def __init__(self, hci_device='hci0', gatttool_logfile=None,
cli_options=None, search_window_size=None, max_read=None):
"""
Initialize.
hci_device -- the hci_device to use with GATTTool.
gatttool_logfile -- an optional filename to store raw gatttool
input and output.
search_window_size -- integer (optional); size in bytes of the
search window that is used by `pexpect.expect`. This value
should not exceed max_read
max_read -- integer; number of bytes to read into gatt buffer at
a time. Defaults to ~2000
"""
if is_windows():
raise BLEError("The GATTToolBackend requires BlueZ, "
"which is not available in Windows")
self._hci_device = hci_device
self._cli_options = cli_options
self._connected_device = None
self._gatttool_logfile = gatttool_logfile
self._receiver = None
self._con = None # gatttool interactive session
self._characteristics = {}
self._running = threading.Event()
self._address = None
self._send_lock = threading.Lock()
self._auto_reconnect = False
self._reconnecting = False
self._search_window_size = search_window_size
self._scan = None
self._max_read = max_read
def __init__(self,
hci_device='hci0',
gatttool_logfile=None,
cli_options=None,
search_window_size=200):
"""
Initialize.
hci_device -- the hci_device to use with GATTTool.
gatttool_logfile -- an optional filename to store raw gatttool
input and output.
search_window_size -- integer (optional); size in bytes of the
search window that is used by `pexpect.expect`
"""
if is_windows():
raise BLEError("The GATTToolBackend requires BlueZ, "
"which is not available in Windows")
self._hci_device = hci_device
self._cli_options = cli_options
self._connected_device = None
self._gatttool_logfile = gatttool_logfile
self._receiver = None
self._con = None # gatttool interactive session
self._characteristics = {}
self._running = threading.Event()
self._address = None
self._send_lock = threading.Lock()
self._search_window_size = search_window_size
def scan(self, timeout=10, run_as_root=False):
"""
By default, scanning with gatttool requires root privileges.
If you don't want to require root, you must add a few
'capabilities' to your system. If you have libcap installed, run this to
enable normal users to perform LE scanning:
setcap 'cap_net_raw,cap_net_admin+eip' `which hcitool`
If you do use root, the hcitool subprocess becomes more difficult to
terminate cleanly, and may leave your Bluetooth adapter in a bad state.
"""
cmd = 'hcitool lescan'
if run_as_root:
cmd = 'sudo %s' % cmd
log.info("Starting BLE scan")
scan = pexpect.spawn(cmd)
# "lescan" doesn't exit, so we're forcing a timeout here:
try:
scan.expect('foooooo', timeout=timeout)
except pexpect.EOF:
message = "Unexpected error when scanning"
if "No such device" in scan.before.decode('utf-8'):
message = "No BLE adapter found"
log.error(message)
raise BLEError(message)
except pexpect.TIMEOUT:
devices = {}
for line in scan.before.decode('utf-8').split('\r\n'):
match = re.match(
r'(([0-9A-Fa-f][0-9A-Fa-f]:?){6}) (\(?[\w]+\)?)', line)
if match is not None:
address = match.group(1)
name = match.group(3)
if name == "(unknown)":
name = None
if address in devices:
if (devices[address]['name'] is None) and (name is not
None):
log.info("Discovered name of %s as %s",
address, name)
devices[address]['name'] = name
else:
log.info("Discovered %s (%s)", address, name)
devices[address] = {
'address': address,
'name': name
}
log.info("Found %d BLE devices", len(devices))
return [device for device in devices.values()]
return []
def scan(self, timeout=10, run_as_root=False):
"""
By default, scanning with gatttool requires root privileges.
If you don't want to require root, you must add a few
'capabilities' to your system. If you have libcap installed, run this to
enable normal users to perform LE scanning:
setcap 'cap_net_raw,cap_net_admin+eip' `which hcitool`
If you do use root, the hcitool subprocess becomes more difficult to
terminate cleanly, and may leave your Bluetooth adapter in a bad state.
"""
cmd = 'hcitool -i %s lescan' % self._hci_device
if run_as_root:
cmd = 'sudo %s' % cmd
log.info("Starting BLE scan")
scan = pexpect.spawn(cmd)
# "lescan" doesn't exit, so we're forcing a timeout here:
try:
scan.expect('foooooo', timeout=timeout)
except pexpect.EOF:
before_eof = scan.before.decode('utf-8')
if "No such device" in before_eof:
message = "No BLE adapter found"
elif "Set scan parameters failed: Input/output error" in before_eof:
message = ("BLE adapter requires reset after a scan as root"
"- call adapter.reset()")
else:
message = "Unexpected error when scanning: %s" % before_eof
log.error(message)
raise BLEError(message)
except pexpect.TIMEOUT:
devices = {}
for line in scan.before.decode('utf-8').split('\r\n'):
if 'sudo' in line:
raise BLEError("Enable passwordless sudo for 'hcitool' "
"before scanning")
match = re.match(
r'(([0-9A-Fa-f][0-9A-Fa-f]:?){6}) (\(?.+\)?)', line)
if match is not None:
address = match.group(1)
name = match.group(3)
if name == "(unknown)":
name = None
if address in devices:
if (devices[address]['name'] is None) and (name is not
None):
log.info("Discovered name of %s as %s",
address, name)
devices[address]['name'] = name
else:
log.info("Discovered %s (%s)", address, name)
devices[address] = {
'address': address,
'name': name
}
log.info("Found %d BLE devices", len(devices))
return [device for device in devices.values()]
finally:
# Wait for lescan to exit cleanly, otherwise it leaves the BLE
# adapter in a bad state and the device must be reset through BlueZ.
# This will not work if run_as_root was used, since this process
# itself doesn't have permission to terminate a process running as
# root (hcitool itself). We recommend using the setcap tool to allow
# scanning as a non-root user:
#
# $ sudo setcap 'cap_net_raw,cap_net_admin+eip' `which hcitool`
try:
scan.kill(signal.SIGINT)
scan.wait()
except OSError:
log.error("Unable to gracefully stop the scan - "
"BLE adapter may need to be reset.")
return []
def scan(self, timeout=10, run_as_root=False):
"""
By default, scanning with gatttool requires root privileges.
If you don't want to require root, you must add a few
'capabilities' to your system. If you have libcap installed, run this to
enable normal users to perform LE scanning:
setcap 'cap_net_raw,cap_net_admin+eip' `which hcitool`
If you do use root, the hcitool subprocess becomes more difficult to
terminate cleanly, and may leave your Bluetooth adapter in a bad state.
"""
cmd = 'hcitool -i %s lescan' % self._hci_device
if run_as_root and which('sudo') != None:
cmd = 'sudo %s' % cmd
log.info("Starting BLE scan")
# "lescan" doesn't exit, so we're forcing a timeout
self._scan = scan = pexpect.spawn(cmd, timeout=timeout)
try:
scan.expect('foooooo')
except pexpect.EOF:
before_eof = scan.before.decode('utf-8', 'replace')
if "No such device" in before_eof:
message = "No BLE adapter found"
elif "Set scan parameters failed: Input/output error" in before_eof:
message = ("BLE adapter requires reset after a scan as root"
"- call adapter.reset()")
else:
message = "Unexpected error when scanning: %s" % before_eof
log.error(message)
raise BLEError(message)
except pexpect.TIMEOUT:
devices = {}
for line in scan.before.decode('utf-8', 'replace').split('\r\n'):
if 'sudo' in line:
raise BLEError("Enable passwordless sudo for 'hcitool' "
"before scanning")
match = re.match(r'(([0-9A-Fa-f][0-9A-Fa-f]:?){6}) (\(?.+\)?)',
line)
if match is not None:
address = match.group(1)
name = match.group(3)
if name == "(unknown)":
name = None
if address in devices:
if (devices[address]['name'] is
None) and (name is not None):
log.info("Discovered name of %s as %s", address,
name)
devices[address]['name'] = name
else:
log.info("Discovered %s (%s)", address, name)
devices[address] = {'address': address, 'name': name}
log.info("Found %d BLE devices", len(devices))
return [device for device in devices.values()]
finally:
self.kill()
return []