micropython-thingspeak

Library for sending data to thingspeak.com from IoT devices running MicroPython (such as ESP8266).

Features

• Supports HTTP and HTTPS API (extension is possible)
• Automatically calculates delay required to conform to Free plan
• Allows naming channels (you can use Humidity instead of cryptic field1 required by the API)
• Resolves thingspeak.com IP address only once
• Optionally logs sent values to console

Usage guide

Download the library and put it in the lib folder of your project (see esp8266-deploy-micropython for easy deployments!).

Get ThingSpeak API keys

1. Login on ThingSpeak website
2. Go to Channels/My channels
3. Choose a channel
4. Go to API Keys tab
5. Make note of the Write API Key

Configure channels

API rate limiting is calculated based on number of channels. So it is necessary to specify all your active channels, even if they are not used on current device.

Each channel requires a name (for logging and self-defensive coding), Write API key () and list of field names.

Field names are internally transformed into field1 ... fieldN so they need to be in this order.

from thingspeak import Channel

channel_living_room = "living room"
channel_bedroom = "bedroom"
active_channel = channel_living_room

field_temperature = "Temperature"
field_humidity = "Humidity"

channels = [
    Channel(channel_living_room, '<API KEY>', [field_temperature, field_humidity]),
    Channel(channel_bedroom, '<API KEY>', [field_temperature, field_humidity])
]

Create API instance

By default will library use HTTP protocol and logging is turned off.

from thingspeak import ThingSpeakAPI, ProtoHTTPS

thing_speak = ThingSpeakAPI(channels, protocol_class=ProtoHTTPS, log=True)

Send values

import machine
import time
import dht

dht_sensor = dht.DHT22(machine.Pin(0))

while True:
    try:
        dht_sensor.measure()
    except OSError:
        continue

    thing_speak.send(active_channel, {
        field_temperature: dht_sensor.temperature(),
        field_humidity: dht_sensor.humidity()
    })

    time.sleep(thing_speak.min_delay)

ThingSpeak.send() returns False when sending values fails. This is in most cases due to a wrong API key.

Examples

You can find a working example of sending values from DHT22 on ESP8266 in src/main.py.

Testing

There are unit tests present in the tests directory. Before running them, set API_KEY environment variable to a Write API Key of some testing channel.