vss-tools versioning

[ppb2020]

I was playing with release/2.2, as this is the version we started with originally. When I tried to run one of the conversion tools (vspec2json.py), it complained that no quantities and no units were specified. This, even though the help information clearly shows these (options -q and -u) as optional. I then obtained the relevant files from master only to run into another issue, that some attributes (enum especially) were not recognized (not a core or known attribute).

It seems that vss-tools in release/2.2 is running a version that is not compatible. When I looked at the vss-tools repository, I noticed that there is no release/2.2 version. Am I missing something or is this an issue?

[erikbosch]

In the past there were no formal releases/tags of vss-tools, they were only indirectly released as being part of the VSS-release. Since some time we also tag vss-tools, and so far they generally have the same version number as the VSS version released at the same time, but that will not necessarily be true going forward.

When I run the vss-tools versions included by submodule in vss 2.2 I do not get any error/warning (see below).

In VSS 3.0 we introduced a change to VSS syntax, enum was renamed to allowed, see https://github.com/COVESA/vehicle_signal_specification/blob/master/CHANGELOG.md#enumallowed-attribute. We did not keep any backward support in vss-tools, so a VSS catalog using VSS 2.X syntax can not be used as input to later versions of VSS-tools.

Concerning units/quantities - that was quite recently changed in VSS/VSS-tools. In the past the (default) unit-file was included as part of vss-tools, but it has recently been moved to be hosted by the catalog instead. In recent vss-tools, the -u is optional, but at the same time there must be some units and if -u is not defined recent vss-tools will look at the same location as the root *.vspec file for units. Some info can be found in https://github.com/COVESA/vss-tools/blob/master/CHANGELOG.md. If you use a newer vss-tools together with an older VSS catalog you will likely get an error as the vss-tools cannot find the default units. A possible solution is to first check out the vss-tools submodule version linked from the older vss version and copy it to the folder of the root *.vspec. For "missing quantities" you shold at most get an info-message, I think

In general - as of today we only test as part of release latest vss-tools vs latest vss (catalog), we do not test any other combination and in general we do not put any efforts in making sure vss-tools support older versions. If we want to make vss-tools more independent we could discuss if we want to support multiple VSS-versions in parallel, for example requiring that VSS-tools 5.0 supports all VSS versions 4-1-5.0

Example with VSS 2.2

erik@debian4:~/vehicle_signal_specification$ git checkout release/2.2
M	vss-tools
Switched to branch 'release/2.2'
Your branch is up to date with 'upstream/release/2.2'.
erik@debian4:~/vehicle_signal_specification$ git submodule update --init
Submodule path 'vss-tools': checked out 'd5a2e70f58b99c7ce19167309a210922c42e8cfc'
erik@debian4:~/vehicle_signal_specification$ make json
./vss-tools/vspec2json.py -I ./spec ./spec/VehicleSignalSpecification.vspec vss_rel_$(cat VERSION).json
Loading vspec...
Recursing tree and creating JSON...
All done.

[erikbosch]

This is related to #734