Function DecodePaginationKey

util/query/pagination.go:16–85

DecodePaginationKey parses the pagination key and returns the states, prefix and key to be used by the FilteredPaginate

(key []byte)

// DecodePaginationKey parses the pagination key and returns the states, prefix and key to be used by the FilteredPaginate
func DecodePaginationKey(key []byte) ([]byte, []byte, []byte, []byte, error) {
	if len(key) < 5 {
		return nil, nil, nil, nil, fmt.Errorf("%w: invalid key length", ErrInvalidPaginationKey)
	}

	expectedChecksum := binary.BigEndian.Uint32(key)

	key = key[4:]

	checksum := crc32.ChecksumIEEE(key)

	if expectedChecksum != checksum {
		return nil, nil, nil, nil, fmt.Errorf("%w: invalid checksum, 0x%08x != 0x%08x", ErrInvalidPaginationKey, expectedChecksum, checksum)
	}

	statesC := int(key[0])
	key = key[1:]

	if len(key) < statesC {
		return nil, nil, nil, nil, fmt.Errorf("%w: invalid state length", ErrInvalidPaginationKey)
	}

	states := make([]byte, 0, statesC)
	states = append(states, key[:statesC]...)

	key = key[len(states):]

	if len(key) < 1 {
		return nil, nil, nil, nil, fmt.Errorf("%w: invalid state length", ErrInvalidPaginationKey)
	}

	prefixLength := int(key[0])
	key = key[1:]
	if len(key) < prefixLength {
		return nil, nil, nil, nil, fmt.Errorf("%w: invalid state length", ErrInvalidPaginationKey)
	}

	prefix := key[:prefixLength]

	key = key[prefixLength:]

	if len(key) == 0 {
		return nil, nil, nil, nil, fmt.Errorf("%w: invalid state length", ErrInvalidPaginationKey)
	}

	keyLength := int(key[0])
	key = key[1:]

	if len(key) < keyLength {
		return nil, nil, nil, nil, fmt.Errorf("%w: invalid state length", ErrInvalidPaginationKey)
	}

	pkey := key[:keyLength]

	key = key[keyLength:]
	var unsolicited []byte

	if len(key) > 0 {