Proposal of API for discussion

[dbarrosop]

Mostly copy/pasting from napalm-base with tiny minor adjustments. Feel free to discuss in the code which parts we should change.

Also, I was thinking that instead of overriding methods, more specific drivers could implement an interface. For example:

class BaseNetworkDriver(object):
    ...
    def open(self):
        try:
            self._open()
        except Exception as e:
            raise Blah(orig_exc=e)

    def _open(self):
        raise NotImplementedError


class IOSDriver(BaseNetworkDriver):

    def _open(self):
        # code goes here

Or even decoupling napalm from the driver interface. For example:

class Napalm(object):
    """ This is the class users interact with."""

    def __init__(self, hostname, username, password, os_name, **kwargs):
        driver = get_network_driver(os_name)
        self.device = driver(hostname, username, password, **kwargs)
        ...

    def cli(self, commands):
        try:
            self.device.cli(commands)
        except Exception as e:
            raise UncaughtException(orig_exc=e)


class DriverInterface(object):
    """ This class simply defines/documents the interface. """

    def cli(self, commands):
        raise NotImplementedError


class IOSDriver(DriverInterface):
   """ This is a driver. """

    def cli(self, commands):
        # code goes here

Both approaches will give us more control and allow us to write wrappers to verify exceptions and put common code.

[mirceaulinic]

Totally agree on this.
I see an exceptions module below. Wouldn't we use the napalm-base exceptions?
We have this epic: napalm-automation/napalm-base#218 which is supposed to track some more exceptions to be introduced.

[mirceaulinic]

Oh, I see. This would basically replace the napalm-base itself...