kuksa-client 0.3.0

kuksa.val python clients and SDK

Kuksa Client

kuksa.val is a part of the opensource project eclipse kuksa. More about kuksa.val can be found in the repository.

Introduction

kuksa-client provides both a command-line interface (CLI) and a standalone library to interact with either KUKSA.val server or KUKSA databroker.

Installing the client and starting its CLI

The fastest way to start using kuksa-client is to install a pre-built version from pypi.org:

$ pip install kuksa-client

If you want to install from sources instead see Building and running a local version.

After you have installed the kuksa-client package via pip you can run the test client CLI directly by executing:

$ kuksa-client

With default CLI arguments, the client will try to connect to a local VISS server e.g. kuksa-val-server. If you wish to connect to a gRPC server e.g. kuksa-databroker, you should instead run:

$ kuksa-client --ip 127.0.0.1 --port 55555 --protocol grpc --insecure

Note: --insecure is required because kuksa-databroker does not yet support encryption or authentication.

If everything works as expected and the server can be contacted you will get an output similar to below.

Welcome to Kuksa Client version <some_version>

                  `-:+o/shhhs+:`
                ./oo/+o/``.-:ohhs-
              `/o+-  /o/  `..  :yho`
              +o/    /o/  oho    ohy`
             :o+     /o/`+hh.     sh+
             +o:     /oo+o+`      /hy
             +o:     /o+/oo-      +hs
             .oo`    oho `oo-    .hh:
              :oo.   oho  -+:   -hh/
               .+o+-`oho     `:shy-
                 ./o/ohy//+oyhho-
                    `-/+oo+/:.

Default tokens directory: /some/path/kuksa_certificates/jwt

connectj to wss://127.0.0.1:8090
Websocket connected securely.
Test Client>

The next step is to authorize against the server. The jwt tokens for testing can either be found under kuksa_certificates/jwt or you can also use following command inside kuksa-client to find the via pip installed certificate directory.

Test Client> printTokenDir

Select one of the tokens and use the authorize command like below.

Test Client> authorize /some/path/kuksa_certificates/jwt/super-admin.json.token

Usage Instructions

Refer help for further information

VSS Client> help -v

Documented commands (use 'help -v' for verbose/'help <topic>' for details):

Communication Set-up Commands
================================================================================
authorize           Authorize the client to interact with the server
connect
disconnect          Disconnect from the VSS Server
getServerAddress    Gets the IP Address for the VSS Server
setServerAddress    Sets the IP Address for the VSS Server

Info Commands
================================================================================
info                Show summary info of the client
printTokenDir       Show token directory
version             Show version of the client

Kuksa Interaction Commands
================================================================================
getMetaData         Get MetaData of the path
getValue            Get the value of a path
setValue            Set the value of a path
updateMetaData      Update MetaData of a given path
updateVSSTree      Update VSS Tree Entry

This is an example showing how some of the commands can be used:

Updating VSS Structure

Using the testclient, it is also possible to update and extend the VSS data structure. More details can be found here.

Note: You can also use setValue to change the value of an array, but the value should not contains any non-quoted spaces. Consider the following examples:

Test Client> setValue Vehicle.OBD.DTCList ["dtc1","dtc2"]
{
    "action": "set",
    "requestId": "f7b199ce-4d86-4759-8d9a-d6f8f935722d",
    "ts": "2022-03-22T17:19:34.1647965974Z"
}

Test Client> setValue Vehicle.OBD.DTCList '["dtc1", "dtc2"]'
{
    "action": "set",
    "requestId": "d4a19322-67d8-4fad-aa8a-2336404414be",
    "ts": "2022-03-22T17:19:44.1647965984Z"
}

Test Client> setValue Vehicle.OBD.DTCList ["dtc1", "dtc2"]
usage: setValue [-h] Path Value
setValue: error: unrecognized arguments: dtc2 ]

Building and running a local version

For development purposes it may be necessary to customize the code for the client and run a locally built version. First we suggest you create a dedicated python virtual environment for kuksa-client:

$ mkdir --parents ~/.venv
$ python3 -m venv ~/.venv/kuksa-client
$ source ~/.venv/kuksa-client/bin/activate  # Run this every time you want to activate kuksa-client's virtual environment
(kuksa-client) $ pip install --upgrade pip

Now in order to ensure local *.py files will be used when running the client, we need to install kuksa-client in editable mode:

(kuksa-client) $ pip install -r requirements.txt -e .

If you wish to also install test dependencies, run instead:

(kuksa-client) $ pip install -r test-requirements.txt -e ".[test]"

If you ever wish to upgrade provided requirements, see Requirements.

Now you should be able to start using kuksa-client:

(kuksa-client) $ kuksa-client --help

Whenever you want to exit kuksa-client's virtual environment, simply run:

(kuksa-client) $ deactivate
$

Using Docker

You can build a docker image of the testclient using the Dockerfile. Not the most effcient way to pack a small python script, but it is easy to get started. The Dockerfile needs to be executed on the parent directory (so it include the needed certificates and pip package configuration).

$ cd /some/dir/kuksa.val
$ docker build -f kuksa-client/Dockerfile -t kuksa-client:latest .

To run the newly built image:

$ docker run --rm -it --net=host kuksa-client:latest --help

Notes:

• --rm ensures we do not keep the docker container lying around after closing kuksa-client and --net=host makes sure you can reach locally running kuksa.val-server or kuksa-val docker with port forwarding on the host using the default 127.0.0.1 address.
• CLI arguments that follow image name (e.g. kuksa-client:latest) will be passed through to kuksa-client entry point (e.g. --help).

Running test suite & quality checks

This project uses pytest as its test framework and pylint as its linter. To run the test suite:

$ pytest

To run the linter:

$ pylint kuksa_client

Python library

kuksa-client also provides a library to allow you to develop your own application that interacts with either kuksa-val-server or kuksa_databroker.

Usage

Import library's main package.

>>> import kuksa_client
>>> kuksa_client.__version__
'<your version, e.g. 0.1.7>'

This package holds different APIs depending on your application's requirements. For more information, see (Documentation).

Troubleshooting

1. The server/data broker is listening on its port but my client is unable to connect to it and returns an error:

Error: Websocket could not be connected or the gRPC channel could not be created.

If you're running both client and server on your local host, make sure that:

• localhost domain name resolution is configured properly on your host.
• You are not using any proxies for localhost e.g. setting the no_proxy environment variable to localhost,127.0.0.1.
• If you are using the gRPC protocol in secure mode, the server certificate should have CN = localhost in its subject.

2. ImportError: cannot import name 'types_pb2' from 'kuksa.val.v1': It sometimes happens that _pb2*.py files are not generated on editable installations of kuksa_client. In order to manually generate those files and get more details if anything fails, run:

python setup.py build_pb2