上传文件返回的json数据会被提示下载问题解决方案

def jsonp(func):
    """Wraps JSONified output for JSONP requests."""
    @wraps(func)
    def decorated_function(*args, **kwargs):
        callback = request.args.get('callback', False)
        temp_content =  func(*args, **kwargs)
        if isinstance(temp_content, dict):
            temp_content.setdefault('success', True)
            temp_content.setdefault('code', 200)
            try:
                temp_content = json.dumps(temp_content, indent=4)
            except UnicodeDecodeError:
                try:
                  temp_content = ujson.dumps(temp_content)
                except StandardError as e:
                  logger.exception(e)
                  temp_content = json.dumps({'success': False, 'code': 500, 'info': 'INVALID_CONTENT'})
            temp_content = cgi.escape(temp_content)
            if callback:
                # 依据 http://evilcos.me/?p=425，jsonp添加/**/头部会安全一些
                content = '/**/' + str(callback) + '(' + temp_content + ')'
                mimetype = 'application/javascript'
                headers = {'charset':'utf-8'}
                return current_app.response_class(content, mimetype=mimetype,headers=headers)
            else:
                mimetype = 'application/json'
                headers = {'charset':'utf-8'}
                content = temp_content
                return current_app.response_class(content, mimetype=mimetype,headers=headers)
        elif isinstance(temp_content, basestring):
            temp_content = cgi.escape(temp_content)
            return temp_content
        else:
            return temp_content
    return decorated_function
@mod.route('/patch/install.json', methods=['POST'])
@jsonp
def patch_install():
    return {'data': 'data'}

$('#form').ajaxSubmit({
    url      : '/patch/install.json',
    type     : 'post',
    dataType : 'json',
    iframe   : true,
    success: function(res) {
        // code
    }
});

def plain(func):
    """wrap text/html reponse"""
    @wraps(func)
    def _inner(*args, **kwargs):
        resp = func(*args, **kwargs)
        if isinstance(resp, dict):
            resp.setdefault('success', True)
            resp.setdefault('code', 200)
            resp = json.dumps(resp)
            resp = cgi.escape(resp)
            return current_app.response_class(resp, mimetype='text/html', headers={'charset': 'utf-8'})
        elif isinstance(resp, basestring):
            resp = cgi.escape(resp)
            return current_app.response_class(resp, mimetype='text/html', headers={'charset': 'utf-8'})
        else:
            return resp
    return _inner
@mod.route('/patch/install.json', methods=['POST'])
@plain
def patch_install():
    return {'data': 'data'}