jquery-file-upload.js

    $('.doc input').fileupload(
    {
        url: WP_Ajax.ajaxurl,
        sequentialUploads: true,
        formData: {action: 'upload_file'},

        add: function (e, data) {
            var uploadErrors = [];

            var acceptFileTypes = /\/(pdf|JPEG|JPG|TIFF|GIF|png|BMP|DOC|DOCX|XLS|XLSX|ODT|ODS)$/i;
            if(data.originalFiles[0]['type'].length && !acceptFileTypes.test(data.originalFiles[0]['type'])) {
                uploadErrors.push('File type not accepted');
            }

            if (data.originalFiles[0]['size'] > 10000000) {
                uploadErrors.push('Filesize too big. Maximum file size should be 10 MB');
            }
            if(uploadErrors.length > 0) {
                swal("", uploadErrors.join("\n"), "error");
            } else {
                data.context = $('<p/>').text('Uploading...').appendTo(document.body);
                data.submit();
            }
        },
        done: function(e, data){
            var html = data.result + '<a class="remove-file"><i class="fa fa-minus-circle"></i></a>';
            $(e.target).closest('.doc').find('.file-name').html(html);
            documentProgress();
        }


    });