$imageName = "sign_" . rand(5,1000) . rand(1, 10) . rand(10000, 150000) . rand(1500, 100000000) . ".png";
//Set the absolute path to your folder (i.e. /usr/home/your-domain/your-folder/
$filepath = "xampp/htdocs/alpha/site7/images/" . $imageName;
$fp = fopen("$filepath", 'wb' );
fwrite( $fp, $unencodedData);
fclose( $fp );
//Connect to a mySQL database and store the user's information so you can link to it later
$link = mysql_connect('localhost','root', 'password') OR DIE(mysql_error);
mysql_select_db("customer", $link);
mysql_query("INSERT INTO 'signature' ('session', 'image_location') VALUES ('$session_id', '$imageName')") OR DIE(mysql_error());
mysql_close($link);
}
?>
And the html:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta content="text/html; charset=utf-8" http-equiv="Content-Type" />
<title>Signature Pad</title>
<!-- The Signature Pad -->
<script type ="text/javascript" src="jquery.min.js"></script>
<script type="text/javascript" src="signature-pad.js"></script>
</head>
<body>
<center>
<fieldset style="width: 435px">
<br/>
<br/>
<div id="signaturePad" style="border: 1px solid #ccc; height: 55px; width: 400px;"></div>
<br/>
<button id="clearSig" type="button">Clear Signature</button>
<button id="saveSig" type="button">Save Signature</button>
<div id="imgData"></div>
<div
<br/>
<br/>
</fieldset>
</center>
<div id="debug"></div>
</body>
</html>
After some head beating over this I've finally been able to discover some errors.
After signing the signature pad and pressing the save signature button I get these errors in Firebug
Warning: fopen(xampp/htdocs/alpha/site6/images/sign_42281643871777767.png): failed to open stream: No such file or directory in C:\xampp\htdocs\alpha\site6\post.php on line 20
Warning: fwrite() expects parameter 1 to be resource, boolean given in C:\xampp\htdocs\alpha\site6\post.php on line 21
Warning: fclose() expects parameter 1 to be resource, boolean given in C:\xampp\htdocs\alpha\site6\post.php on line 22
You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ''signatures' ('session', 'image_location') VALUES ('127.0.0.1', 'sign_42281643871' at line 1
Since I don't have any knowledge of Jquery or Ajax and how they are creating the image and attempting to post it to a folder I'm pretty much stuck at this point!

Answer 1

seems I'm answering my own problems, I've figured out what the fopen errors were, I wasn't using an absolute path so adding a / before the start of the path cleared up everything except for the last error of this:
You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ''signature' ('session', 'image_location') VALUES ('127.0.0.1', 'sign_11814198867' at line 1