[proposal] NetlinkSocketBase methods to return iterators instead of lists

[svinota]

Current situation

Methods:

• get()
• nlm_request()
• nlm_request_batch()

The methods return messages lists by default, and iterators if the nlm_generator constructor parameter is True
or pyroute2.config.nlm_generator == True.

The plan

Return iterators unconditionally as the only option and make API consistent.

The reason

The support of both iterators and lists:

• requires monkey patching
• complicates testing
• complicates code understanding

To try already now

It is possible to try the new API now. Thus the methods that return lists should return iterators. Some issues are still possible, though. To be fixed asap.

option 1. using the config

from pyroute2 import config, IPRoute

config.nlm_generator = True

ipr = IPRoute()

option 2. using the constructor parameter

from pyroute2 import IPRoute

ipr = IPRoute(nlm_generator=True)