Update python-package.yml

add requirements.txt file

update flake8 config

fix action config

Fix some small optical changes

Complete client alarms and conditions example for usage with OPCFoundation UA-.NETStandard-Samples Quickstart AlarmConditionServer

Event types can not only contain properties, but also variables. For example the ConditionType, which is the foundation of Alarms and Conditions, contains variables. Add the variables to the generated event filter and event object.

* User-defined PermissionRuleset is now propagated to all InternalServers Endpoinds (also with the one with SecurityPolicy#None)

* Fixed check_user_token method of InternalServer and activate_session of InternalSession to provide an encrypted password to the user-defined UserManager

* Fixed bug in InternalServer when password is not provided
Co-authored-by: Marco Panato <marco.panato_01@univr.it>

* Add check if BrowseName already exists in ParentNode

* Replace try-except blocks
Log error in check_method, not everywhere else

* Remove checks, because they are not cought if UaClient sends addNode request

* Add test to try identifing if BrowseName of new Node is child of ParentNode. If yes, raise error.If Node is root, ignore test.

* Fix tests, because multiple identical BrowseNames with the same parent Node is not allowed.

* Remove exception and ignore root Node directly

* Fix test by change Browsename

* Tidy up codeformat

* Try to get all sorts of NodeId child classes
Delete root Node parent check

* Remove empty aspace arg
Check if Reference is a HasChild Reference or a subtype of it

* Change pytest fixtures to function to not interfere with other tests
Add check if Nodes are in the same Namespace as well
Add duplicated browsename test

* Seperate between root Node or others
As well pushing test again...

* Add more Meta information about Node positions

* Add more Meta information about Nodes which seems to fail

* Change Browsename since both Nodes contain the same Browsename

* Replace dirty print with log

* Register Namespace and import Nodes, because Tests have been interfered eachother

* Try if test interferes with others

* Add check to catch faulty preperation

* Revert "Try if test interferes with others"

This reverts commit b0ac20dc2e898a70a7dedb433da9b88dfb2dc3fd.
Revert "Add check to catch faulty preperation"

This reverts commit c0e5ff6c628076b99d972778fef2dd33132a29a2.

* Change parallel jobs to stages, to reduce the load from Travis

* Check if just this test causes problems

* Fix typo in decorator of pytest

* Change object name
Delete some nodes after test, to be reusable in other
Undo scope back to module

* Add more Node cleanups

* Add cleanup if xml was imported

* Add more Node cleanups to avoid duplicated browsenames while import xml in tests

* Fix list issue in test

* Add even more necessary node cleanups

* Add more Node cleanups

* Remove faulty await

* Add Node cleanup for imported xml Nodes

* Try to get rid of imported nodes from xml

* Getting rid of imported nodes from xml

* Revert Travis
Some PEP8 cleanups

* Fix some changes back to master branch state

* Revert pytest changes

* Avoid multiple Nodes with same Browsename in test server

* Add some more Node cleanups

* Revert wrong changes

* Switch try/except with if ... not/else statement

* Remove empty parent check
Replace explicit in _nodes[] check with a general in _aspace[] check

* Replace lxml with xml.etree.ElementTree
Replace iter() with iterfind()
Remove lxml from setup.py
Remove done FIXME Graffitti
Remove lxml from travis

* Replace wildcard iter via iter over every element to be python3.7 compatible

* added instantiate_optional

* Update uatypes.py

* Revert "Update uatypes.py"

This reverts commit 8e9f907a.

* Update uatypes.py

* Revert "Update uatypes.py"

This reverts commit f073371a.

* Update uatypes.py

* Explicitly cancel automatic discovery renewal

* Update handle when rescheduling the callback

* Don't store the handle for the one-shot renewal callback
Co-authored-by: Kevin Perry <perry@coffee-break.at>

* Added implementation for ModifySubscriptionRequest_Encoding_DefaultBinary, which is sent by some clients (Softing?) after a session has already been created and will kill the session if it's not implemented.

* Minor reshuffling of new code insertions. Added missing import.
Co-authored-by: Jonathan Cutting <jonathan.cutting@sartorius.com>

- Add the possibility to specify a monitoring mode on subscription creation
- Add client and subscription methods to change the publishing and monitoring mode of an existing subscription
- Add a timeout on connect to force the connection to fail if the server can't process it.
- Add a shortcut for the service_level

If we don't, this can prevent reconnection since the task is still running, and the previous task instance could be hanging on a previous request that has never completed (i.e network issue).

Yes, there's no timeout on request coming from the publish_loop, so we
must ensure the publish_task is always cancelled. Hence, the
uaclient.close_session is always called on disconnect.

Upgrade test cases from ubuntu xenial to bionic
Update README

Mentioned in #314

String are immutable, therefore the password is never encoded and it
throws this error when it's a string:

```
...../cryptography/hazmat/backends/openssl/backend.py in _load_key(self, openssl_read_func, convert_func, data, password)
   1284         userdata = self._ffi.new("CRYPTOGRAPHY_PASSWORD_DATA *")
   1285         if password is not None:
-> 1286             utils._check_byteslike("password", password)
   1287             password_ptr = self._ffi.from_buffer(password)
   1288             userdata.password = password_ptr

...../cryptography/utils.py in _check_byteslike(name, value)
     36         memoryview(value)
     37     except TypeError:
---> 38         raise TypeError("{} must be bytes-like".format(name))
     39
     40

TypeError: password must be bytes-like
```

This patch fixes this as well as some typing inaccuracy introduced by #281