micropython-lib/micropython/bluetooth/aioble/examples/l2cap_file_client.py

140 wiersze
3.8 KiB
Python

# MIT license; Copyright (c) 2021 Jim Mussared
# This is a WIP client for l2cap_file_server.py. See that file for more
# information.
import sys
sys.path.append("")
from micropython import const
import uasyncio as asyncio
import aioble
import bluetooth
import random
import struct
_FILE_SERVICE_UUID = bluetooth.UUID(0x1234)
_CONTROL_CHARACTERISTIC_UUID = bluetooth.UUID(0x1235)
_COMMAND_SEND = const(0)
_COMMAND_RECV = const(1) # Not yet implemented.
_COMMAND_LIST = const(2)
_COMMAND_SIZE = const(3)
_COMMAND_DONE = const(4)
_STATUS_OK = const(0)
_STATUS_NOT_IMPLEMENTED = const(1)
_STATUS_NOT_FOUND = const(2)
_L2CAP_PSN = const(22)
_L2CAP_MTU = const(128)
class FileClient:
def __init__(self, device):
self._device = device
self._connection = None
self._seq = 1
async def connect(self):
try:
print("Connecting to", self._device)
self._connection = await self._device.connect()
except asyncio.TimeoutError:
print("Timeout during connection")
return
try:
print("Discovering...")
file_service = await self._connection.service(_FILE_SERVICE_UUID)
self._control_characteristic = await file_service.characteristic(
_CONTROL_CHARACTERISTIC_UUID
)
except asyncio.TimeoutError:
print("Timeout discovering services/characteristics")
return
print("Connecting channel")
self._channel = await self._connection.l2cap_connect(_L2CAP_PSN, _L2CAP_MTU)
async def _command(self, cmd, data):
send_seq = self._seq
await self._control_characteristic.write(struct.pack("<BB", cmd, send_seq) + data)
self._seq += 1
return send_seq
async def size(self, path):
print("Getting size")
send_seq = await self._command(_COMMAND_SIZE, path.encode())
data = await self._control_characteristic.notified()
if len(data) != 6:
raise RuntimeError("Invalid response")
seq, status, size = struct.unpack("<BBI", data)
if seq != send_seq:
raise RuntimeError("Wrong reply")
print("result:", seq, status, size)
return size
async def download(self, path, dest):
size = await self.size(path)
send_seq = await self._command(_COMMAND_SEND, path.encode())
with open(dest, "wb") as f: # noqa: ASYNC101
total = 0
buf = bytearray(self._channel.our_mtu)
mv = memoryview(buf)
while total < size:
n = await self._channel.recvinto(buf)
f.write(mv[:n])
total += n
async def list(self, path):
send_seq = await self._command(_COMMAND_LIST, path.encode())
results = bytearray()
buf = bytearray(self._channel.our_mtu)
mv = memoryview(buf)
while True:
n = await self._channel.recvinto(buf)
results += mv[:n]
if results[len(results) - 1] == ord("\n") and results[len(results) - 2] == ord("\n"):
break
print(results.decode().split("\n"))
async def disconnect(self):
if self._connection:
await self._connection.disconnect()
async def main():
async with aioble.scan(5000, 30000, 30000, active=True) as scanner:
async for result in scanner:
if result.name() == "mpy-file" and _FILE_SERVICE_UUID in result.services():
device = result.device
break
else:
print("File server not found")
return
client = FileClient(device)
await client.connect()
print(await client.size("demo/file.txt"))
print(await client.size("demo/notfound.bin"))
await client.download("demo/file.txt", "download.txt")
await client.list("demo")
await client.disconnect()
asyncio.run(main())