Exemple #1
0
    def fill_ranges(self, start, end, length):
        """
        Fill the request ranges.
        """
        if length == 0:
            return

        if self.buf_size:
            # discard bytes
            # so we only yield complete EC segments
            self.discard_bytes = discard_bytes(self.buf_size, start)

        # change headers for efficient recovery
        if 'Range' in self.request_headers:
            try:
                orig_ranges = utils.ranges_from_http_header(
                    self.request_headers['Range'])
                new_ranges = [(start, end)] + orig_ranges[1:]
            except ValueError:
                new_ranges = [(start, end)]
        else:
            new_ranges = [(start, end)]

        self.request_headers['Range'] = utils.http_header_from_ranges(
            new_ranges)
Exemple #2
0
    def recover(self, nb_bytes):
        """
        Recover the request.

        :params nb_bytes: number of bytes already consumed that we need to
                          discard if we perform a recovery from another source.

        :raises ValueError: if range header is not valid
        :raises UnsatisfiableRange
        :raises EmptyByteRange
        """
        if 'Range' in self.request_headers:
            request_range = utils.ranges_from_http_header(
                self.request_headers['Range'])
            start, end = request_range[0]
            if start is None:
                # suffix byte range
                end -= nb_bytes
            else:
                start += nb_bytes
            if end is not None:
                if start == end + 1:
                    # no more bytes to serve in the requested byte range
                    raise exc.EmptyByteRange()
                if start > end:
                    # invalid range
                    raise exc.UnsatisfiableRange()
                if end and start:
                    # full byte range
                    request_range = [(start, end)] + request_range[1:]
                else:
                    # suffix byte range
                    request_range = [(None, end)] + request_range[1:]
            else:
                # prefix byte range
                request_range = [(start, None)] + request_range[1:]

            self.request_headers['Range'] = utils.http_header_from_ranges(
                request_range)
        else:
            # just add an offset to the request
            self.request_headers['Range'] = 'bytes=%d-' % nb_bytes