View source for MISC-TN-026: Automated test equipment (ATE) monitoring with SBCSPG gateway, ThingsBoard IoT, and Fledge

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[[Category:MISC-AN-TN]]
[[Category:MISC-TN]]

__FORCETOC__
== History ==
{| class="wikitable" border="1"
!Version
!Date
!Notes
|-
|1.0.0
|February 2023
|First public release
|-
|}

==Introduction==
In essence, this Technical Note (TN) is very similar to [[MISC-TN-024: Automated test equipment (ATE) monitoring with SBCSPG gateway and ThingsBoard IoT platform|''MISC-TN-024: Automated test equipment (ATE) monitoring with SBCSPG gateway and ThingsBoard IoT platform'']]. There is a noticeable difference, however, as a different software stack was used on the edge device. In this case, [https://www.lfedge.org/projects/fledge/ Fledge] was utilized.

==Testbed==
The edge device is the [[MISC-TN-004:_Running_Debian_(armbian)_on_SBCSPG#The_hardware_platform|SBCSPG gateway]] running Debian Bullseye. To deploy this distribution onto the target, the same approach described [[ORCA-TN-001_—_Running_Armbian_Bullseye_(Debian_11)|here]] was used. Unlike Orca SBC, SBCSPG is based on a 32-bit ARM Cortex-A7 processor, though. As such, a [https://mirrors.dotsrc.org/armbian-dl/tritium-h3/archive/Armbian_22.11.1_Tritium-h3_bullseye_current_5.15.80_minimal.img.xz different image] was used.

To install Fledge, the <code>apt</code>-based approach described [https://fledge-iot.readthedocs.io/en/latest/quick_start/installing.html here] was followed. It is worth to remember that some dependencies were handled manually. For instance, <code>autoconf</code> and <code>libtool</code> packages were installed manually.

===Enabling the connection to the PLC===
As described in [[MISC-TN-024: Automated test equipment (ATE) monitoring with SBCSPG gateway and ThingsBoard IoT platform|''MISC-TN-024'']], the PLC we want to talk to is connected to a different subnet, namely 192.168.30.0/24. For testing the connection to the PLC, after adding the required subnet configuration, the <code>modbus</code> command line tool was used, which is provided by the <code>modbus_cli</code> package. In the following example, the register mapped ad the address 300 is read.

<pre class="board-terminal">
root@sbcspg:/usr/local/fledge/python/fledge/plugins/north# ip addr add 192.168.30.253/24 dev eth0 label eth0:1

armbian@sbcspg:~/devel/fledge$ pip install modbus_cli
Defaulting to user installation because normal site-packages is not writeable
Requirement already satisfied: modbus_cli in /home/armbian/.local/lib/python3.9/site-packages (0.1.8)
Requirement already satisfied: colorama in /home/armbian/.local/lib/python3.9/site-packages (from modbus_cli) (0.4.6)
Requirement already satisfied: umodbus in /home/armbian/.local/lib/python3.9/site-packages (from modbus_cli) (1.0.4)
Requirement already satisfied: pyserial~=3.4 in /usr/local/lib/python3.9/dist-packages (from umodbus->modbus_cli) (3.5)

[notice] A new release of pip is available: 23.0 -> 23.0.1
[notice] To update, run: python3 -m pip install --upgrade pip
...
armbian@sbcspg:~$ ./.local/bin/modbus 192.168.30.42:502 300
Parsed 0 registers definitions from 1 files
300: 32 0x20
</pre>

We then configured Fledge in order to read periodically a couple of PLC's registers. Please note that this is a no-code operation as it is carried out with the help of the native web-based Fledge UI. To access PLC exposed data, the Fledge's <code>modbustcp</code> South plugin was used. Please note that also we had to patch it manually to solve a bug that prevented it from working properly. The patch is detailed [https://github.com/fledge-iot/fledge-south-modbustcp/pull/26/files here]. To make the change effective, we disabled and re-enabled the plugin via the web interface. 

[[File:SBCSPG-Fledge-2.png|center|thumb|600x600px|Installing the <code>modbustcp</code> South plugin.]]
[[File:SBCSPG-Fledge-3.png|center|thumb|600x600px|Configuring the plugin]]
[[File:SBCSPG-Fledge-4.png|center|thumb|600x600px|Configuring the plugin.]]
[[File:SBCSPG-Fledge-5.png|center|thumb|600x600px|The plugin is enabled.]]
[[File:SBCSPG-Fledge-6.png|center|thumb|600x600px|Fledge provides a native web interface to visualize collected data. ]]


=== Enabling the connection to ThingsBoard IoT platform ===
In order to upload collected data to ThingsBoard platform, a simple North plugin was developed. To this end, the Microsoft Azure plugin was used as reference. The ThingsBoard North plugin is minimalist and '''unfit for a real-world production environment'''. Nevertheless, it was enough to perform the basic tests described in this document. Before testing this new plugin, the <code>mosquitto-clients</code> package was installed as the plugin invokes the <code>mosquitto_pub</code> command line tool.

<pre class="board-terminal">
root@sbcspg:/usr/local/fledge/python/fledge/plugins/north# apt install mosquitto mosquitto-clients
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
The following additional packages will be installed:
  libcjson1 libdlt2 libev4 libmosquitto1 libwebsockets16
Suggested packages:
  apparmor
The following NEW packages will be installed:
  libcjson1 libdlt2 libev4 libmosquitto1 libwebsockets16 mosquitto mosquitto-clients
0 upgraded, 7 newly installed, 0 to remove and 8 not upgraded.
Need to get 715 kB of archives.
After this operation, 1,492 kB of additional disk space will be used.
Do you want to continue? [Y/n] 
Get:1 http://deb.debian.org/debian bullseye/main armhf libcjson1 armhf 1.7.14-1 [20.5 kB]
Get:2 http://deb.debian.org/debian bullseye/main armhf libdlt2 armhf 2.18.6-1+deb11u1 [46.1 kB]
Get:3 http://deb.debian.org/debian bullseye/main armhf libev4 armhf 1:4.33-1 [38.6 kB]
Get:4 http://deb.debian.org/debian bullseye/main armhf libmosquitto1 armhf 2.0.11-1 [83.5 kB]
Get:5 http://deb.debian.org/debian bullseye/main armhf libwebsockets16 armhf 4.0.20-2 [163 kB]
Get:6 http://deb.debian.org/debian bullseye/main armhf mosquitto armhf 2.0.11-1 [253 kB]
Get:7 http://deb.debian.org/debian bullseye/main armhf mosquitto-clients armhf 2.0.11-1 [110 kB]
Fetched 715 kB in 0s (1,817 kB/s)      
Selecting previously unselected package libcjson1:armhf.
(Reading database ... 72206 files and directories currently installed.)
Preparing to unpack .../0-libcjson1_1.7.14-1_armhf.deb ...
Unpacking libcjson1:armhf (1.7.14-1) ...
Selecting previously unselected package libdlt2:armhf.
Preparing to unpack .../1-libdlt2_2.18.6-1+deb11u1_armhf.deb ...
Unpacking libdlt2:armhf (2.18.6-1+deb11u1) ...
Selecting previously unselected package libev4:armhf.
Preparing to unpack .../2-libev4_1%3a4.33-1_armhf.deb ...
Unpacking libev4:armhf (1:4.33-1) ...
Selecting previously unselected package libmosquitto1:armhf.
Preparing to unpack .../3-libmosquitto1_2.0.11-1_armhf.deb ...
Unpacking libmosquitto1:armhf (2.0.11-1) ...
Selecting previously unselected package libwebsockets16:armhf.
Preparing to unpack .../4-libwebsockets16_4.0.20-2_armhf.deb ...
Unpacking libwebsockets16:armhf (4.0.20-2) ...
Selecting previously unselected package mosquitto.
Preparing to unpack .../5-mosquitto_2.0.11-1_armhf.deb ...
Unpacking mosquitto (2.0.11-1) ...
Selecting previously unselected package mosquitto-clients.
Preparing to unpack .../6-mosquitto-clients_2.0.11-1_armhf.deb ...
Unpacking mosquitto-clients (2.0.11-1) ...
Setting up libmosquitto1:armhf (2.0.11-1) ...
Setting up libev4:armhf (1:4.33-1) ...
Setting up libcjson1:armhf (1.7.14-1) ...
Setting up mosquitto-clients (2.0.11-1) ...
Setting up libdlt2:armhf (2.18.6-1+deb11u1) ...
Setting up libwebsockets16:armhf (4.0.20-2) ...
Setting up mosquitto (2.0.11-1) ...
Created symlink /etc/systemd/system/multi-user.target.wants/mosquitto.service → /lib/systemd/system/mosquitto.service.
Processing triggers for libc-bin (2.31-13+deb11u5) ...
</pre>

The following box shows the code of the ThingsBoard plugin.

<syntaxhighlight lang="python" class"mw-collapsible="" mw-collapsed"="">
# -*- coding: utf-8 -*-

""" ThingsBoard North plugin"""
import asyncio
import time
import json
import sys
import os



from fledge.common import logger
from fledge.plugins.north.common.common import *

__author__ = "Andrea Marson"
__copyright__ = "Copyright (c) 2023 DAVE Srl"
__license__ = "Apache 2.0"
__version__ = "${VERSION}"

_LOGGER = logger.setup(__name__)

_CONFIG_CATEGORY_NAME = "THINGSBOARD"
_CONFIG_CATEGORY_DESCRIPTION = "ThingsBoard Python North Plugin"

_DEFAULT_CONFIG = {
    'plugin': {
         'description': 'ThingsBoard North Plugin',
         'type': 'string',
         'default': 'thingsboard',
         'readonly': 'true'
    },
    "tb_iot_platform_host": {
            "description": "ThingsBoard IoT platform host.",
            "type": "string",
            "default": "put the public name of your host here",
            "order": "2",
            "displayName": "ThingsBoard IoT platform host"
    },
    "tb_mqtt_topic": {
            "description": "MQTT topic",
            "type": "string",
            "default": "v1/devices/me/telemetry",
            "order": "3",
            "displayName": "MQTT topic",
            'readonly': 'true'
    },
    "tb_device_access_token": {
            "description": "Device's access token.",
            "type": "string",
            "default": "put your device's token here",
            "order": "4",
            "displayName": "Device's access token"
    },
    "source": {
            "description": "Source of data to be sent on the stream.",
            "type": "enumeration",
            "default": "readings",
            "options": ["readings"],
            "order": "5",
            "displayName": "Source",
            'readonly': 'true'
    }
}

def plugin_info():
    return {
        'name': 'thingsboard',
        'version': '2.1.0',
        'type': 'north',
        'interface': '1.0',
        'config': _DEFAULT_CONFIG
    }

def plugin_init(data):
    _LOGGER.info('Initializing ThingsBoard North Python Plugin')
    global thingsboard_north, config
    thingsboard_north = ThingsBoardNorthPlugin()
    config = data
    _LOGGER.info(f'config = {config}')
    return config

"""
Example of payload

[{'reading': {'base_joint_temperature_deg_C': 34, 'base_joint_current_mA': 2042}, 'asset_code': 'Modbus TCP', 'id': 35613, 'ts': '2023-02-22 16:33:49.961000+00:00', 'user_ts': '2023-02-22 16:33:47.126849+00:00'}, {'reading': {'base_joint_temperature_deg_C': 34, 'base_joint_current_mA': 2045}, 'asset_code': 'Modbus TCP', 'id': 35614, 'ts': '2023-02-22 16:33:49.961000+00:00', 'user_ts': '2023-02-22 16:33:48.126817+00:00'}, {'reading': {'base_joint_temperature_deg_C': 34, 'base_joint_current_mA': 2060}, 'asset_code': 'Modbus TCP', 'id': 35615, 'ts': '2023-02-22 16:33:49.961000+00:00', 'user_ts': '2023-02-22 16:33:49.126827+00:00'}]

Example of upload

mosquitto_pub -d -q 1 -h "$THINGSBOARD_HOST_NAME" -t "v1/devices/me/telemetry" -u "$ACCESS_TOKEN" -m '{"base_joint_temperature_deg_C":33}'
"""
async def plugin_send(data, payload, stream_id):
    try:
        _LOGGER.info(f'ThingsBoard North Python - plugin_send: {stream_id}')
        _LOGGER.info(f'data = {data}')
        _LOGGER.info(f'payload = {payload}')
        _LOGGER.info(f'host = {data["tb_iot_platform_host"]["value"]}')
        for reading in payload:
            _LOGGER.info(f'reading = {reading}')
            _LOGGER.info(f'reading[reading] = {reading["reading"]}')
            s = 'mosquitto_pub -d -q 1 -h "' + data["tb_iot_platform_host"]["value"] + '" -t "' + data["tb_mqtt_topic"]["value"] + '" -u "' + data["tb_device_access_token"]["value"] + '" -m \'' + str(reading["reading"]) + "\'"
            _LOGGER.info(f's = {s}')
            os.system(s)
    except asyncio.CancelledError as ex:
        _LOGGER.exception(f'Exception occurred in plugin_send: {ex}')
    else:
        _LOGGER.info('payload sent successfully')
        return True, payload[len(payload-1)]["id"], len(payload)

def plugin_shutdown(data):
    pass

# TODO: North plugin can not be reconfigured? (per callback mechanism)
def plugin_reconfigure():
    pass

class ThingsBoardNorthPlugin(object):
    """ North ThingsBoard Plugin """


</syntaxhighlight>
== Visualization of uploaded data ==
Similarly to what we did in [[MISC-TN-024: Automated test equipment (ATE) monitoring with SBCSPG gateway and ThingsBoard IoT platform|''MISC-TN-024'']], we created a simple dashboard to visualize in real-time on cloud side collected data as shown in the following example.
[[File:SBCSPG-Fledge-8.png|center|thumb|600x600px|Visualization of uploaded data.]]