v0.47.3

[mqtt5 0.47.3] - 2026-10-09

Fixed

• The QUIC broker decodes MQTT v3.1.1 packets on data streams and in datagrams (#193). Only the control stream knew the protocol version the client connected with. A v3.1.1 SUBSCRIBE or PUBLISH on a client data stream, or a v3.1.1 PUBLISH in a datagram, was decoded as v5 and rejected, and since 0.47.2 the connection was closed with ERROR_PROTOCOL_L0. These readers now wait for CONNECT and decode with the negotiated version.
• A QUIC client reads short messages on broker-opened streams at once (#195). The client kept reading a broker-opened stream until it had 32 bytes before parsing the flow header. A flow header and a PUBLISH with no properties can be shorter than that, which is the usual case for a v3.1.1 subscriber, so the message waited until more data arrived on that stream or the connection closed. The client now parses the header as soon as it is complete.
• A v3.1.1 client can unsubscribe (#194). It could not decode the broker's UNSUBACK, which in v3.1.1 has no properties or reason codes, so unsubscribe() failed with UNSUBACK channel closed and the connection dropped. Fixed in mqtt5-protocol 0.16.1.

[mqtt5-wasm 2.1.6] - 2026-10-09

Fixed

• The wasm broker serves MQTT v3.1.1 clients (#193). It decoded every client packet as v5, so a v3.1.1 client's first SUBSCRIBE, UNSUBSCRIBE or QoS 1 PUBLISH was rejected and its connection dropped. A PUBLISH whose payload started with 0x00 lost that byte. Packets are now decoded with the version the client connected with.
• The wasm client can unsubscribe over v3.1.1 (#194), through mqtt5-protocol 0.16.1.

[mqtt5-protocol 0.16.1] - 2026-10-09

Fixed

• Packet::decode_from_body_with_version decodes a v3.1.1 UNSUBACK (#194). UNSUBACK was decoded as v5 for every version and a v3.1.1 UNSUBACK, which is only a packet identifier, was rejected as malformed. A v3.1.1 UNSUBACK with any payload is still malformed.

Added

• UnsubAckPacket::decode_body_with_version.