Can't get web page to run asynchronously on ESP32 with Micropython

[SilverNodashi]

I am trying to run a web page asynchronously on an ESP32 using MicroPython. Along with the webpage, which will allow me to turn a relay on, on demand, I want to run a timed function which turns the relay on, every morning at 08:00.

I am using an ESP32 Dev board with CP2102 USB chip, DS1307 RTC and 5V relay.

When I run the code in the REPL, I can see the "run_relay_timer(), but none of the other debugging output

The web server debugging output is not showing either, nor can I connect to http://192.168.10.130/ (the DHCP IP assigned to this ESP32)

Looking at the REPL in Thonny, the run_rrelay_timer() runs, but not the run_web_page()

`import asyncio

import esp
esp.osdebug(None)

import time
import urtc
from machine import I2C, Pin

set_hour = 15
set_time = 30

relay = Pin(4, Pin.OUT)
led = Pin(2, Pin.OUT)
relay.value(0) # Start OFF (active low)

def web_page():
if relay.value() == 0:
print("Relay value: ")
print(relay.value)
relay_state = ''
else:
relay_state = 'checked'
html = """<style>
body{font-family:Arial; text-align: center; margin: 0px auto; padding-top:30px;}
.switch{position:relative;display:inline-block;width:120px;height:68px}.switch input{display:none}
.slider{position:absolute;top:0;left:0;right:0;bottom:0;background-color:#ccc;border-radius:34px}
.slider:before{position:absolute;content:"";height:52px;width:52px;left:8px;bottom:8px;background-color:#fff;-webkit-transition:.4s;transition:.4s;border-radius:68px}
input:checked+.slider{background-color:#2196F3}
input:checked+.slider:before{-webkit-transform:translateX(52px);-ms-transform:translateX(52px);transform:translateX(52px)}
</style><script>function toggleCheckbox(element) { var xhr = new XMLHttpRequest(); if(element.checked){ xhr.open("GET", "/?relay=on", true); }
else { xhr.open("GET", "/?relay=off", true); } xhr.send(); }</script>

Sprinkler control

""" % (relay_state) return html

s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind(('', 80))
s.listen(5)

Define coroutine function

async def run_relay_timer():
while True:
print('run_relay_timer()') # Debugging output
import time
import urtc
from machine import I2C, Pin

    set_hour = 8
    set_time = 30

    relay = Pin(4, Pin.OUT)
    led = Pin(2, Pin.OUT)
    relay.value(0)  # Start OFF (active low)

    days_of_week = ['Maandag', 'Dinsdag', 'Woensdag', 'Donderdag', 'Vrydag', 'Saterdag', 'Sondag']

# Initialize RTC (connected to I2C) - ESP32
i2c = I2C(0, scl=Pin(22), sda=Pin(21))
rtc = urtc.DS3231(i2c)

current_datetime = rtc.datetime()
temperature = rtc.get_temperature()
# Format the date and time
formatted_datetime = (
   f"{days_of_week[current_datetime.weekday]}, "
   f"{current_datetime.year:04d}-{current_datetime.month:02d}-{current_datetime.day:02d} "
   f"{current_datetime.hour:02d}:{current_datetime.minute:02d}:{current_datetime.second:02d} "
)

current_datetime = rtc.datetime()
 
  # Display time details
  #print('Current date and time:')
  #print('Year:', current_datetime.year)
  #print('Month:', current_datetime.month)
  #print('Day:', current_datetime.day)
  #print('Hour:', current_datetime.hour)
  #print('Minute:', current_datetime.minute)
  #print('Second:', current_datetime.second)
  #print('Day of the Week:', days_of_week[current_datetime.weekday])
  #print(f"Current temperature: {temperature}°C")    
    # Format the date and time
formatted_datetime = (
     f"{days_of_week[current_datetime.weekday]}, "
     f"{current_datetime.year:04d}-{current_datetime.month:02d}-{current_datetime.day:02d} "
     f"{current_datetime.hour:02d}:{current_datetime.minute:02d}:{current_datetime.second:02d} "
)
#print(f"Current date and time: {formatted_datetime}")

if current_datetime.hour != set_hour:
    print('Dit is nog nie' ,set_hour,'uur nie') # Debugging output
    print('Die tyd is',formatted_datetime) # Debugging output
    led.value(0)
    relay.value(0)

if current_datetime.hour == set_hour:
    print('Die tyd is',formatted_datetime)  # Debugging output
    if current_datetime.minute < set_time:
      led.value(1)
      relay.value(1)
      print('Sit besproeing pomp aan vir',set_time,'minute') # Debugging output
      print(" \n"); # Debugging output
else:
    led.value(0)
    relay.value(0)
    print('Die besproeing het vir',set_time,'minute gehardloop') # Debugging output
    print(" \n"); # Debugging output
 
#time.sleep(1)
await asyncio.sleep(1)

async def run_web_page():
while True:
print('run_web_page()') # Debugging output
try:
if gc.mem_free() < 102000:
gc.collect()
conn, addr = s.accept()
conn.settimeout(3.0)
print('Got a connection from %s' % str(addr)) # Debugging output
request = conn.recv(1024)
conn.settimeout(None)
request = str(request)

  print('Content = %s' % request)
  relay_on = request.find('/?relay=on')
  relay_off = request.find('/?relay=off')
  if relay_on == 6:
    print('RELAY ON')
    relay.value(1)
    led.value(1)
  if relay_off == 6:
    print('RELAY OFF')
    relay.value(0)
    led.value(0)
       
  response = web_page()
  conn.send('HTTP/1.1 200 OK\n')
  conn.send('Content-Type: text/html\n')
  conn.send('Connection: close\n\n')
  conn.sendall(response)
  conn.close()
except OSError as e:
  conn.close()
  print('Connection closed')
  await asyncio.sleep(0.5)

Define the main function to run the event loop

async def main():
# Create tasks for blinking two LEDs concurrently
asyncio.create_task(run_relay_timer())
asyncio.create_task(run_web_page())

Create and run the event loop

loop = asyncio.get_event_loop()
loop.create_task(main()) # Create a task to run the main function
loop.run_forever() # Run the event loop indefinitely
`

[peterhinch]

Please see this post and read the paragraph on code formatting. Follow the guidelines to preserve indenting.

There is an approved asynchronous web framework: microdot.

I've not studied your code in detail, but this function (assuming I've guessed your indentation correctly) will stall the scheduler and prevent other tasks from running:

async def run_relay_timer():
    while True:
        print('run_relay_timer()') # Debugging output

[SilverNodashi]

I am still new to Python and Micropython programming.

Why would this function stall the scheduler?

[ricksorensen]

It does not return control to the asyncio scheduler so it will run the synchronous while True: loop forever. I needs a handoff back to the scheduler. For example:

while True:
    print("something")
    await asyncio.sleep(1)       # return to scheduler to allow other tasks to run.

[sosi-deadeye]

I guess it's something else. time.sleep is commented out.

Please fix the formatting. Here the trick with changing <div> to <pre> doesn't work. Here are too many <p>aragraphs.