Unable to connect to Kuksa databroker server

[TheLittleNaruto]

Hi

I am trying Kuksa python SDK to connect to kuksa databroker. However it fails to connect.

Steps which I followed:

To start the databroker server:

tln@tln-X550LD:~/Kuksa$ sudo docker run -it --rm --name Server --network kuksa ghcr.io/eclipse-kuksa/kuksa-databroker:main --insecure
[sudo] password for tln: 
2024-06-16T12:35:01.443571Z  INFO databroker: Init logging from RUST_LOG (environment variable not found)
2024-06-16T12:35:01.443589Z  INFO databroker: Starting Kuksa Databroker 0.4.6
2024-06-16T12:35:01.444322Z  INFO databroker: Populating metadata from file 'vss_release_4.0.json'
2024-06-16T12:35:01.726938Z  WARN databroker: Authorization is not enabled.
2024-06-16T12:35:01.727027Z  INFO databroker::broker: Starting housekeeping task
2024-06-16T12:35:01.727055Z  INFO databroker::grpc::server: Listening on 0.0.0.0:55555
2024-06-16T12:35:01.727065Z  INFO databroker::grpc::server: TLS is not enabled
2024-06-16T12:35:01.727073Z  INFO databroker::grpc::server: Authorization is not enabled.

To verify the connect, ran the databroker-cli

tln@tln-X550LD:~/Kuksa$ sudo docker run -it --rm --network kuksa ghcr.io/eclipse-kuksa/kuksa-databroker-cli:main --server Server:55555
Using kuksa.val.v1

  ⠀⠀⠀⢀⣤⣶⣾⣿⢸⣿⣿⣷⣶⣤⡀
  ⠀⠀⣴⣿⡿⠋⣿⣿⠀⠀⠀⠈⠙⢿⣿⣦⠀
  ⠀⣾⣿⠋⠀⠀⣿⣿⠀⠀⣶⣿⠀⠀⠙⣿⣷   
  ⣸⣿⠇⠀⠀⠀⣿⣿⠠⣾⡿⠃⠀⠀⠀⠸⣿⣇⠀⠀⣶⠀⣠⡶⠂⠀⣶⠀⠀⢰⡆⠀⢰⡆⢀⣴⠖⠀⢠⡶⠶⠶⡦⠀⠀⠀⣰⣶⡀
  ⣿⣿⠀⠀⠀⠀⠿⢿⣷⣦⡀⠀⠀⠀⠀⠀⣿⣿⠀⠀⣿⢾⣏⠀⠀⠀⣿⠀⠀⢸⡇⠀⢸⡷⣿⡁⠀⠀⠘⠷⠶⠶⣦⠀⠀⢠⡟⠘⣷
  ⢹⣿⡆⠀⠀⠀⣿⣶⠈⢻⣿⡆⠀⠀⠀⢰⣿⡏⠀⠀⠿⠀⠙⠷⠄⠀⠙⠷⠶⠟⠁⠀⠸⠇⠈⠻⠦⠀⠐⠷⠶⠶⠟⠀⠠⠿⠁⠀⠹⠧
  ⠀⢿⣿⣄⠀⠀⣿⣿⠀⠀⠿⣿⠀⠀⣠⣿⡿
  ⠀⠀⠻⣿⣷⡄⣿⣿⠀⠀⠀⢀⣠⣾⣿⠟    databroker-cli                
  ⠀⠀⠀⠈⠛⠇⢿⣿⣿⣿⣿⡿⠿⠛⠁     v0.4.6                        

Successfully connected to http://Server:55555/
kuksa.val.v1 > publish Vehicle.Speed 42
[publish]  OK  
kuksa.val.v1 > get Vehicle.Speed
[get]  OK  
Vehicle.Speed: 42.00 km/h
kuksa.val.v1 > 

As we can see, it is able to publish to the databroker and get it back.

Now used kuksa python sdk to achieve the same:

tln@tln-X550LD:~/Kuksa/trying-kuksa-python-sdk$ python3 -m venv env
tln@tln-X550LD:~/Kuksa/trying-kuksa-python-sdk$ source env/bin/activate
(env) tln@tln-X550LD:~/Kuksa/trying-kuksa-python-sdk$ pip install kuksa-client

Now ran the kuksa-client command

(env) tln@tln-X550LD:~/Kuksa/trying-kuksa-python-sdk$ kuksa-client

But this resulted in below error:

     ⢀⣤⣶⣾⣿⢸⣿⣿⣷⣶⣤⡀
    ⣴⣿⡿⠋⣿⣿   ⠈⠙⢿⣿⣦
   ⣾⣿⠋  ⣿⣿  ⣶⣿  ⠙⣿⣷
  ⣸⣿⠇   ⣿⣿⠠⣾⡿⠃   ⠸⣿⣇  ⣶ ⣠⡶⠂ ⣶  ⢰⡆ ⢰⡆⢀⣴⠖ ⢠⡶⠶⠶⡦   ⣰⣶⡀
  ⣿⣿    ⠿⢿⣷⣦⡀     ⣿⣿  ⣿⢾⣏   ⣿  ⢸⡇ ⢸⡷⣿⡁  ⠘⠷⠶⠶⣦  ⢠⡟⠘⣷
  ⢹⣿⡆   ⣿⣶⠈⢻⣿⡆   ⢰⣿⡏  ⠿ ⠙⠷⠄ ⠙⠷⠶⠟⠁ ⠸⠇⠈⠻⠦ ⠐⠷⠶⠶⠟ ⠠⠿⠁ ⠹⠧
   ⢿⣿⣄  ⣿⣿  ⠿⣿  ⣠⣿⡿
    ⠻⣿⣷⡄⣿⣿   ⢀⣠⣾⣿⠟    kuksa-client CLI
     ⠈⠛⠇⢿⣿⣿⣿⣿⡿⠿⠛⠁     0.4.3


Connecting to VSS server at 127.0.0.1 port 55555 using KUKSA GRPC protocol.
TLS will not be used.
2024-06-16 17:59:41,321 INFO kuksa_client.grpc: No Root CA present, it will not be possible to use a secure connection!
2024-06-16 17:59:41,321 INFO kuksa_client.grpc.aio: Establishing insecure channel
Exception in thread Thread-1:
Traceback (most recent call last):
  File "/home/tln/Kuksa/trying-kuksa-python-sdk/env/lib/python3.11/site-packages/kuksa_client/grpc/aio.py", line 386, in get_server_info
    resp = await self.client_stub.GetServerInfo(req, **rpc_kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/tln/Kuksa/trying-kuksa-python-sdk/env/lib/python3.11/site-packages/grpc/aio/_call.py", line 318, in __await__
    raise _create_rpc_error(
grpc.aio._call.AioRpcError: <AioRpcError of RPC that terminated with:
	status = StatusCode.UNAVAILABLE
	details = "failed to connect to all addresses; last error: UNKNOWN: ipv4:127.0.0.1:55555: Failed to connect to remote host: Connection refused"
	debug_error_string = "UNKNOWN:Error received from peer  {created_time:"2024-06-16T17:59:41.323376945+05:30", grpc_status:14, grpc_message:"failed to connect to all addresses; last error: UNKNOWN: ipv4:127.0.0.1:55555: Failed to connect to remote host: Connection refused"}"
>

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "/usr/lib/python3.11/threading.py", line 1045, in _bootstrap_inner
    self.run()
  File "/home/tln/Kuksa/trying-kuksa-python-sdk/env/lib/python3.11/site-packages/kuksa_client/__init__.py", line 118, in run
    self.loop.run_until_complete(self.backend.mainLoop())
  File "/usr/lib/python3.11/asyncio/base_events.py", line 653, in run_until_complete
    return future.result()
           ^^^^^^^^^^^^^^^
  File "/home/tln/Kuksa/trying-kuksa-python-sdk/env/lib/python3.11/site-packages/kuksa_client/cli_backend/grpc.py", line 276, in mainLoop
    async with kuksa_client.grpc.aio.VSSClient(self.serverIP, self.serverPort, token=self.token) as vss_client:
  File "/home/tln/Kuksa/trying-kuksa-python-sdk/env/lib/python3.11/site-packages/kuksa_client/grpc/aio.py", line 61, in __aenter__
    await self.connect()
  File "/home/tln/Kuksa/trying-kuksa-python-sdk/env/lib/python3.11/site-packages/kuksa_client/grpc/aio.py", line 87, in connect
    logger.debug("Connected to server: %s", await self.get_server_info())
                                            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/tln/Kuksa/trying-kuksa-python-sdk/env/lib/python3.11/site-packages/kuksa_client/grpc/aio.py", line 102, in wrapper
    return await func(self, *args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/tln/Kuksa/trying-kuksa-python-sdk/env/lib/python3.11/site-packages/kuksa_client/grpc/aio.py", line 393, in get_server_info
    raise VSSClientError.from_grpc_error(exc) from exc
kuksa_client.grpc.VSSClientError: ({'code': 14, 'reason': 'unavailable', 'message': 'failed to connect to all addresses; last error: UNKNOWN: ipv4:127.0.0.1:55555: Failed to connect to remote host: Connection refused'}, [])
Error: Websocket could not be connected or the gRPC channel could not be created.
2024-06-16 17:59:47,321 INFO kuksa_client.cli_backend.grpc: gRPC channel disconnected.

Could you please help what went wrong here? BTW I also tried to manually connect to databroker, by running below command:

Test Client> connect http://Server:55555
Invalid server URI. Unsupported protocol: http

And it did not work, but same command works on Kuksa databroker-cli.

[wba2hi]

Can you try again to connect using kuksa-client grpc://Server:55555 (instead of http://Server:55555)?

Kuksa-Client supports two different protocols, where each uses a custom URI format. On one hand the protocol grpc:// to establish a connection using gRPC and on the other hand ws:// to establish a connection using Websockets. In case TLS is being used it is grpcs://...and wss://

[TheLittleNaruto]

Can you try again to connect using kuksa-client grpc://Server:55555 (instead of http://Server:55555)?

Kuksa-Client supports two different protocols, where each uses a custom URI format. On one hand the protocol grpc:// to establish a connection using gRPC and on the other hand ws:// to establish a connection using Websockets. In case TLS is being used it is grpcs://...and wss://

I tried both of them, but same error. @wba2hi

[SebastianSchildt]

Can you double check, whether the error is the same, because the original error message said, it does not recognize http, so if you replacaed that with e.g. grpc:// I would at least expect a different error

[SebastianSchildt]

Also you used a docker network "kuksa", are you sure this is reachable from "outside" (because you use venv directly on host for client). I think at least under Linux this may require some routing being set up.

A simple way to test is, instead of using a custom network, use host mode in docker, i.e. start

sudo docker run -it --rm --name Server --net=host ghcr.io/eclipse-kuksa/kuksa-databroker:main --insecure

And then try connecting wiht kuksa-client again (using the IP or hostname of your computer)

[thu4n]

I actually had the same error with StatusCode.UNAVAILABLE when using the SDK. I managed to fix this by downgrading the Kuksa Databroker version to 0.4.4 instead of the latest version.