snippit of imageit.js

function uploadFile(file) {
    var xhr = new XMLHttpRequest();

    xhr.upload.onprogress = function(e) {
        $( ".progress" ).show();
        var percentComplete = Math.ceil((e.loaded / e.total) * 100);
        $("#info_text").text("Uploaded: " + percentComplete + "%");
        $('.bar').width(percentComplete + "%");
        console.log("Uploaded: " + percentComplete + "%");
    };

    xhr.onload = function() {
        if (xhr.status == 200) {
            console.log(xhr.response);
            hostAddress = top.location.host.toString();      
            url = "http://" + hostAddress + xhr.response;
            window.location = url;
        } else if (xhr.status == 413) {
            alert("The image is too large! It must be 25MB or less.");
        } else {
            alert("Something went wrong whilst uploading. This is probably a bug, so it'll be fixed soon!");
        }
    };

    xhr.onerror = function() {
        alert("Error! Upload failed. Can not connect to server.");
    };

    xhr.open("POST", "/upload", true);
    xhr.setRequestHeader("Content-Type", file.type);
    xhr.send(file);
}

snippit of imageit.py

@app.route('/upload', methods=['POST']) 
def upload():
    if request.method == 'POST':
        file = request.data
        image_type = imghdr.what(file)
        print "test"
        if file:
            file_id = id_generator()
            file_ext = "png"
            print "test"
            filename = file_id + "." + file_ext
            db = get_db()
            print "test"
            db.execute('insert into entries (file_name, title, file_ext) values (?, ?, ?)',
                 [file_id, "", file_ext])
            print "test"
            db.commit()
            image = open(os.path.join(app.config['UPLOAD_FOLDER'], filename), 'w+')
            image.write(request.data)
            image.close()
            print "Uploaded as " + os.path.join(app.config['UPLOAD_FOLDER'], filename)
            return "/view/" + file_id
        else:
            return "NO FILE"