Control de retransmisión de JSON WebAPI

Información

La documentación de WebAPI se encuentra en https://webapi.egauge.net . El punto final /ctrl se utiliza para controlar el PRM3.
La biblioteca de Python de eGauge contiene funciones auxiliares para la autenticación y las solicitudes, y está disponible a través de Bitbucket y PyPi . El código de demostración proporcionado por eGauge Systems suele requerir esta biblioteca.
Para interactuar con el servicio de control WebAPI, el usuario autenticado debe tener permiso "Permitido ver todos los datos, cambiar configuraciones y controlar dispositivos desde cualquier lugar".

A partir del firmware v4.4 , el PRM3 puede controlarse con medidores de la serie EG4xxx mediante el punto final /ctrl de la WebAPI eGauge basada en JSON. El siguiente script de Python muestra algunas posibles interacciones con un eGauge PRM3.

#!/usr/bin/env python3

# Example script interacting with an eGauge PRM3 power relay module through a
# meter's WebAPI. The PRM3 must be connected to the eGauge via USB.
# 
# This script uses the eGauge Python library, available from bitbucket or pip:
# https://bitbucket.org/egauge/python/src/master/egauge/
# https://pypi.org/project/egauge-python/
# WebAPI documentation: https://egauge.net/support/webapi

# Requires firmware version 4.4 or greater

from egauge import webapi

URI = "https://device-url"
USR = "my_meter_username"
PWD = "my_meter_password"

dev = webapi.device.Device(URI, webapi.JWTAuth(USR, PWD))

USB_PORT = "USB1" # what USB port the relay is connected to


# get the connected relay(s) information
relays = dev.get("/ctrl/device")
"""eg,
{
    'result':
    [
        {
            'path': ['net.egauge.slowd', 'USB1'],
            'mfg': 'eGauge',
            'model': 'PRM3',
            'sn': '00000004',
            'prot': 'SCPI',
            'link': 'serial',
            'quality': '1',
            'interface': ['relay', 'scpi']
        }
    ]
}
"""

# get the serial number of the PRM3 connected to port USB_PORT
# we use the SN to identify which relay to send commands to
for relay in relays["result"]:
    if USB_PORT in relay["path"]:
        relay_sn = relay["sn"]


# get the control interfaces and available methods for the PRM3 relay
# eg, open_mask, set_mask, get_mask
methods = dev.get("/ctrl/interface")["result"]


# get the relay mask
# https://egauge.net/support/m/prm3/mask
payload = {
    "attrs": {"sn": relay_sn},
    "method": "relay.get_mask",
    "args": []
}

# store the transaction ID of the request
# eg, {'result': {'tid': 897412938}}
tid = dev.post("/ctrl/call", payload)["result"]["tid"]

# get the response. eg, {'result': 3} means relays 0 and 1 are closed, and
# 2 is open https://egauge.net/support/m/prm3/mask
print(dev.get(f"/ctrl/call/{tid}")["result"])


# set the mask to 5 (close relay 0 and 2, open relay 1).
# Use relay.open_mask and relay.close_mask to only open OR close relays
payload = {
    "attrs": {"sn": relay_sn},
    "method": "relay.set_mask",
    "args": [5]
}

# make the request, store the transaction ID
tid = dev.post("/ctrl/call", payload)["result"]["tid"]

# check the transaction response. This should generally be {'result': False}
print(dev.get(f"/ctrl/call/{tid}")["result"])


# we can also send arbitrary SCPI commands, such as configurations.
# here we set the Modbus baud rate to 9600:
payload = {
    "attrs": {"sn": relay_sn},
    "method": "scpi.exec",
    "args": ["MODBus:BAUD 9600"]
}

tid = dev.post("/ctrl/call", payload)["result"]["tid"]

# should be "OK"
print(dev.get(f"/ctrl/call/{tid}")["result"])


# verify the baud
payload = {
    "attrs": {"sn": relay_sn},
    "method": "scpi.exec",
    "args": ["MODBus:BAUD?"]
}

tid = dev.post("/ctrl/call", payload)["result"]["tid"]

# {'result': '9600\r\n'}
print(dev.get(f"/ctrl/call/{tid}")["result"])

Información

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