who send mqtt message to topic

[yuexian1234]

i find the cloud app code is just update the device status, and the edge app just subcribe the mqtt topic. i want to know,who send message to mq topic? kubeedge controller or cloudapp self. thanks

[RyanZhaoXB]

hello. the cloud app updates the device status to kube-apiserver and the module of device controller in cloudcore will watch the modification and send it to the edgecore through cloudhub. the module of devicetwin in edgecore will rebuild the message and send it to the mq topic through event bus.

[yuexian1234]

hello. the cloud app updates the device status to kube-apiserver and the module of device controller in cloudcore will watch the modification and send it to the edgecore through cloudhub. the module of devicetwin in edgecore will rebuild the message and send it to the mq topic through event bus.

thanks but how the edgecore known which topic to send?

[RyanZhaoXB]

hello. the cloud app updates the device status to kube-apiserver and the module of device controller in cloudcore will watch the modification and send it to the edgecore through cloudhub. the module of devicetwin in edgecore will rebuild the message and send it to the mq topic through event bus.

thanks but how the edgecore known which topic to send?

we make it in the code of edgecore and mapper. every mapper on this node subscribes these topics to receive the messages and the mapper will check the device id to determine whether the message should be handled by itself.