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| author | Erg <uinarf@autistici.org> | 2024-10-21 17:02:14 +0200 |
|---|---|---|
| committer | Erg <uinarf@autistici.org> | 2024-10-21 17:02:14 +0200 |
| commit | 1be9a52f11d7bb9cf519c6ee8027c9029824e29c (patch) | |
| tree | a71b0edf5c4748000a8f5515dd215a9052ef927e /umqttsimple.py | |
| download | Pico-1be9a52f11d7bb9cf519c6ee8027c9029824e29c.tar.gz Pico-1be9a52f11d7bb9cf519c6ee8027c9029824e29c.tar.bz2 Pico-1be9a52f11d7bb9cf519c6ee8027c9029824e29c.zip | |
Comment change
Diffstat (limited to 'umqttsimple.py')
| -rw-r--r-- | umqttsimple.py | 214 |
1 files changed, 214 insertions, 0 deletions
diff --git a/umqttsimple.py b/umqttsimple.py new file mode 100644 index 0000000..44d1dde --- /dev/null +++ b/umqttsimple.py @@ -0,0 +1,214 @@ +import usocket as socket
+import ustruct as struct
+
+
+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.server = server
+ self.port = port
+ 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()
+ addr = socket.getaddrinfo(self.server, self.port)[0][-1]
+ self.sock.connect(addr)
+ if self.ssl:
+ import ussl
+
+ self.sock = ussl.wrap_socket(self.sock, **self.ssl_params)
+ premsg = bytearray(b"\x10\0\0\0\0\0")
+ msg = bytearray(b"\x04MQTT\x04\x02\0\0")
+
+ sz = 10 + 2 + len(self.client_id)
+ msg[6] = clean_session << 1
+ if self.user is not None:
+ sz += 2 + len(self.user) + 2 + len(self.pswd)
+ msg[6] |= 0xC0
+ if self.keepalive:
+ assert self.keepalive < 65536
+ msg[7] |= self.keepalive >> 8
+ msg[8] |= self.keepalive & 0x00FF
+ if self.lw_topic:
+ sz += 2 + len(self.lw_topic) + 2 + len(self.lw_msg)
+ msg[6] |= 0x4 | (self.lw_qos & 0x1) << 3 | (self.lw_qos & 0x2) << 3
+ msg[6] |= self.lw_retain << 5
+
+ i = 1
+ while sz > 0x7F:
+ premsg[i] = (sz & 0x7F) | 0x80
+ sz >>= 7
+ i += 1
+ premsg[i] = sz
+
+ self.sock.write(premsg, i + 2)
+ 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[i] = (sz & 0x7F) | 0x80
+ sz >>= 7
+ i += 1
+ pkt[i] = 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()
\ No newline at end of file |