Motivation:
According to the MQTT 3.1.1 Protocol Specification: The Server MUST validate that the reserved flag in the CONNECT Control Packet is set to zero and disconnect the Client if it is not zero. (http://docs.oasis-open.org/mqtt/mqtt/v3.1.1/os/mqtt-v3.1.1-os.html#_Toc385349230)
Resolves#4182
Modifications:
Check the CONNECT reserved flag for MQTT 3.1.1. If it's not 0, throw an exception.
Result:
If the CONNECT reserved flag, a decode failure will be emitted.
Motivation:
MQTT 3.1.1 became an OASIS Standard at 13 Nov 2014.
http://docs.oasis-open.org/mqtt/mqtt/v3.1.1/mqtt-v3.1.1.html
MQTT 3.1.1 is a minor update of 3.1. But, previous codec-mqtt supported only MQTT 3.1.
Modifications:
- Add protocol name `MQTT` with previous `MQIsdp` for `CONNECT`’s variable header.
- Update client identifier validation for 3.1 with 3.1.1.
- Add `FAILURE (0x80)` for `SUBACK`’s new error code.
- Add a test for encode/decode `CONNECT` of 3.1.1.
Result:
MqttEncoder/MqttDecoder can encode/decode frames of 3.1 or 3.1.1.
- Use simple string concatenation instead of String.format()
- Rewrite exception messages so that it follows our style
- Merge MqttCommonUtil and MqttValidationUtil into MqttCodecUtil
- Hide MqttCodecUtil from users
- Rename MqttConnectReturnCode.value to byteValue
- Rename MqttMessageFactory.create*() to new*()
- Rename QoS to MqttQoS
- Make MqttSubAckPayload.grantedQoSLevels immutable and add more useful
constructor
MQTT is a open source protocol on top of TCP which is widely used in
mobile communication and also for IoT (Internet of Things) today. This
will add an open source implementation of MQTT so that it becomes easier
for Netty users to implement an MQTT application.
For more information about the MQTT protocol, read this:
http://public.dhe.ibm.com/software/dw/webservices/ws-mqtt/mqtt-v3r1.html
