STM32: possible problem with strings and adafruit_minimqtt library (AdafruitIO) #2433
Description
I have the Feather STM32F405 Express board. I built firmware for it on Christmas. I have an LPS3x bord connected via QT. If I just print data, everything is fine. If I try to push the data to AdafruitIO, though, I get an error "AttributeError: 'str' object has no attribute 'encode'. When I run
adafruit/Adafruit_CircuitPython_AdafruitIO/examples/mqtt/adafruit_io_simpletest.py it throws the same error and backtrace. Here's the backtrace, code to follow down below.
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code.py output:
Traceback (most recent call last):
File "code.py", line 93, in <module>
File "adafruit_minimqtt.py", line 121, in __init__
AttributeError: 'str' object has no attribute 'encode'
Then I thought maybe something had changed, so I went back to the Adafruit IO guides and could not find resolution.
Then I went to the library bundle 5.x source as of 20191223 and looked at line 121 in adafruit_minimqtt.py. (If you need me to include a snippet here, I will.) There didn't seem t be anything unusual, but I did see the .encode() method that was causing the problem.
Then I just connected to the REPL, created a string and called the same encode method:
Adafruit CircuitPython 5.0.0-beta.2-13-g7387f6092 on 2019-12-27; Feather STM32F405 Express with STM32F405RG
>>> foo = "heresastringtotestwith"
>>> foo.encode('utf-u')
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
AttributeError: 'str' object has no attribute 'encode'
>>>
The last couple of issues I raised LadyAda had to exercise extreme patience with my bumbling, so I hope this is more cohesive and helpful. I still assume I'm just doing something stupid, but people on Discord don't seem to think so.
Here is the code that generated the original backtrace:
# Example of using the Adafruit IO CircuitPython MQTT client
# to subscribe to an Adafruit IO feed and publish random data
# to be received by the feed.
#
# Example by Tony DiCola for Adafruit Industries
# Modified by Brent Rubell for Adafruit Industries, 2019
import time
from random import randint
import board
import busio
from adafruit_esp32spi import adafruit_esp32spi
from adafruit_esp32spi import adafruit_esp32spi_wifimanager
import adafruit_esp32spi.adafruit_esp32spi_socket as socket
from digitalio import DigitalInOut
import neopixel
from adafruit_io.adafruit_io import IO_MQTT
from adafruit_minimqtt import MQTT
### WiFi ###
# Get wifi details and more from a secrets.py file
try:
from secrets import secrets
except ImportError:
print("WiFi secrets are kept in secrets.py, please add them there!")
raise
# If you have an externally connected ESP32:
esp32_cs = DigitalInOut(board.D13)
esp32_ready = DigitalInOut(board.D11)
esp32_reset = DigitalInOut(board.D12)
spi = busio.SPI(board.SCK, board.MOSI, board.MISO)
esp = adafruit_esp32spi.ESP_SPIcontrol(spi, esp32_cs, esp32_ready, esp32_reset)
"""Use below for Most Boards"""
status_light = neopixel.NeoPixel(
board.NEOPIXEL, 1, brightness=0.2
) # Uncomment for Most Boards
"""Uncomment below for ItsyBitsy M4"""
# status_light = dotstar.DotStar(board.APA102_SCK, board.APA102_MOSI, 1, brightness=0.2)
# Uncomment below for an externally defined RGB LED
# import adafruit_rgbled
# from adafruit_esp32spi import PWMOut
# RED_LED = PWMOut.PWMOut(esp, 26)
# GREEN_LED = PWMOut.PWMOut(esp, 27)
# BLUE_LED = PWMOut.PWMOut(esp, 25)
# status_light = adafruit_rgbled.RGBLED(RED_LED, BLUE_LED, GREEN_LED)
wifi = adafruit_esp32spi_wifimanager.ESPSPI_WiFiManager(esp, secrets, status_light)
# Define callback functions which will be called when certain events happen.
# pylint: disable=unused-argument
def connected(client):
# Connected function will be called when the client is connected to Adafruit IO.
# This is a good place to subscribe to feed changes. The client parameter
# passed to this function is the Adafruit IO MQTT client so you can make
# calls against it easily.
print("Connected to Adafruit IO! Listening for DemoFeed changes...")
# Subscribe to changes on a feed named DemoFeed.
client.subscribe("DemoFeed")
def subscribe(client, userdata, topic, granted_qos):
# This method is called when the client subscribes to a new feed.
print('Subscribed to {0} with QOS level {1}'.format(topic, granted_qos))
def unsubscribe(client, userdata, topic, pid):
# This method is called when the client unsubscribes from a feed.
print('Unsubscribed from {0} with PID {1}'.format(topic, pid))
# pylint: disable=unused-argument
def disconnected(client):
# Disconnected function will be called when the client disconnects.
print("Disconnected from Adafruit IO!")
# pylint: disable=unused-argument
def message(client, feed_id, payload):
# Message function will be called when a subscribed feed has a new value.
# The feed_id parameter identifies the feed, and the payload parameter has
# the new value.
print("Feed {0} received new value: {1}".format(feed_id, payload))
# Connect to WiFi
wifi.connect()
# Initialize a new MQTT Client object
mqtt_client = MQTT(
socket=socket,
broker="io.adafruit.com",
username=secrets["aio_username"],
password=secrets["aio_key"],
network_manager=wifi
)
# Initialize an Adafruit IO MQTT Client
io = IO_MQTT(mqtt_client)
# Connect the callback methods defined above to Adafruit IO
io.on_connect = connected
io.on_disconnect = disconnected
io.on_subscribe = subscribe
io.on_unsubscribe = unsubscribe
io.on_message = message
# Connect to Adafruit IO
io.connect()
# Below is an example of manually publishing a new value to Adafruit IO.
last = 0
print("Publishing a new message every 10 seconds...")
while True:
# Explicitly pump the message loop.
io.loop()
# Send a new message every 10 seconds.
if (time.monotonic() - last) >= 5:
value = randint(0, 100)
print("Publishing {0} to DemoFeed.".format(value))
io.publish("DemoFeed", value)
last = time.monotonic()
# You can also call loop_blocking if you only want to receive values.
# NOTE: If uncommented, no code below this line will run.
# io.loop_blocking()