`dasbus.error.DBusError: No valid service object found` from Bluez - bluetooth-lowenergy

Question

I've run out of ideas on how to debug this... I'm attempting to implement a Bluetooth Low Energy Peripheral in Python, and keep getting this error:
dasbus.error.DBusError: No valid service object found
Here's what's happening on sudo dbus-monitor --system "destination='org.bluez'" "sender='org.bluez'"
method call time=1638075250.607870 sender=:1.45928 -> destination=org.bluez serial=2 path=/org/bluez/hci0; interface=org.freedesktop.DBus.Introspectable; member=Introspect
method return time=1638075250.608574 sender=:1.5 -> destination=:1.45928 serial=1663 reply_serial=2
string "<!DOCTYPE node PUBLIC "-//freedesktop//DTD D-BUS Object Introspection 1.0//EN"
"http://www.freedesktop.org/standards/dbus/1.0/introspect.dtd">
<node><interface name="org.freedesktop.DBus.Introspectable"><method name="Introspect"><arg name="xml" type="s" direction="out"/>
</method></interface><interface name="org.bluez.Adapter1"><method name="StartDiscovery"></method><method name="SetDiscoveryFilter"><arg name="properties" type="a{sv}" direction="in"/>
</method><method name="StopDiscovery"></method><method name="RemoveDevice"><arg name="device" type="o" direction="in"/>
</method><method name="GetDiscoveryFilters"><arg name="filters" type="as" direction="out"/>
</method><property name="Address" type="s" access="read"></property><property name="AddressType" type="s" access="read"></property><property name="Name" type="s" access="read"></property><property name="Alias" type="s" access="readwrite"></property><property name="Class" type="u" access="read"></property><property name="Powered" type="b" access="readwrite"></property><property name="Discoverable" type="b" access="readwrite"></property><property name="DiscoverableTimeout" type="u" access="readwrite"></property><property name="Pairable" type="b" access="readwrite"></property><property name="PairableTimeout" type="u" access="readwrite"></property><property name="Discovering" type="b" access="read"></property><property name="UUIDs" type="as" access="read"></property><property name="Modalias" type="s" access="read"></property></interface><interface name="org.freedesktop.DBus.Properties"><method name="Get"><arg name="interface" type="s" direction="in"/>
<arg name="name" type="s" direction="in"/>
<arg name="value" type="v" direction="out"/>
</method><method name="Set"><arg name="interface" type="s" direction="in"/>
<arg name="name" type="s" direction="in"/>
<arg name="value" type="v" direction="in"/>
</method><method name="GetAll"><arg name="interface" type="s" direction="in"/>
<arg name="properties" type="a{sv}" direction="out"/>
</method><signal name="PropertiesChanged"><arg name="interface" type="s"/>
<arg name="changed_properties" type="a{sv}"/>
<arg name="invalidated_properties" type="as"/>
</signal>
</interface><interface name="org.bluez.GattManager1"><method name="RegisterApplication"><arg name="application" type="o" direction="in"/>
<arg name="options" type="a{sv}" direction="in"/>
</method><method name="UnregisterApplication"><arg name="application" type="o" direction="in"/>
</method></interface><interface name="org.bluez.LEAdvertisingManager1"><method name="RegisterAdvertisement"><arg name="advertisement" type="o" direction="in"/>
<arg name="options" type="a{sv}" direction="in"/>
</method><method name="UnregisterAdvertisement"><arg name="service" type="o" direction="in"/>
</method><property name="ActiveInstances" type="y" access="read"></property><property name="SupportedInstances" type="y" access="read"></property><property name="SupportedIncludes" type="as" access="read"></property></interface><interface name="org.bluez.Media1"><method name="RegisterEndpoint"><arg name="endpoint" type="o" direction="in"/>
<arg name="properties" type="a{sv}" direction="in"/>
</method><method name="UnregisterEndpoint"><arg name="endpoint" type="o" direction="in"/>
</method><method name="RegisterPlayer"><arg name="player" type="o" direction="in"/>
<arg name="properties" type="a{sv}" direction="in"/>
</method><method name="UnregisterPlayer"><arg name="player" type="o" direction="in"/>
</method></interface><interface name="org.bluez.NetworkServer1"><method name="Register"><arg name="uuid" type="s" direction="in"/>
<arg name="bridge" type="s" direction="in"/>
</method><method name="Unregister"><arg name="uuid" type="s" direction="in"/>
</method></interface></node>"
method call time=1638075250.617093 sender=:1.45928 -> destination=org.bluez serial=3 path=/org/bluez/hci0; interface=org.freedesktop.DBus.Properties; member=Set
string "org.bluez.Adapter1"
string "Powered"
variant boolean true
method return time=1638075250.617637 sender=:1.5 -> destination=:1.45928 serial=1664 reply_serial=3
method call time=1638075250.619644 sender=:1.45928 -> destination=org.bluez serial=4 path=/org/bluez/hci0; interface=org.freedesktop.DBus.Properties; member=Get
string "org.bluez.Adapter1"
string "Powered"
method return time=1638075250.620197 sender=:1.5 -> destination=:1.45928 serial=1665 reply_serial=4
variant boolean true
method call time=1638075250.627078 sender=:1.45928 -> destination=org.bluez serial=5 path=/org/bluez/hci0; interface=org.bluez.LEAdvertisingManager1; member=RegisterAdvertisement
object path "/com/ah/Biofeedback/Advertisement/1"
array [
]
method call time=1638075250.627809 sender=:1.5 -> destination=org.freedesktop.DBus serial=1666 path=/org/freedesktop/DBus; interface=org.freedesktop.DBus; member=AddMatch
string "type='signal',sender='org.freedesktop.DBus',path='/org/freedesktop/DBus',interface='org.freedesktop.DBus',member='NameOwnerChanged',arg0=':1.45928'"
method return time=1638075250.627870 sender=org.freedesktop.DBus -> destination=:1.5 serial=1174 reply_serial=1666
method call time=1638075250.628483 sender=:1.5 -> destination=org.freedesktop.DBus serial=1667 path=/org/freedesktop/DBus; interface=org.freedesktop.DBus; member=GetNameOwner
string ":1.45928"
method return time=1638075250.628534 sender=org.freedesktop.DBus -> destination=:1.5 serial=1175 reply_serial=1667
string ":1.45928"
method call time=1638075250.628903 sender=:1.5 -> destination=org.freedesktop.DBus serial=1668 path=/org/freedesktop/DBus; interface=org.freedesktop.DBus; member=AddMatch
string "type='signal',sender=':1.45928',path='/com/ah/Biofeedback/Advertisement/1',interface='org.freedesktop.DBus.ObjectManager',member='InterfacesAdded'"
method return time=1638075250.628958 sender=org.freedesktop.DBus -> destination=:1.5 serial=1176 reply_serial=1668
method call time=1638075250.629497 sender=:1.5 -> destination=org.freedesktop.DBus serial=1669 path=/org/freedesktop/DBus; interface=org.freedesktop.DBus; member=AddMatch
string "type='signal',sender=':1.45928',path='/com/ah/Biofeedback/Advertisement/1',interface='org.freedesktop.DBus.ObjectManager',member='InterfacesRemoved'"
method return time=1638075250.629572 sender=org.freedesktop.DBus -> destination=:1.5 serial=1177 reply_serial=1669
method call time=1638075250.629875 sender=:1.5 -> destination=org.freedesktop.DBus serial=1670 path=/org/freedesktop/DBus; interface=org.freedesktop.DBus; member=AddMatch
string "type='signal',sender=':1.45928',path_namespace='/com/ah/Biofeedback/Advertisement/1'"
method return time=1638075250.629928 sender=org.freedesktop.DBus -> destination=:1.5 serial=1178 reply_serial=1670
method call time=1638075250.630459 sender=:1.5 -> destination=org.freedesktop.DBus serial=1671 path=/org/freedesktop/DBus; interface=org.freedesktop.DBus; member=AddMatch
string "type='signal',sender=':1.45928',path='/com/ah/Biofeedback/Advertisement/1',interface='org.freedesktop.DBus.Properties',member='PropertiesChanged',arg0='org.bluez.LEAdvertisement1'"
method return time=1638075250.630517 sender=org.freedesktop.DBus -> destination=:1.5 serial=1179 reply_serial=1671
method call time=1638075250.631390 sender=:1.5 -> destination=org.freedesktop.DBus serial=1672 path=/org/freedesktop/DBus; interface=org.freedesktop.DBus; member=StartServiceByName
string ":1.45928"
uint32 0
error time=1638075250.631460 sender=org.freedesktop.DBus -> destination=:1.5 error_name=org.freedesktop.DBus.Error.ServiceUnknown reply_serial=1672
string "The name :1.45928 was not provided by any .service files"
method call time=1638075250.631553 sender=:1.5 -> destination=:1.45928 serial=1673 path=/com/ah/Biofeedback/Advertisement/1; interface=org.freedesktop.DBus.ObjectManager; member=GetManagedObjects
error time=1638075250.632629 sender=:1.45928 -> destination=:1.5 error_name=org.freedesktop.DBus.Error.UnknownMethod reply_serial=1673
string "No such interface “org.freedesktop.DBus.ObjectManager” on object at path /com/ah/Biofeedback/Advertisement/1"
method call time=1638075250.632916 sender=:1.5 -> destination=:1.45928 serial=1674 path=/com/ah/Biofeedback/Advertisement/1; interface=org.freedesktop.DBus.Properties; member=GetAll
string "org.bluez.LEAdvertisement1"
method return time=1638075250.639601 sender=:1.45928 -> destination=:1.5 serial=7 reply_serial=1674
array [
dict entry(
string "Appearance"
variant uint16 768
)
dict entry(
string "Discoverable"
variant boolean true
)
dict entry(
string "DiscoverableTimeout"
variant uint16 10000
)
dict entry(
string "LocalName"
variant string "AH Biofeedback Device"
)
dict entry(
string "ServiceUUIDS"
variant array [
string "what"
]
)
dict entry(
string "Type"
variant string "peripheral"
)
]
signal time=1638075250.641071 sender=:1.5 -> destination=(null destination) serial=1675 path=/org/bluez/hci0; interface=org.freedesktop.DBus.Properties; member=PropertiesChanged
string "org.bluez.LEAdvertisingManager1"
array [
dict entry(
string "SupportedInstances"
variant byte 4
)
dict entry(
string "ActiveInstances"
variant byte 1
)
]
array [
]
method return time=1638075250.641346 sender=:1.5 -> destination=:1.45928 serial=1676 reply_serial=5
method call time=1638075250.649537 sender=:1.45928 -> destination=org.bluez serial=8 path=/org/bluez/hci0; interface=org.bluez.GattManager1; member=RegisterApplication
object path "/com/ah/Biofeedback/Application/1"
array [
]
method call time=1638075250.649994 sender=:1.5 -> destination=org.freedesktop.DBus serial=1677 path=/org/freedesktop/DBus; interface=org.freedesktop.DBus; member=GetNameOwner
string ":1.45928"
method return time=1638075250.650051 sender=org.freedesktop.DBus -> destination=:1.5 serial=1181 reply_serial=1677
string ":1.45928"
method call time=1638075250.650459 sender=:1.5 -> destination=org.freedesktop.DBus serial=1678 path=/org/freedesktop/DBus; interface=org.freedesktop.DBus; member=AddMatch
string "type='signal',sender=':1.45928',path='/com/ah/Biofeedback/Application/1',interface='org.freedesktop.DBus.ObjectManager',member='InterfacesAdded'"
method return time=1638075250.650515 sender=org.freedesktop.DBus -> destination=:1.5 serial=1182 reply_serial=1678
method call time=1638075250.651102 sender=:1.5 -> destination=org.freedesktop.DBus serial=1679 path=/org/freedesktop/DBus; interface=org.freedesktop.DBus; member=AddMatch
string "type='signal',sender=':1.45928',path='/com/ah/Biofeedback/Application/1',interface='org.freedesktop.DBus.ObjectManager',member='InterfacesRemoved'"
method return time=1638075250.651159 sender=org.freedesktop.DBus -> destination=:1.5 serial=1183 reply_serial=1679
method call time=1638075250.651590 sender=:1.5 -> destination=org.freedesktop.DBus serial=1680 path=/org/freedesktop/DBus; interface=org.freedesktop.DBus; member=AddMatch
string "type='signal',sender=':1.45928',path_namespace='/com/ah/Biofeedback/Application/1'"
method return time=1638075250.651646 sender=org.freedesktop.DBus -> destination=:1.5 serial=1184 reply_serial=1680
method call time=1638075250.651759 sender=:1.5 -> destination=:1.45928 serial=1681 path=/com/ah/Biofeedback/Application/1; interface=org.freedesktop.DBus.ObjectManager; member=GetManagedObjects
method return time=1638075250.659644 sender=:1.45928 -> destination=:1.5 serial=9 reply_serial=1681
array [
dict entry(
object path "/com/ah/Biofeedback/Service/1"
array [
dict entry(
string "org.bluez.GattService1"
array [
dict entry(
string "UUID"
variant string "service-uuid-abc"
)
dict entry(
string "Primary"
variant boolean true
)
dict entry(
string "Characteristics"
variant array [
object path "/com/ah/Biofeedback/Characteristic/1"
]
)
]
)
]
)
dict entry(
object path "/com/ah/Biofeedback/Characteristic/1"
array [
dict entry(
string "org.bluez.GattCharacteristic1"
array [
dict entry(
string "Service"
variant object path "/com/ah/Biofeedback/Service/1"
)
dict entry(
string "UUID"
variant string "characteristic-uuid-abc"
)
dict entry(
string "Flags"
variant array [
string "broadcast"
]
)
dict entry(
string "Descriptors"
variant array [
]
)
]
)
]
)
]
method call time=1638075250.660665 sender=:1.5 -> destination=org.freedesktop.DBus serial=1682 path=/org/freedesktop/DBus; interface=org.freedesktop.DBus; member=AddMatch
string "type='signal',sender=':1.45928',path='/com/ah/Biofeedback/Service/1',interface='org.freedesktop.DBus.Properties',member='PropertiesChanged',arg0='org.bluez.GattService1'"
method return time=1638075250.660724 sender=org.freedesktop.DBus -> destination=:1.5 serial=1185 reply_serial=1682
method call time=1638075250.663350 sender=:1.5 -> destination=org.freedesktop.DBus serial=1683 path=/org/freedesktop/DBus; interface=org.freedesktop.DBus; member=AddMatch
string "type='signal',sender=':1.45928',path='/com/ah/Biofeedback/Characteristic/1',interface='org.freedesktop.DBus.Properties',member='PropertiesChanged',arg0='org.bluez.GattCharacteristic1'"
method return time=1638075250.663436 sender=org.freedesktop.DBus -> destination=:1.5 serial=1186 reply_serial=1683
error time=1638075250.663466 sender=:1.5 -> destination=:1.45928 error_name=org.bluez.Error.Failed reply_serial=8
string "No valid service object found"
method call time=1638075250.663509 sender=:1.5 -> destination=org.freedesktop.DBus serial=1685 path=/org/freedesktop/DBus; interface=org.freedesktop.DBus; member=RemoveMatch
string "type='signal',sender=':1.45928',path_namespace='/com/ah/Biofeedback/Application/1'"
method return time=1638075250.663556 sender=org.freedesktop.DBus -> destination=:1.5 serial=1187 reply_serial=1685
method call time=1638075250.663584 sender=:1.5 -> destination=org.freedesktop.DBus serial=1686 path=/org/freedesktop/DBus; interface=org.freedesktop.DBus; member=RemoveMatch
string "type='signal',sender=':1.45928',path='/com/ah/Biofeedback/Service/1',interface='org.freedesktop.DBus.Properties',member='PropertiesChanged',arg0='org.bluez.GattService1'"
method return time=1638075250.663634 sender=org.freedesktop.DBus -> destination=:1.5 serial=1188 reply_serial=1686
method call time=1638075250.663663 sender=:1.5 -> destination=org.freedesktop.DBus serial=1687 path=/org/freedesktop/DBus; interface=org.freedesktop.DBus; member=RemoveMatch
string "type='signal',sender=':1.45928',path='/com/ah/Biofeedback/Characteristic/1',interface='org.freedesktop.DBus.Properties',member='PropertiesChanged',arg0='org.bluez.GattCharacteristic1'"
method return time=1638075250.663712 sender=org.freedesktop.DBus -> destination=:1.5 serial=1189 reply_serial=1687
method call time=1638075250.663827 sender=:1.5 -> destination=org.freedesktop.DBus serial=1688 path=/org/freedesktop/DBus; interface=org.freedesktop.DBus; member=RemoveMatch
string "type='signal',sender=':1.45928',path='/com/ah/Biofeedback/Application/1',interface='org.freedesktop.DBus.ObjectManager',member='InterfacesAdded'"
method return time=1638075250.663880 sender=org.freedesktop.DBus -> destination=:1.5 serial=1190 reply_serial=1688
method call time=1638075250.664064 sender=:1.5 -> destination=org.freedesktop.DBus serial=1689 path=/org/freedesktop/DBus; interface=org.freedesktop.DBus; member=RemoveMatch
string "type='signal',sender=':1.45928',path='/com/ah/Biofeedback/Application/1',interface='org.freedesktop.DBus.ObjectManager',member='InterfacesRemoved'"
method return time=1638075250.664119 sender=org.freedesktop.DBus -> destination=:1.5 serial=1191 reply_serial=1689
Here's my code:
from dasbus.connection import SystemMessageBus
from dasbus.typing import *
from dasbus.server.interface import dbus_interface
from dasbus.server.interface import dbus_signal
from dasbus.server.publishable import Publishable
from dasbus.server.template import InterfaceTemplate
from dasbus.loop import EventLoop
from threading import Thread
#dbus_interface("org.bluez.LEAdvertisement1")
class BiofeedackAdvertisement(object):
def Release(self) -> None:
print("released")
#property
def Type(self) -> Str:
return "peripheral"
#property
def ServiceUUIDS(self) -> List[Str]:
return ["what"]
#property
def Discoverable(self) -> Bool:
return True
#property
def DiscoverableTimeout(self) -> UInt16:
return 10000
#property
def LocalName(self) -> Str:
return "AH Biofeedback Device"
# https://specificationrefs.bluetooth.com/assigned-values/Appearance%20Values.pdf
#property
def Appearance(self) -> UInt16:
return 768 # Thermometer
# path: "/com/ah/Biofeedback/Application/1"
class Application(Publishable):
def for_publication(self):
return ApplicationInterface(self)
#dbus_interface("org.bluez.GattApplication1")
class ApplicationGattInterface(InterfaceTemplate):
pass
#dbus_interface("org.freedesktop.DBus.ObjectManager")
class ApplicationInterface(ApplicationGattInterface):
def GetManagedObjects(self) -> Dict[ObjPath, Dict[Str, Dict[Str, Variant]]]:
return {
"/com/ah/Biofeedback/Service/1": ServiceInterface(Service()).get_properties(),
"/com/ah/Biofeedback/Characteristic/1": CharacteristicInterface(Characteristic()).get_properties(),
# "/com/ah/Biofeedback/Descriptor/1": Descriptor().get_properties(),
}
class Service(Publishable):
def for_publication(self):
return ServiceInterface(self)
# Not sure if this is being used, but it's not the problem right now.
#dbus_interface("org.freedesktop.DBus.Properties")
class ServiceInterfaceProperties(InterfaceTemplate):
#dbus_signal
def PropertiesChanged(self, interface: Str, changed_properties: Dict[Str, Variant], invalidated_properties: List[Str]):
print("PROPS CHANGED")
pass
def GetAll(self, interface: Str) -> Dict[Str, Variant]:
print("GETALL")
return self.get_properties()["org.bluez.GattService1"]
#dbus_interface("org.bluez.GattService1")
class ServiceInterfaceGatt(InterfaceTemplate):
#property
def UUID(self) -> Str:
return "service-uuid-abc"
#property
def Primary(self) -> Bool:
return True
# path: /com/ah/Biofeedback/Service/1
class ServiceInterface(ServiceInterfaceGatt, ServiceInterfaceProperties):
_UUID = Variant("s", "service-uuid-abc")
def get_properties(self):
return {
"org.bluez.GattService1": {
"UUID": self._UUID,
"Primary": Variant("b", True),
"Characteristics": Variant.new_array(None, [Variant("o", "/com/ah/Biofeedback/Characteristic/1")]),
}
}
class Characteristic(Publishable):
def for_publication(self):
return CharacteristicInterface(self)
#dbus_interface("org.bluez.GattCharacteristic1")
class CharacteristicInterfaceGatt(InterfaceTemplate):
def ReadValue(self, options: Dict[Str, Str]) -> List[Byte]:
print("TRIED TO READ VALUE")
return [0xDEAD]
def WriteValue(self, value: List[Byte], options: Dict[Str, Str]) -> None:
print("TRIED TO WRITE VALUE")
pass
#property
def UUID(self) -> Str:
return "characteristic-uuid-abc"
#property
def Service(self) -> ObjPath:
return "/com/ah/Biofeedback/Service/1"
# path: /com/ah/Biofeedback/Characteristic/1
class CharacteristicInterface(CharacteristicInterfaceGatt):
_UUID = Variant("s", "characteristic-uuid-abc")
def get_properties(self):
return {
"org.bluez.GattCharacteristic1": {
"Service": Variant("s", "/com/ah/Biofeedback/Service/1"),
"UUID": self._UUID,
"Flags": Variant.new_array(None, [Variant("s", "broadcast")]),
#"Descriptors": Variant.new_array(None, [Variant("o", "/com/ah/Biofeedback/Descriptor/1")]),
"Descriptors": Variant.new_array(VariantType("t"), []),
}
}
# path: /com/ah/Biofeedback/Descriptor/1
# #dbus_interface("org.bluez.GattDescriptor1")
class Descriptor(object):
_UUID = Variant("s", "descriptor-uuid-1vc")
def get_properties(self):
return {
"org.bluez.GattDescriptor1": {
"Characteristic": Variant("s", "/com/ah/Biofeedback/Characteristic/1"),
"UUID": self._UUID,
"Flags": Variant.new_array(VariantType("t"), []),
}
}
def main():
bus = SystemMessageBus()
Thread(target=EventLoop().run).start()
bus.register_service("com.ah.Biofeedback")
proxy = bus.get_proxy("org.bluez", "/org/bluez/hci0")
proxy.Set("org.bluez.Adapter1", "Powered", Variant("b", True))
print(proxy.Get("org.bluez.Adapter1", "Powered"))
advertisementPath = "/com/ah/Biofeedback/Advertisement/1"
bus.publish_object(advertisementPath, BiofeedackAdvertisement())
proxy.RegisterAdvertisement(advertisementPath, {})
bus.publish_object("/com/ah/Biofeedback/Service/1", Service().for_publication())
bus.publish_object("/com/ah/Biofeedback/Characteristic/1", Characteristic().for_publication())
appPath = "/com/ah/Biofeedback/Application/1"
bus.publish_object(appPath, Application().for_publication())
proxy.RegisterApplication(appPath, {})
if __name__ == '__main__':
main()
It looks like the Service is registered on the bus:
sudo dbus-send --system --print-reply \
> --dest=:1.46935 \
> /com/ah/Biofeedback/Service/1 \
> org.freedesktop.DBus.Introspectable.Introspect
method return time=1638120479.547238 sender=:1.13051 -> destination=:1.13060 serial=12 reply_serial=2
string "<!DOCTYPE node PUBLIC "-//freedesktop//DTD D-BUS Object Introspection 1.0//EN"
"http://www.freedesktop.org/standards/dbus/1.0/introspect.dtd">
<!-- GDBus 2.58.3 -->
<node>
<interface name="org.freedesktop.DBus.Properties">
<method name="Get">
<arg type="s" name="interface_name" direction="in"/>
<arg type="s" name="property_name" direction="in"/>
<arg type="v" name="value" direction="out"/>
</method>
<method name="GetAll">
<arg type="s" name="interface_name" direction="in"/>
<arg type="a{sv}" name="properties" direction="out"/>
</method>
<method name="Set">
<arg type="s" name="interface_name" direction="in"/>
<arg type="s" name="property_name" direction="in"/>
<arg type="v" name="value" direction="in"/>
</method>
<signal name="PropertiesChanged">
<arg type="s" name="interface_name"/>
<arg type="a{sv}" name="changed_properties"/>
<arg type="as" name="invalidated_properties"/>
</signal>
</interface>
<interface name="org.freedesktop.DBus.Introspectable">
<method name="Introspect">
<arg type="s" name="xml_data" direction="out"/>
</method>
</interface>
<interface name="org.freedesktop.DBus.Peer">
<method name="Ping"/>
<method name="GetMachineId">
<arg type="s" name="machine_uuid" direction="out"/>
</method>
</interface>
<interface name="org.bluez.GattService1">
<property type="b" name="Primary" access="read">
</property>
<property type="s" name="UUID" access="read">
</property>
</interface>
</node>
"
/var/log/syslog gives a little clue:
bluetoothd[22894]: Failed to read "UUID" property of service
bluetoothd[22894]: Failed to add service
bluetoothd[22894]: Failed to create GATT service entry in local database
The dependencies were a pain to setup, so here's a docker container:
docker run -it --rm \
--privileged \
--workdir /app \
--volume "$PWD":/app \
--volume /var/run/dbus/:/var/run/dbus/:z \
soodesune/python3-bluetooth dbus-bluetooth.py
What else can I do to debug this error? How can I figure out what's wrong with my Service UUID?

Answer 1

Figured it out! There was a long list of small problems that I had to work through. Here's the process that I followed to debug:
Run sudo dbus-monitor --system "destination='org.bluez'" "sender='org.bluez'" to see what Bluez is sending/receiving from dbus
Watch /var/log/syslog to see what errors Bluez is logging, but /not/ sending to dbus
Download the source code for your version of Bluez
Run your program
Then:
Make sure the traffic on dbus looks right
When you see errors in /var/log/syslog grep the source code for the error and see what went wrong. Most of the time there was type-checking logic that I wasn't satisfying. For example: the UUIDs have some pretty specific checks, and I had a few Object Path types mis-coded as String.
Keep looping through those steps until you've got it working.
I did a really through writeup of using Bluetooth, D-Bus, BlueZ on a Raspberry Pi at raspberrypi-bluetooth.com