python - Mqtt : Publish the last line from a file that is periodically updated -


i have arduino board sends periodically temperature txt file. file updating every minute(the new data overwritten not appended).

i want make mqtt client reads file periodically , publishes last received data. client publishes no text.

is there way can ?

here have until now:

import mosquitto import time client=mosquitto.mosquitto("read-file") client.connect("broker.mqttdashboard.com", 1883)  f=open("/home/ioana/date_sensor","rb")  while client.loop()==0:     file=f.read()     client.publish("ioana/test",file) time.sleep(60)

i have little idea of mqtt needs, think should put code

f=open("/home/ioana/date_sensor","rb")

and 

time.sleep(60)

inside while loop, , add file close (near end of while loop)...

import mosquitto import time  client=mosquitto.mosquitto("read-file") client.connect("broker.mqttdashboard.com", 1883)  while client.loop() == 0:     f = open("/home/ioana/date_sensor", "rb")     data = f.read()     client.publish("ioana/test", data)     f.close()     time.sleep(60)

i assuming in while loop time, publishes new temperature values every minute or so.


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