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MQTT Vehicle Session?

Hi,  I can't seem to figure out how to get the most recent charging session informaiton from MQTT (or RAPI).


I see that the web UI can show the last charge energy and elapsed time, but there doesn't seem to be a standard MQTT for this.


Maybe I can get it through a request/response with RAPI but I can't figure that out either.


Thank you!

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To get the most-recent charging session (since last unplugged) energy use, publish a message to openevse/rapi/in/$GU and it will respond to openevse/rapi/out with something like $OK 40629846 165327^27


The first number is the most recent session energy in watt-seconds and the second number is the total energy in watt-hours (the ^27 is a checksum from what I read in the source code.)


Unfortunately since every RAPI message is published to a generic topic (/rapi/out), it is impossible to know for sure that message is in response to a particular request.  With my current level-of-knowlege, I cannot use the MQTT RAPI reliably.  I wish that the MQTT RAPI API published the responses to something like /rapi/out/$XX instead of just /rapi/out, then it would be trivial to assign responses correctly even in a multithreaded environment.


Fortunately there is the HTTP REST API and that is what I am using with Home Assistant at the moment.


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