HelloZeroNet/ZeroNet · error · Exception

Invalid type: %s

Error message

Invalid type: %s

What it means

Piecefield.frombytes initializes the piecefield from raw bytes. It raises Exception("Invalid type: %s") when s is not bytes or bytearray — e.g. a str arriving from JSON storage or protocol decoding. This keeps the internal invariant that self.data is always a bytes blob.

Source

Thrown at plugins/Bigfile/BigfilePiecefield.py:71

    if len(data) < idx:
        data = data.ljust(idx + 1, b"\x00")
    return data[:idx] + bit + data[idx+ 1:]

class Piecefield(object):
    def tostring(self):
        return "".join(["1" if b else "0" for b in self.tobytes()])


class BigfilePiecefield(Piecefield):
    __slots__ = ["data"]

    def __init__(self):
        self.data = b""

    def frombytes(self, s):
        if not isinstance(s, bytes) and not isinstance(s, bytearray):
            raise Exception("Invalid type: %s" % type(s))
        self.data = s

    def tobytes(self):
        return self.data

    def pack(self):
        return packPiecefield(self.data).tobytes()

    def unpack(self, s):
        self.data = unpackPiecefield(array.array("H", s))

    def __getitem__(self, key):
        try:
            return self.data[key]
        except IndexError:
            return False

    def __setitem__(self, key, value):

View on GitHub (pinned to 454c0b2e7e)

Solutions

1. Convert before calling: s = s.encode("latin1") if isinstance(s, str) else bytes(s).
2. Persist piecefields as base64/bytes-safe format so they load back as bytes.
3. Check for None/missing DB values and use an empty Piecefield instead.
4. Add a loader helper that validates the type before frombytes.

Example fix

// before
piecefield.frombytes(piece_data)  # str from JSON
// after
if isinstance(piece_data, str):
    piece_data = piece_data.encode("latin1")
if piece_data:
    piecefield.frombytes(piece_data)

if not isinstance(s, (bytes, bytearray)):
    s = s.encode("latin1") if isinstance(s, str) else bytes(s or b"")

def is_bytes_like(s):
    return isinstance(s, (bytes, bytearray))

try:
    piecefield.frombytes(s)
except Exception as e:
    if "Invalid type" in str(e):
        piecefield.frombytes(s.encode("latin1") if isinstance(s, str) else b"")
    else:
        raise

When it happens

Trigger: Loading a big file's piecefield from a source that decoded it to str (JSON round-trip, msgpack with text mode), passing memoryview/array('H'), or None when the DB value is missing.

Common situations: Piecefields stored in sites.json as latin1-mangled strings; upgrading ZeroNet where storage format changed; third-party code passing str piecefield read via .encode() elsewhere.

Related errors

• Invalid data type: %s
• Invalid bit: %s
• Style values must be strings
• Style values must be strings
• Unable to download piecemap: %s

AI-assisted analysis of HelloZeroNet/ZeroNet@454c0b2e7e (2026-09-02). Data as JSON: /api/errors/fa4e7a1355e5fe51. Report an issue: GitHub.