Compiling with conformance, feature and deviation

YANG
1

When compiling fxs files with command confdc, I have a question on how the option " -C conformance, --conformance conformance" impacts the output fxs file. Here are 2 commands to compile fxs file and the only difference between them is the conformance option. One is compiled for implemented(default). The other is for imported. Is there any difference between the two generated fxs files?
1) /opt/confd/bin/confdc --yangpath /opt/adp/yang -c /tmp/yangArchive028486359/ietf-interfaces@2018-02-20.yang --use-description -o /tmp/yangArchive028486359/ietf-interfaces.fxs --yangpath /tmp/yangArchive028486359 --deviation /tmp/yangArchive028486359/com-interfaces-dev-pc5gc.yang --deviation /tmp/yangArchive028486359/com-interfaces-ext-pc5gc.yang --deviation /tmp/yangArchive028486359/com-ip-ext-pc5gc.yang --deviation /tmp/yangArchive028486359/com-pc-up-data-plane-interface-3gpp.yang --deviation /tmp/yangArchive028486359/com-pc-up-pfcp-endpoint-interface-3gpp.yang --deviation /tmp/yangArchive028486359/ietf-interfaces-common.yang --deviation /tmp/yangArchive028486359/ietf-ip@2018-02-22.yang --deviation /tmp/yangArchive028486359/ietf-network-instance@2019-01-21.yang -F ietf-interfaces:
2) /opt/confd/bin/confdc --yangpath /opt/adp/yang -c /tmp/yangArchive028486359/ietf-interfaces@2018-02-20.yang --use-description -o /tmp/yangArchive028486359/ietf-interfaces.fxs --yangpath /tmp/yangArchive028486359 --deviation /tmp/yangArchive028486359/com-interfaces-dev-pc5gc.yang --deviation /tmp/yangArchive028486359/com-interfaces-ext-pc5gc.yang --deviation /tmp/yangArchive028486359/com-ip-ext-pc5gc.yang --deviation /tmp/yangArchive028486359/com-pc-up-data-plane-interface-3gpp.yang --deviation /tmp/yangArchive028486359/com-pc-up-pfcp-endpoint-interface-3gpp.yang --deviation /tmp/yangArchive028486359/ietf-interfaces-common.yang --deviation /tmp/yangArchive028486359/ietf-ip@2018-02-22.yang --deviation /tmp/yangArchive028486359/ietf-network-instance@2019-01-21.yang -F ietf-interfaces: -C ietf-interfaces:import
Per our internal document, “-F ietf-interfaces:” means no features are wanted for a particular module. If no features are listed for a module, then all features are implicitly selected. So any difference between command 2) and 3) if there are features in ietf-interfaces module? And what the impact of deviation?
3) /opt/confd/bin/confdc --yangpath /opt/adp/yang -c /tmp/yangArchive028486359/ietf-interfaces@2018-02-20.yang --use-description -o /tmp/yangArchive028486359/ietf-interfaces.fxs --yangpath /tmp/yangArchive028486359 --deviation /tmp/yangArchive028486359/com-interfaces-dev-pc5gc.yang --deviation /tmp/yangArchive028486359/com-interfaces-ext-pc5gc.yang --deviation /tmp/yangArchive028486359/com-ip-ext-pc5gc.yang --deviation /tmp/yangArchive028486359/com-pc-up-data-plane-interface-3gpp.yang --deviation /tmp/yangArchive028486359/com-pc-up-pfcp-endpoint-interface-3gpp.yang --deviation /tmp/yangArchive028486359/ietf-interfaces-common.yang --deviation /tmp/yangArchive028486359/ietf-ip@2018-02-22.yang --deviation /tmp/yangArchive028486359/ietf-network-instance@2019-01-21.yang -C ietf-interfaces:import

Thank you very much.

2

Compiling a YANG module with -C import means that you are not interested in the configuration data tree modeled by the module, that you need the module only for its typedefs or groupings or possibly RPCs or status data; I believe that for all practical purposes -C import is equivalent to commenting out or removing the configuration data model from the module.

For ietf-interfaces, I would expect you want to configure interfaces, so you need the tree and hence you need -C implement.

3

Thanks for your reply, mvf.
For RPCs or status data, I still not sure if it will be included in the fxs file when compiled with “-C import”,
Per https://tools.ietf.org/html/rfc7950#section-5.6.5:

A server implements a module if it implements the module’s data
nodes, RPCs, actions, notifications, and deviations.

RPCs should be included when compiled with “-C implement” and not be included when compiled with “-C import”?

And according to the definition of data tree in RFC 7950:

data tree: An instantiated tree of any data modeled with YANG,
e.g., configuration data, state data, combined configuration and
state data, RPC or action input, RPC or action output, or
notification.

State data should also not be included when compiled with “-C import”?
BRs
Michael

4

Yes, I believe you are right: a server does not (have to) implement “protocol-accessible” objects of a import-only module, and RPCs or state data quite certainly are such objects. I guess it is more an information to the client - it should not try to access such objects; and I’m sure it means that when you are implementing RPCs or data-provider callbacks for objects from a module, you should compile it with -C implement.