Many people believe that using a QOS of 1 or2 will guarantee message delivery but it is not actually the case with node-red, python and probably all MQTT clients. MQTT clients will buffer messages if the connection is lost and the messages are still waiting to be sent. However they will also discard new messages. These messages will need to be buffered and sent when the connection is restored. There are nodes that will do this like q-gate and also nodes that buffer in a sqlite database. In this video we will use a function node to do the buffering. The function nodes will only work with character data and not binary data as they were originally written to buffer file data. Buy me a Coffee -https://www.buymeacoffee.com/steveH5u Flow used in video https://stevesnoderedguide.com/download/node-red-mqtt-message-buffer Tutorial on site http://www.steves-internet-guide.com/mqtt-client-message-queue-delivery/
Many people believe that using a QOS of 1 or2 will guarantee message delivery but it is not actually the case with node-red, python and probably all MQTT clients. MQTT clients will buffer messages if the connection is lost and the messages are still waiting to be sent. However they will also discard new messages. These messages will need to be buffered and sent when the connection is restored. There are nodes that will do this like q-gate and also nodes that buffer in a sqlite database. In this video we will use a function node to do the buffering. The function nodes will only work with character data and not binary data as they were originally written to buffer file data. Buy me a Coffee -https://www.buymeacoffee.com/steveH5u Flow used in video https://stevesnoderedguide.com/download/node-red-mqtt-message-buffer Tutorial on site http://www.steves-internet-guide.com/mqtt-client-message-queue-delivery/