[ODLPARENT-235] Add parent for static features

Issue split — Tue, 12 Jul 2022 12:43:45 +0000

Completely generated features have a number of downsides:

they require a template to use version ranges, for example for MRI projects
they end up over-including things, hence they typically never catch anything at compile-time
more advanced features of feature.xml are simply not available, as they are not expressible in pom.xml

At the end of the day, we are getting to a point where most features have a template anyway. Rather than battling this reality, we should embrace it and take one step back – i.e. use a feature.xml template with version expansion based on pom.xml and test that. We used to have this in Karaf 3, so this is nothing new.

We need to create a plugin which will perform the appropriate transformation – this can be XSLT or pretty much anything – the template is an XML, where we are going to perform a rather trivial substitution:

we match only <bundle/> tags which contain a maven coordinate (starting with mvn: or wrap:mvn: )
we match only <feature/> tags with version specification and test content
within that coordinate we look for mustache-enclosed tag
we replace the entire contents of mustache

There are only two substitutions we can make, both working on project dependency resolution. Assuming target artifact is resolved to "1.2.3", those are:

<bundle>mvn:org.opendaylight.genius/lockmanager-api/{{versionAsInProject}}</bundle>
<feature version="{{semVerRange}}">odl-apache-commons-net</feature>

This would result in:

<bundle>mvn:org.opendaylight.genius/lockmanager-api/1.2.3</bundle>
<feature version="[1.2.3,2)">odl-apache-commons-net</feature>

OpenDaylight JIRA

[ODLPARENT-235] Add parent for static features