From 1be9a52f11d7bb9cf519c6ee8027c9029824e29c Mon Sep 17 00:00:00 2001 From: Erg Date: Mon, 21 Oct 2024 17:02:14 +0200 Subject: Comment change --- umqttsimple.py | 214 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 214 insertions(+) create mode 100644 umqttsimple.py (limited to 'umqttsimple.py') 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 -- cgit v1.2.3-65-gdbad