Fix errors in examples

[erikbosch]

I performed the following test:

• Cloning https://github.com/eclipse-velocitas/vehicle-app-python-template
• Adapting it to use the SDK from #139
• For each example in this repo, copy the manifest file and source to the template app folder
• Do "velocitas init", start local runtime and then try to start the app.
• Example-specific instructions NOT followed.

What I fixed:

• Complaints on velocitas init (except VSS version missmatch)
• Python errors when trying to start app (typicall sdv_modelnot found)

What I did not fix:

• App business logic inconsistencies and runtime errors, like that some examples uses VSS 4.1 but tooling use unit file from 4.0?

[erikbosch]

IMO if we now do some fixes on the examples we should align everything, that means we should use VSS 4.0 everywhere and also adapt the datapoints accordingly.

Furthermore we should align the structure to have a main and vapp file as in the seat-adjuster example.

If we don't do it correct IMO this PR is not helping a lot, since we still need additional work...

How is it as of today? Is Databroker always started with default VSS catalog when starting runtime, i.e. not considering what is written in appManifest? If so it makes sense to adapt examples so they all use default VSS version. I did this work mostly to validate that there are no regressions coming from #139 which does not seem to be the case, if we are to verify/update all aspects of each example more time would be needed.

It also appears to me that many examples are quite similar, so do we need them all? If we would pend more time on them it would also be great if they could be tested as part of CI when updating SDK. That does not happen today, right?

[MP91]

IMO if we now do some fixes on the examples we should align everything, that means we should use VSS 4.0 everywhere and also adapt the datapoints accordingly. Furthermore we should align the structure to have a main and vapp file as in the seat-adjuster example. If we don't do it correct IMO this PR is not helping a lot, since we still need additional work...

How is it as of today? Is Databroker always started with default VSS catalog when starting runtime, i.e. not considering what is written in appManifest? If so it makes sense to adapt examples so they all use default VSS version. I did this work mostly to validate that there are no regressions coming from #139 which does not seem to be the case, if we are to verify/update all aspects of each example more time would be needed.

It also appears to me that many examples are quite similar, so do we need them all? If we would pend more time on them it would also be great if they could be tested as part of CI when updating SDK. That does not happen today, right?

According to databroker: velocitas init should download the specified file and add the config for the databroker. so databroker should always be started with the vss file which is defined in the app manifest.

Agreed that reworking the examples can take a lot of time, that's why it did not happen so far :D

Is there maybe an easy solution to at least be able to use the examples in the template without errors? your initial message at least mentions some more errors besides the ones fixed?

[erikbosch]

Putting this one on hold for now - before merging we should better run through the examples thoroughly and update documentation. Possibly adapt examples so they can be imported by the template.