Ruby binding for bluez Profile API
this gem allows easy creation of bluetooth services. For example create a serial link over to another device using bluetooth.
https://github.com/pauloborges/bluez/blob/master/doc/profile-api.txt
Clive Andrews 2021
dependencies
- Linux/Unix type system
- bluez 5
- glib-2 (dev)
prerequisites
your bluetooth devices must be paired and trusted outside of this gem in order for them to communicate.
use eg bluetoothctl
install
gem install bluez-profile
API
example code:
class MyProfile < Bluez::Profile
# This method gets called when the service daemon
# unregisters the profile. A profile can use it to do
# cleanup tasks.
def release
end
# This method gets called when a new service level
# connection has been made and authorized.
def connection(device, fd, fd_properties)
end
# This method gets called when a profile gets
# disconnected.
#
# The file descriptor is no longer owned by the service
# daemon and the profile implementation needs to take
# care of cleaning up all connections.
#
# If multiple file descriptors are indicated via
# NewConnection, it is expected that all of them
# are disconnected before returning from this
# method call.
def disconnection(device)
end
end
path = '/my/dbus/path'
uuid = '1101'
options = {
name: 'my profile',
channel: 3
connect: false
}
profile = MyProfile.new(path, uuid, options)
profile.run # enters loop and blocks here.
profile.stop # stops the loop
path: string
the dbus object path of the profile.
eg: "/serial/special/profile"
uuid: string
the dbus profile uuid
Available options:
name: string
Human readable name for the profile
service: string
The primary service class UUID
(if different from the actual
profile UUID)
role: string
For asymmetric profiles that do not
have UUIDs available to uniquely
identify each side this
parameter allows specifying the
precise local role.
Possible values:
Bluez::Profile::Client
Bluez::Profile::Server
channel: int
RFCOMM channel number that is used
for client and server UUIDs.
If applicable it will be used in the
SDP record as well.
psm: int
PSM number that is used for client
and server UUIDs.
If applicable it will be used in the
SDP record as well.
authentication: boolean
Pairing is required before connections
will be established. No devices will
be connected if not paired.
authorization: boolean
Request authorization before any
connection will be established.
connect: boolean
In case of a client UUID this will
force connection of the RFCOMM or
L2CAP channels when a remote device
is connected.
record: string
Provide a manual SDP record.
version: int
Profile version (for SDP record)
features: int
Profile features (for SDP record)
server
If a channel number is already in use your service may not be registered. Check that your services have been registered correctly with eg:
sudo sdptool browse local
examples
See the /examples folder.
issues
The server side of things seems to work fine.
run several servers over the same serial service using different channel numbers
on the client ( paired and trusted) connect each channel eg :
sudo rfcomm connect /dev/rfcomm0 remoteaddr channel1
sudo rfcomm connect /dev/rfcomm1 remoteaddr channel2
sudo rfcomm connect /dev/rfcomm2 remoteaddr channel3
this works perfectly. each device file allows interaction with the correct server.
BUT if on the client a profile is registered with bluez using this gem and a connection made to the server then things get in a muddle and output for the one channel gets sent to the wrong profile !!
any ideas ??