Initial prometheus-yoctotemp-exporter implementation

prometheus-yoctotemp-exporter

@@ -0,0 +1,45 @@
+#!/usr/bin/env python
+
+from prometheus_client import start_http_server, Gauge
+from yoctopuce.yocto_api import YAPI, YRefParam
+from yoctopuce.yocto_temperature import YTemperature
+import sys
+
+HTTP_PORT = 9400
+INTERVAL = 5000
+YOCTO_SENSOR_TEMPERATURE = Gauge(
+        'yocto_sensor_temperature',
+        'Yocto-Temperature sensor temperature value in Celcius'
+        )
+
+if __name__ == '__main__':
+    # Setup the API to use local USB devices
+    errmsg = YRefParam()
+    if YAPI.RegisterHub("usb", errmsg) != YAPI.SUCCESS:
+        sys.exit("Could not initialize USB: " + errmsg.value)
+
+    # Use first YoctoTemerature sensor found.
+    sensor = YTemperature.FirstTemperature()
+    if sensor is None:
+        sys.exit('Did not find any YoctoTemerature sensor.')
+    elif sensor.isOnline():
+        print("YoctoTemerature sensor is ONLINE.")
+    else:
+        sys.exit("I found a sensor but it seems unavailable for some reason. Exiting.")
+
+    # Serve metrics over HTTP.
+    print("Starting prometheus-yoctotemp-exporter on port",
+            "{}...".format(HTTP_PORT), end='')
+    start_http_server(HTTP_PORT)
+    print(" OK.")
+
+    while sensor.isOnline():
+        YOCTO_SENSOR_TEMPERATURE.set(sensor.get_currentValue())
+        YAPI.Sleep(INTERVAL)
+
+    sys.stderr.write("YoctoTemperature sensor disappeared for some reason.")
+
+    # Cleanup.
+    YAPI.FreeAPI()
+    sys.exit("Cleaned up - Now exiting.")
+