Add netconf_get module (#39869)

* Add netconf_get module

Implements part-1 of proposal #104
https://github.com/ansible/proposals/issues/104

*  Add netconf_get module
*  Refactor `get`, `get_config`, `lock`, `unlock`
   and `discard_changes` netconf plugin api's
*  Add netconf module_utils file which netconf module
   related common functions
*  Refactor junos and iosxr netconf plugins

* Fix source option handling

* Fix review comments

* Update botmeta file

* Update review comments and add support for lock

* Lock update fix

* Fix CI issue

* Add integration test and minor fixes

* Fix review comments

* Fix CI failure

* Fix CI issues

* Fix CI issues

* Fix review comments and update integration test

* Fix review comments

* Fix review comments

* Fix review comments

Fix reveiw comments

lib/ansible/plugins/netconf/__init__.py

@@ -110,22 +110,35 @@ class NetconfBase(with_metaclass(ABCMeta, object)):
             raise Exception(to_xml(msg))
 
     @ensure_connected
-    def get_config(self, *args, **kwargs):
-        """Retrieve all or part of a specified configuration.
-           :source: name of the configuration datastore being queried
-           :filter: specifies the portion of the configuration to retrieve
-           (by default entire configuration is retrieved)"""
-        resp = self.m.get_config(*args, **kwargs)
+    def get_config(self, source=None, filter=None):
+        """Retrieve all or part of a specified configuration
+           (by default entire configuration is retrieved).
+
+        :param source: Name of the configuration datastore being queried, defaults to running datastore
+        :param filter: This argument specifies the portion of the configuration data to retrieve
+        :return: Returns xml string containing the RPC response received from remote host
+        """
+        if isinstance(filter, list):
+            filter = tuple(filter)
+
+        if not source:
+            source = 'running'
+        resp = self.m.get_config(source=source, filter=filter)
         return resp.data_xml if hasattr(resp, 'data_xml') else resp.xml
 
     @ensure_connected
-    def get(self, *args, **kwargs):
-        """Retrieve running configuration and device state information.
-        *filter* specifies the portion of the configuration to retrieve
-        (by default entire configuration is retrieved)
+    def get(self, filter=None):
+        """Retrieve device configuration and state information.
+
+        :param filter: This argument specifies the portion of the state data to retrieve
+                        (by default entire state data is retrieved)
+        :return: Returns xml string containing the RPC response received from remote host
         """
-        resp = self.m.get(*args, **kwargs)
-        return resp.data_xml if hasattr(resp, 'data_xml') else resp.xml
+        if isinstance(filter, list):
+            filter = tuple(filter)
+        resp = self.m.get(filter=filter)
+        response = resp.data_xml if hasattr(resp, 'data_xml') else resp.xml
+        return response
 
     @ensure_connected
     def edit_config(self, *args, **kwargs):
@@ -162,26 +175,42 @@ class NetconfBase(with_metaclass(ABCMeta, object)):
         return resp.data_xml if hasattr(resp, 'data_xml') else resp.xml
 
     @ensure_connected
-    def lock(self, *args, **kwargs):
-        """Allows the client to lock the configuration system of a device.
-        *target* is the name of the configuration datastore to lock
+    def lock(self, target=None):
         """
-        resp = self.m.lock(*args, **kwargs)
+        Allows the client to lock the configuration system of a device.
+        :param target: is the name of the configuration datastore to lock,
+                        defaults to candidate datastore
+        :return: Returns xml string containing the RPC response received from remote host
+        """
+        if not target:
+            target = 'candidate'
+        resp = self.m.lock(target=target)
         return resp.data_xml if hasattr(resp, 'data_xml') else resp.xml
 
     @ensure_connected
-    def unlock(self, *args, **kwargs):
+    def unlock(self, target=None):
+        """
+        Release a configuration lock, previously obtained with the lock operation.
+        :param target: is the name of the configuration datastore to unlock,
+                       defaults to candidate datastore
+        :return: Returns xml string containing the RPC response received from remote host
+        """
         """Release a configuration lock, previously obtained with the lock operation.
         :target: is the name of the configuration datastore to unlock
         """
-        resp = self.m.unlock(*args, **kwargs)
+        if not target:
+            target = 'candidate'
+        resp = self.m.unlock(target=target)
         return resp.data_xml if hasattr(resp, 'data_xml') else resp.xml
 
     @ensure_connected
-    def discard_changes(self, *args, **kwargs):
-        """Revert the candidate configuration to the currently running configuration.
-        Any uncommitted changes are discarded."""
-        resp = self.m.discard_changes(*args, **kwargs)
+    def discard_changes(self):
+        """
+        Revert the candidate configuration to the currently running configuration.
+        Any uncommitted changes are discarded.
+        :return: Returns xml string containing the RPC response received from remote host
+        """
+        resp = self.m.discard_changes()
         return resp.data_xml if hasattr(resp, 'data_xml') else resp.xml
 
     @ensure_connected
@@ -245,4 +274,28 @@ class NetconfBase(with_metaclass(ABCMeta, object)):
         """Fetch file over scp from remote device"""
         pass
 
+    def get_device_operations(self, server_capabilities):
+        operations = {}
+        capabilities = '\n'.join(server_capabilities)
+        operations['supports_commit'] = True if ':candidate' in capabilities else False
+        operations['supports_defaults'] = True if ':with-defaults' in capabilities else False
+        operations['supports_confirm_commit'] = True if ':confirmed-commit' in capabilities else False
+        operations['supports_startup'] = True if ':startup' in capabilities else False
+        operations['supports_xpath'] = True if ':xpath' in capabilities else False
+        operations['supports_writeable_running'] = True if ':writable-running' in capabilities else False
+
+        operations['lock_datastore'] = []
+        if operations['supports_writeable_running']:
+            operations['lock_datastore'].append('running')
+
+        if operations['supports_commit']:
+            operations['lock_datastore'].append('candidate')
+
+        if operations['supports_startup']:
+            operations['lock_datastore'].append('startup')
+
+        operations['supports_lock'] = True if len(operations['lock_datastore']) else False
+
+        return operations
+
 # TODO Restore .xml, when ncclient supports it for all platforms