Callback for .execute_command() for DELETE/GET/HEAD requests

def data_from_query(self, cmd):
        """
        Callback for .execute_command() for DELETE/GET/HEAD requests
        """
        res  = None
        ckey = "%s /%s" % (self.command, cmd)

        if not isinstance(self._query_params, dict):
            self._query_params = {}

        if ckey in _NCMD:
            self._cmd = _NCMD[ckey]
        else:
            for key in sorted(_RCMD, key=len, reverse=True):
                if not key.startswith("%s " % self.command):
                    continue

                m = _RCMD[key].name.match(cmd)
                if m:
                    self._cmd = _RCMD[key]
                    self._query_params.update(m.groupdict())
                    break

        try:
            if not self._cmd:
                raise self.req_error(404)

            if not self._cmd.to_log:
                self._to_log = False

            if self._cmd.to_auth:
                self.authenticate(self._cmd.auth_users)

            if self._cmd.static:
                if self._cmd.handler:
                    res = self._cmd.handler(self)

                return self.static_file(cmd, res)

            res = self._cmd.handler(self)

            if not isinstance(res, HttpResponse):
                return self.response_dumps(res)

            return res
        finally:
            self._query_params = {}