labview-open-source/lv-mqtt-control-packets

MQTT Control Packets library

lv-mqtt-control-packets's Issues

Extend acceptable client identifiers to include wider range of characters

Currently, the control packets will accept only lexical classes 3 thru 5, or 0. Consider the possibility to extend to a subset of class 6, which includes common characters such as "hyphen" and "underscore".

Examples of acceptable client identifiers:

• "clientID"
• "clientID5634765328765"

But those are currently rejected, although they are compatible with the server:

• "clientID47_2"
• "client-47"

Recommendation:

• Include a subset of acceptable characters such as _ - % ~ + @

Affected method: MQTT_Control_Packet.lvlib:ControlPacket.lvclass:Encode ClientID.vi

Packet private data should hold all info to allow reconstructing original of invalid packets

Current Packet Private Data does not hold the source bytes in a way that allow recreating the original incoming bytes if we detect an invalid packet format.

Packet should hold an original copy of the input stream instead of only caching the result of the decoding.
Use invalid packet type 00 to output invalid source stream when called.

In a nutshell, this is incorrect when the validation fails.

Support for v3.1 sub protocol (Paho Library)

The Paho library for Websockets uses a subprotocol version for distinction between 3.1 and 5.0 of MQTT.
As such, the CONNECT packet's variable header can have a different protocol name (0x00, 0x06 instead of 0x00-0x04).

Verify requirement change to support subprotocol. MQTT spec mentions that server MAY support subprotocols if desired. To be able to use the Paho WS library for javascript, this would be a nice-to-have in the control packets parsing algorithm.

http://docs.oasis-open.org/mqtt/mqtt/v3.1.1/os/mqtt-v3.1.1-os.html#_Toc398718083

Packet ID should never be 0x0000 when it rolls over

https://docs.oasis-open.org/mqtt/mqtt/v3.1.1/os/mqtt-v3.1.1-os.html#_Toc398718025:~:text=SUBSCRIBE%2C%20UNSUBSCRIBE%2C%20and%20PUBLISH%20(in%20cases%20where%20QoS%20%3E%200)%20Control%20Packets%20MUST%20contain%20a%20non%2Dzero%2016%2Dbit%20Packet%20Identifier%20%5BMQTT%2D2.3.1%2D1%5D

Connect payload does not properly decode the password

The password is encoded with a prepended length.
getConnectPayload.vi should instead remove the prepended length using the Decode text String with UTF flag = false.

Support packet format for MQTT v5.0

https://docs.oasis-open.org/mqtt/mqtt/v5.0/mqtt-v5.0.html

Expose "Has Control Packet" publicly

Needed to resolve this issue on the handling of responses when no packet IDs.
LabVIEW-Open-Source/MQTT-Connection#8