Generate png-file with php from dataURI sent through ajax

Question

I have an svg file that is generating a dataURI-png and that works great. And I want that dataURI to be saved as an image, therefore I try to send the dataURI through ajax t

Answer 1

$dataUrl = $_REQUEST['datauri'];
$id = $_REQUEST['id'];

list($meta, $content) = explode(',', $dataUrl);

$content = str_replace(".", "", $content); // some android browsers will return a data64 that may not be accurate without this without this.

$content = base64_decode($content);
$image = imagecreatefromstring($content);

imagepng($image, './tmp-png/'.$id.'.png', 90); // Third parameter is optional. Just placed it incase you want to save storage space...

Answer 2

You can use canvas.toBlob(), send image to php as a Blob, use php://input to read Blob at php , see Beyond $_POST, $_GET and $_FILE: Working with Blob in JavaScript and PHP

javascript

if (!HTMLCanvasElement.prototype.toBlob) {
 Object.defineProperty(HTMLCanvasElement.prototype, "toBlob", {
  value: function (callback, type, quality) {

    var binStr = atob( this.toDataURL(type, quality).split(",")[1] ),
        len = binStr.length,
        arr = new Uint8Array(len);

    for (var i=0; i<len; i++ ) {
     arr[i] = binStr.charCodeAt(i);
    }

    callback( new Blob( [arr], {type: type || "image/png"} ) );
  }
 });
}

can.toBlob(function(blob) {
  var request = new XMLHttpRequest();
  // to receive `echo`ed file from `php` as `Blob`
  // request.responseType = "blob";
  request.open("POST", "readBlobInput.php", true);
  request.setRequestHeader("x-file-name", "filename");
  request.onload = function() {
    // `this.response` : `Blob` `echo`ed from `php`
    // console.log(this.response)
    console.log(this.responseText);
  }
  request.send(blob)
});

readBlobInput.php

<?php
// the Blob will be in the input stream, so we use php://input
$input = file_get_contents("php://input");
// choose a filename, use request header
$tmpFilename = $_SERVER["HTTP_X_FILE_NAME"];
// http://stackoverflow.com/q/541430/
$folder = __DIR__ . "/tmp-png"; 
// http://stackoverflow.com/q/17213403/
is_dir($folder) || @mkdir($folder) || die("Can't Create folder");
// put contents of file in folder
file_put_contents($folder . "/" . $tmpFilename, $input);
// get MIME type of file
$mime = mime_content_type($folder . "/" . $tmpFilename);
$type = explode("/", $mime);
// set MIME type at file
$filename = $tmpFilename . "." . $type[1];
// rename file including MIME type
rename($folder . "/" . $tmpFilename, $folder . "/" . $filename);
// to echo file 
// header("Content-Type: " . $type); 
// echo file_get_contents($newName);
echo $filename . " created";
?>