# Help with bridging a Python script over to Losant

**URL:** <https://forums.losant.com/t/help-with-bridging-a-python-script-over-to-losant/905>\
**Category:** Help\
**Created:** [May 12, 2018, 4:36pm UTC](https://forums.losant.com/t/help-with-bridging-a-python-script-over-to-losant/905 "2018-05-12T16:36:33Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![Mike\_Chapman](https://avatars.discourse-cdn.com/v4/letter/m/6bbea6/32.png) [@Mike\_Chapman](https://forums.losant.com/u/Mike_Chapman)\
**Post date:** [May 12, 2018, 4:36pm UTC](https://forums.losant.com/t/help-with-bridging-a-python-script-over-to-losant/905/1 "2018-05-12T16:36:33Z")

</div>

Hi,

I have a Python script that I would like to see if someone would be willing to look at and see if they could help me with bridging it over to Losant. I can post it here in the forums if so.

Thanks,

Mike

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<div class="post-metadata">

**Author:** ![Dylan\_Schuster](https://sea1.discourse-cdn.com/flex015/user_avatar/forums.losant.com/dylan_schuster/32/2850_2.png) [@Dylan\_Schuster](https://forums.losant.com/u/Dylan_Schuster)\
**Post date:** [May 12, 2018, 8:53pm UTC](https://forums.losant.com/t/help-with-bridging-a-python-script-over-to-losant/905/2 "2018-05-12T20:53:45Z")

</div>

We have Python clients for connecting to our [MQTT broker](https://github.com/Losant/losant-mqtt-python) and for interacting with our [REST API](https://github.com/Losant/losant-rest-python). If you’re not using those already I would suggest you start there.

If you’re having trouble after that, feel free to post a code sample and let us know the specific issue you’re having and we’ll be happy to take a look.

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<div class="post-metadata">

**Author:** ![Tim\_Hoffman](https://avatars.discourse-cdn.com/v4/letter/t/ebca7d/32.png) [@Tim\_Hoffman](https://forums.losant.com/u/Tim_Hoffman)\
**Post date:** [May 16, 2018, 8:14am UTC](https://forums.losant.com/t/help-with-bridging-a-python-script-over-to-losant/905/3 "2018-05-16T08:14:08Z")

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We use python (for pretty much everything) and don’t use the Losant python library.  
We use the paho mqtt lib and our python agents either talk directly to Losant (TLS) or via a local mosquitto broker.

The only difference is the setup and connection type.

May be you should include a some detail on what you are trying to do.

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<div class="post-metadata">

**Author:** ![Mike\_Chapman](https://avatars.discourse-cdn.com/v4/letter/m/6bbea6/32.png) [@Mike\_Chapman](https://forums.losant.com/u/Mike_Chapman)\
**Post date:** [May 19, 2018, 12:36pm UTC](https://forums.losant.com/t/help-with-bridging-a-python-script-over-to-losant/905/4 "2018-05-19T12:36:12Z")

</div>

Hi Tim,

I will paste the script below. One of the things I am not certain about would be how to bridge this over to Losant.

#!/usr/bin/env python  
“”" \example x4m300\_presence\_simpleoutput.py  
This is an example of how to set up and read presence single messages from the  
X4M300 module with the ModuleConnector python wrapper.  
“”"  
from **future** import print\_function  
import numpy as np  
import time  
from pymoduleconnector import ModuleConnector  
from pymoduleconnector.ids import \*  
from time import sleep  
import paho.mqtt.client as mqtt  
import paho.mqtt.publish as publish  
import json

############### Define MQTT ##################

Broker = “raspberrypi.local”  
pub\_change\_topic = “presence/human/change/livingroom”  
pub\_detail\_topic = “presence/human/detail/livingroom”

def on\_connect(client, userdata, flags, rc):  
print("Connected MQTT with result code " + str(rc))

client = mqtt.Client()  
client.connect(Broker, 1883, 60)  
client.loop\_start()

def publishChange(isPresent):

```
print("publishChange: " + str(isPresent))
client.publish(pub_change_topic, str(isPresent).lower(), 1)

```

#@rate\_limited(5000)  
def publishDetail(isPresent, presenceState, distance, signalQuality):

```
print("publishDetail: " + str(presenceState))
jsonObj = json.dumps({'isPresent': isPresent,
                      'presenceState': presenceState,
                      'distance': distance,
                      'signalQuality': signalQuality})

client.publish(pub_detail_topic, str(jsonObj), 0)

```

############### Define MQTT ##################

def x4m300\_presence\_simpleoutput(device\_name, detection\_zone=(0.5, 9), sensitivity=5, num\_messages=0):

```
# User settings
detzone_start = detection_zone[0]
detzone_end = detection_zone[1]

presence_state_text = []
presence_state_text.append("No presence")
presence_state_text.append("Presence")
presence_state_text.append("Initializing")

mc = ModuleConnector(device_name, log_level=0)
x4m300 = mc.get_x4m300()

sleep(1) # Allow for MC to read waiting messages from module.

try:
    # Make sure no profile is running.
    x4m300.set_sensor_mode(XTID_SM_STOP, 0)
    print("Stopped already running profile.")
except RuntimeError:
    # If not initialized, stop returns error. Still OK, just wanted to make sure the profile was not running.
    pass

# Now flush old messages from module
print("Flushing any old data.")
while x4m300.peek_message_presence_single():
    presence_single = x4m300.read_message_presence_single()

# Read module info
print("FirmwareID:", x4m300.get_system_info(XTID_SSIC_FIRMWAREID))
print("Version:", x4m300.get_system_info(XTID_SSIC_VERSION))
print("Build:", x4m300.get_system_info(XTID_SSIC_BUILD))
print("Serial number:", x4m300.get_system_info(XTID_SSIC_SERIALNUMBER))

print("Loading new profile.")
x4m300.load_profile(XTS_ID_APP_PRESENCE_2)

print("Selecting module output.")

############### Turn LED off ##################
x4m300.set_led_control(0, 0)
############### Turn LED off ##################

x4m300.set_output_control(XTS_ID_PRESENCE_SINGLE, 1) # PresenceSingle
x4m300.set_output_control(
    XTS_ID_PRESENCE_MOVINGLIST, 0) # PresenceMovingList

print("Setting user settings: DetectionZone = " + str(detzone_start) +
      " to " + str(detzone_end) + ", Sensitivity = " + str(sensitivity))
x4m300.set_detection_zone(detzone_start, detzone_end)
x4m300.set_sensitivity(sensitivity)

print("Start profile execution.")
x4m300.set_sensor_mode(XTID_SM_RUN, 0) # Make sure no profile is running.

print("Waiting for data...")

############### Previous State Var ##################
lastPresenceState = ''
lastDistance = 0
lastSignalQuality = 0

presenceState = ''
distance = 0
signalQuality = 0
############### Previous State Var ##################

n = 0
while num_messages == 0 or n < num_messages:
    time.sleep(0.1)

    while x4m300.peek_message_presence_single():
        presence_single = x4m300.read_message_presence_single()

        ############### Call MQTT ##################

        presenceState = presence_state_text[presence_single.presence_state]
        distance = str(round(presence_single.distance, 2))
        signalQuality = str(presence_single.signal_quality)

        isPresent = True if presenceState == 'Presence' else False

        hasPresenceStateChanged = presenceState != lastPresenceState
        if hasPresenceStateChanged:
            publishChange(isPresent)

        if hasPresenceStateChanged or distance != lastDistance or signalQuality != lastSignalQuality:
            publishDetail(isPresent, presenceState,
                          distance, signalQuality)

        lastPresenceState = presenceState
        lastDistance = distance
        lastSignalQuality = signalQuality

        print("Presence ->"
              + " FrameCounter: " + str(presence_single.frame_counter)
              + ", State: " + presenceState
              + ", Distance: " + distance
              + ", SignalQuality: " + signalQuality
              )
        ############### Call MQTT ##################

        n += 1

x4m300.set_sensor_mode(XTID_SM_STOP, 0)

```

def main():  
import sys  
from optparse import OptionParser  
parser = OptionParser()  
parser.add\_option(  
“-d”,  
“–device”,  
dest=“device\_name”,  
help=“device file to use, example: python %s -d COM4” % sys.argv[0],  
metavar=“FILE”)

```
parser.add_option(
    "-n",
    "--num-messages",
    dest="num_messages",
    type=int,
    default=0,
    help="how many messages to read (0 = infinite)",
    metavar="INT")

parser.add_option('-z', '--detection_zone', nargs=2, type='float',
                  help='Start and stop of detection zone.', metavar='START STOP',
                  default=(0.5, 9))

parser.add_option('-s', '--sensitivity', nargs=1, type='int',
                  help='Sensor Sensitivity.', metavar='SENSITIVITY',
                  default=5)

(options, args) = parser.parse_args()

if not options.device_name:
    print("Please specify a device name, example: python %s -d COM4" %
          sys.argv[0])
    sys.exit(1)
x4m300_presence_simpleoutput(**vars(options))

```

if **name** == “ **main** ”:  
main()

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<div class="post-metadata">

**Author:** ![Tim\_Hoffman](https://avatars.discourse-cdn.com/v4/letter/t/ebca7d/32.png) [@Tim\_Hoffman](https://forums.losant.com/u/Tim_Hoffman)\
**Post date:** [May 20, 2018, 10:02am UTC](https://forums.losant.com/t/help-with-bridging-a-python-script-over-to-losant/905/5 "2018-05-20T10:02:30Z")

</div>

Hi Mike

The first thing to consider is the mismatch between your topics for presence and how Losant works.

You should start by having a read up Losant’s topic structure.

its `losant/<deviceid>/state` to report the state of a device. The payload is a json formated set of key value pairs. Which is quite different to the structure of the topics in your sample code.

Think about what and why you want to report data to Losant and look at what you trying to achieve. Some of the implied state based on your topics would then translate into a name/value pair that is part of the payload.