[esp8266_micropython] 使用mqtt协议控制esp8266nodemuc的led

mao_jin_dao · 发表于 2023-6-5 23:40:35

本帖最后由 mao_jin_dao 于 2023-6-5 23:46 编辑

本贴使用mqtt协议控制esp8266板子上的led灯，为后续控制继电器做功能验证。

软硬件准备： mosquitto(mqtt 服务器), 刷有micropython固件的esp8266。
安装mosquitto
<pre>
# linux环境shell操作如下
apt install mosquitto-dev
echo "port 1883" >> /etc/mosquitto/mosquitto.conf
echo "protocol mqtt" >> /etc/mosquitto/mosquitto.conf
echo "allow_anonymous yes" >> /etc/mosquitto/mosquitto.conf
systemctl start mosquitto
systemctl enable mosquitto
</pre>

ESP8266代码如下，代码结构请参考图片
main.py
<pre>

import umqtt.simple import MQTTClient
import urequests as requests
import network
from machine import Pin
import time
import ujson

led=Pin(2,Pin.OUT)

def connectionWifi(ssid, password):
  wlan = network.WLAN(network.STA_IF)
  wlan.active(True)
  wlan.connect(ssid, password)
  while True:
if not wlan.isconnected():
   time.sleep_ms(2000)
else:
   print('connected to network')
   led.off()
   break

def sub_callback(topic, msg):
  msgStr = msg.decode()
  print(msgStr)
  print(msgStr.replace('\"','\''))
  msgObj = ujson.loads(msgStr)
  if(msgObj['target_esp'] != mqttClientId):
print("not the device")
return
  print(msgObj['led_status'])
  if(msgObj['led_status'] == "on"):
led.off()
  elif(msgObj['led_status'] == "off"):
led.on()
  else:
print("unknow led's status "+msgObj['led_status'])

if __name__== '__main__':
  ssid='FAST_20CC'
  password='409409409'

  mqttServerIP='192.168.1.113'
  mqttServerPort=1883
  mqttClientId='esp0001'
  mqttSubTopic=b'espiot'

  connectionWifi(ssid, password)

  client = MQTTClient(mqttClientId, mqttServerIP, mqttServerPort)
  client.set_callback(sub_callback)
  client.connect()
  print('mqtt client connected')
  client.subscribe(mqttSubTopic)
  while True:
client.wait_msg()

</pre>

simple.py
<pre>

# simple.py
import usocket as socket
import ustruct as struct
#from ubinascii import hexlify

class MQTTException(Exception):
pass

class MQTTClient:

  def __init__(self, client_id, server, port=0, user=None, password=None, keepalive=0,ssl=False, ssl_params={}):
if port == 0:
   port = 8883 if ssl else 1883
self.client_id = client_id
self.sock = None
self.addr = socket.getaddrinfo(server, port)[0][-1]
self.ssl = ssl
self.ssl_params = ssl_params
self.pid = 0
self.cb = None
self.user = user
self.pswd = password
self.keepalive = keepalive
self.lw_topic = None
self.lw_msg = None
self.lw_qos = 0
self.lw_retain = False

  def _send_str(self, s):
self.sock.write(struct.pack("!H", len(s)))
self.sock.write(s)

  def _recv_len(self):
n = 0
sh = 0
while 1:
   b = self.sock.read(1)[0]
   n |= (b & 0x7f) << sh
   if not b & 0x80:
      return n
   sh += 7

  def set_callback(self, f):
self.cb = f

  def set_last_will(self, topic, msg, retain=False, qos=0):
assert 0 <= qos <= 2
assert topic
self.lw_topic = topic
self.lw_msg = msg
self.lw_qos = qos
self.lw_retain = retain

  def connect(self, clean_session=True):
self.sock = socket.socket()
self.sock.connect(self.addr)
if self.ssl:
   import ussl
   self.sock = ussl.wrap_socket(self.sock, **self.ssl_params)
msg = bytearray(b"\x10\0\0\x04MQTT\x04\x02\0\0")
msg[1] = 10 + 2 + len(self.client_id)
msg[9] = clean_session << 1
if self.user is not None:
   msg[1] += 2 + len(self.user) + 2 + len(self.pswd)
   msg[9] |= 0xC0
if self.keepalive:
   assert self.keepalive < 65536
   msg[10] |= self.keepalive >> 8
   msg[11] |= self.keepalive & 0x00FF
if self.lw_topic:
   msg[1] += 2 + len(self.lw_topic) + 2 + len(self.lw_msg)
   msg[9] |= 0x4 | (self.lw_qos & 0x1) << 3 | (self.lw_qos & 0x2) << 3
   msg[9] |= self.lw_retain << 5
self.sock.write(msg)
#print(hex(len(msg)), hexlify(msg, ":"))
self._send_str(self.client_id)
if self.lw_topic:
   self._send_str(self.lw_topic)
   self._send_str(self.lw_msg)
if self.user is not None:
   self._send_str(self.user)
   self._send_str(self.pswd)
resp = self.sock.read(4)
assert resp[0] == 0x20 and resp[1] == 0x02
if resp[3] != 0:
   raise MQTTException(resp[3])
return resp[2] & 1

  def disconnect(self):
self.sock.write(b"\xe0\0")
self.sock.close()

  def ping(self):
self.sock.write(b"\xc0\0")

  def publish(self, topic, msg, retain=False, qos=0):
pkt = bytearray(b"\x30\0\0\0")
pkt[0] |= qos << 1 | retain
sz = 2 + len(topic) + len(msg)
if qos > 0:
   sz += 2
assert sz < 2097152
i = 1
while sz > 0x7f:
   pkt = (sz & 0x7f) | 0x80
   sz >>= 7
   i += 1
pkt = sz
#print(hex(len(pkt)), hexlify(pkt, ":"))
self.sock.write(pkt, i + 1)
self._send_str(topic)
if qos > 0:
   self.pid += 1
   pid = self.pid
   struct.pack_into("!H", pkt, 0, pid)
   self.sock.write(pkt, 2)
self.sock.write(msg)
if qos == 1:
   while 1:
      op = self.wait_msg()
      if op == 0x40:
      sz = self.sock.read(1)
      assert sz == b"\x02"
      rcv_pid = self.sock.read(2)
      rcv_pid = rcv_pid[0] << 8 | rcv_pid[1]
      if pid == rcv_pid:
         return
elif qos == 2:
   assert 0

  def subscribe(self, topic, qos=0):
assert self.cb is not None, "Subscribe callback is not set"
pkt = bytearray(b"\x82\0\0\0")
self.pid += 1
struct.pack_into("!BH", pkt, 1, 2 + 2 + len(topic) + 1, self.pid)
#print(hex(len(pkt)), hexlify(pkt, ":"))
self.sock.write(pkt)
self._send_str(topic)
self.sock.write(qos.to_bytes(1, "little"))
while 1:
   op = self.wait_msg()
   if op == 0x90:
      resp = self.sock.read(4)
      #print(resp)
      assert resp[1] == pkt[2] and resp[2] == pkt[3]
      if resp[3] == 0x80:
      raise MQTTException(resp[3])
      return

  # Wait for a single incoming MQTT message and process it.
  # Subscribed messages are delivered to a callback previously
  # set by .set_callback() method. Other (internal) MQTT
  # messages processed internally.
  def wait_msg(self):
res = self.sock.read(1)
self.sock.setblocking(True)
if res is None:
   return None
if res == b"":
   raise OSError(-1)
if res == b"\xd0":  # PINGRESP
   sz = self.sock.read(1)[0]
   assert sz == 0
   return None
op = res[0]
if op & 0xf0 != 0x30:
   return op
sz = self._recv_len()
topic_len = self.sock.read(2)
topic_len = (topic_len[0] << 8) | topic_len[1]
topic = self.sock.read(topic_len)
sz -= topic_len + 2
if op & 6:
   pid = self.sock.read(2)
   pid = pid[0] << 8 | pid[1]
   sz -= 2
msg = self.sock.read(sz)
self.cb(topic, msg)
if op & 6 == 2:
   pkt = bytearray(b"\x40\x02\0\0")
   struct.pack_into("!H", pkt, 2, pid)
   self.sock.write(pkt)
elif op & 6 == 4:
   assert 0

  # Checks whether a pending message from server is available.
  # If not, returns immediately with None. Otherwise, does
  # the same processing as wait_msg.
  def check_msg(self):
self.sock.setblocking(False)
return self.wait_msg()

</pre>

使用mosquitto_pub及mqttx进行测试