Replace os path with pathlib (#1179)

* replaced os.path with pathlib.Path

* fixed some type hinting; added FIXME for critical vulnerability

* added string and path support for certificate paths because path only broke the API. BUT we should stop using strings for paths in the future..

---------

Co-authored-by: ratara <noreply>

.gitignore

@@ -22,6 +22,6 @@ examples/history.db
 /.settings/
 /venv/
 .eggs*
+.vscode
 .coverage
 schemas/UA-Nodese*
-.vscode

asyncua/client/client.py

@@ -2,6 +2,7 @@ import asyncio
 import logging
 from typing import List, Union, Coroutine, Optional, Type
 from urllib.parse import urlparse, unquote
+from pathlib import Path
 
 from asyncua import ua
 from .ua_client import UaClient
@@ -218,7 +219,7 @@ class Client:
         """
         self.user_certificate = await uacrypto.load_certificate(path, extension)
 
-    async def load_private_key(self, path: str, password: Optional[Union[str, bytes]] = None, extension: Optional[str] = None):
+    async def load_private_key(self, path: Path, password: Optional[Union[str, bytes]] = None, extension: Optional[str] = None):
         """
         Load user private key. This is used for authenticating using certificate
         """

asyncua/crypto/uacrypto.py

-import os
+from pathlib import Path
 import aiofiles
 from typing import Optional, Union
 
@@ -17,12 +17,12 @@ from dataclasses import dataclass
 
 @dataclass
 class CertProperties:
-    path_or_content: Union[str, bytes]
+    path_or_content: Union[bytes, Path, str]
     extension: Optional[str] = None
     password: Optional[Union[str, bytes]] = None
 
 
-async def get_content(path_or_content: Union[str, bytes]) -> bytes:
+async def get_content(path_or_content: Union[str, bytes, Path]) -> bytes:
     if isinstance(path_or_content, bytes):
         return path_or_content
 
@@ -30,8 +30,13 @@ async def get_content(path_or_content: Union[str, bytes]) -> bytes:
         return await f.read()
 
 
-async def load_certificate(path_or_content: Union[str, bytes], extension: Optional[str] = None):
-    _, ext = os.path.splitext(path_or_content)
+async def load_certificate(path_or_content: Union[bytes, str, Path], extension: Optional[str] = None):
+    if isinstance(path_or_content, str):
+        ext = Path(path_or_content).suffix
+    elif isinstance(path_or_content, Path):
+        ext = path_or_content.suffix
+    else:
+        ext = ''
 
     content = await get_content(path_or_content)
     if ext == ".pem" or extension == 'pem' or extension == 'PEM':
@@ -46,10 +51,15 @@ def x509_from_der(data):
     return x509.load_der_x509_certificate(data, default_backend())
 
 
-async def load_private_key(path_or_content: Union[str, bytes],
+async def load_private_key(path_or_content: Union[str, Path, bytes],
                            password: Optional[Union[str, bytes]] = None,
                            extension: Optional[str] = None):
-    _, ext = os.path.splitext(path_or_content)
+    if isinstance(path_or_content, str):
+        ext = Path(path_or_content).suffix
+    elif isinstance(path_or_content, Path):
+        ext = path_or_content.suffix
+    else:
+        ext = ''
     if isinstance(password, str):
         password = password.encode('utf-8')
 
@@ -149,6 +159,7 @@ def decrypt_rsa15(private_key, data):
 
 
 def cipher_aes_cbc(key, init_vec):
+    # FIXME sonarlint reports critical vulnerability (python:S5542) 
     return Cipher(algorithms.AES(key), modes.CBC(init_vec), default_backend())
 
 

asyncua/server/internal_server.py

@@ -7,7 +7,7 @@ import asyncio
 from datetime import datetime, timedelta
 from copy import copy
 from struct import unpack_from
-import os
+from pathlib import Path
 import logging
 from urllib.parse import urlparse
 from typing import Coroutine, Tuple
@@ -120,8 +120,8 @@ class InternalServer:
     async def load_standard_address_space(self, shelf_file=None):
         if shelf_file:
             is_file = await asyncio.get_running_loop().run_in_executor(
-                None, os.path.isfile, shelf_file
-            ) or await asyncio.get_running_loop().run_in_executor(None, os.path.isfile, f'{shelf_file}.db')
+                None, Path.is_file, shelf_file
+            ) or await asyncio.get_running_loop().run_in_executor(None, Path.is_file, f'{shelf_file}.db')
             if is_file:
                 # import address space from shelf
                 await asyncio.get_running_loop().run_in_executor(None, self.aspace.load_aspace_shelf, shelf_file)

asyncua/server/server.py

@@ -8,6 +8,7 @@ import math
 from datetime import timedelta, datetime
 from urllib.parse import urlparse
 from typing import Coroutine, Optional, Tuple, Union
+from pathlib import Path
 
 from asyncua import ua
 from .binary_server_asyncio import BinaryServer
@@ -227,7 +228,7 @@ class Server:
         """
         self.certificate = await uacrypto.load_certificate(path_or_content, format)
 
-    async def load_private_key(self, path_or_content: Union[str, bytes], password=None, format=None):
+    async def load_private_key(self, path_or_content: Union[str, Path, bytes], password=None, format=None):
         self.iserver.private_key = await uacrypto.load_private_key(path_or_content, password, format)
 
     def disable_clock(self, val: bool = True):

asyncua/server/user_managers.py

-from asyncua.crypto import uacrypto
 import logging
-from asyncua.server.users import UserRole, User
+from pathlib import Path
+from typing import Union
+
+from asyncua.crypto import uacrypto
+from asyncua.server.users import User, UserRole
 
 
 class UserManager:
@@ -26,7 +29,7 @@ class CertificateUserManager:
     def __init__(self):
         self._trusted_certificates = {}
 
-    async def add_role(self, certificate_path: str, user_role: UserRole, name: str, format: str = None):
+    async def add_role(self, certificate_path: Path, user_role: UserRole, name: str, format: Union[str, None] = None):
         certificate = await uacrypto.load_certificate(certificate_path, format)
         if name is None:
             raise KeyError
@@ -48,8 +51,8 @@ class CertificateUserManager:
         else:
             return correct_users[0]
 
-    async def add_user(self, certificate_path: str, name: str, format: str = None):
+    async def add_user(self, certificate_path: Path, name: str, format: Union[str, None] = None):
         await self.add_role(certificate_path=certificate_path, user_role=UserRole.User, name=name, format=format)
 
-    async def add_admin(self, certificate_path: str, name:str, format: str = None):
+    async def add_admin(self, certificate_path: Path, name:str, format: Union[str, None] = None):
         await self.add_role(certificate_path=certificate_path, user_role=UserRole.Admin, name=name, format=format)

asyncua/sync.py

@@ -2,6 +2,7 @@
 sync API of asyncua
 """
 import asyncio
+from pathlib import Path
 from threading import Thread, Condition
 import logging
 from typing import List, Tuple, Union, Optional
@@ -647,7 +648,7 @@ class XmlExporter:
         pass
 
     @syncmethod
-    def write_xml(self, xmlpath, pretty=True):
+    def write_xml(self, xmlpath: Path, pretty=True):
         pass
 
 

docs/conf.py

-# Configuration file for the Sphinx documentation builder.
-#
-# For the full list of built-in configuration values, see the documentation:
-# https://www.sphinx-doc.org/en/master/usage/configuration.html
-
-# -- Project information -----------------------------------------------------
-# https://www.sphinx-doc.org/en/master/usage/configuration.html#project-information
-from importlib import metadata
-
-project = "opcua-asyncio"
-copyright = "2022, opcua-asyncio contributors"
-author = "opcua-asyncio contributors"
-# release = "0.95.0"
-version = metadata.version('asyncua')
-
-# -- General configuration ---------------------------------------------------
-# https://www.sphinx-doc.org/en/master/usage/configuration.html#general-configuration
-
-extensions = [
-    "sphinx.ext.autodoc",
-    "sphinx.ext.autosectionlabel",
-    "sphinx.ext.intersphinx",
-    "sphinx.ext.todo",
-    # "sphinx_copybutton",  # Currently not working with line numbers
-]
-
-templates_path = ["_templates"]
-exclude_patterns = ["_build", "Thumbs.db", ".DS_Store"]
-
-
-# -- Options for HTML output -------------------------------------------------
-# https://www.sphinx-doc.org/en/master/usage/configuration.html#options-for-html-output
-# https://pydata-sphinx-theme.readthedocs.io/en/latest/user_guide/index.html
-html_theme = "pydata_sphinx_theme"
-html_static_path = ["_static"]
-
-html_theme_options = {
-    "github_url": "https://github.com/FreeOpcUa/opcua-asyncio",
-    "show_toc_level": 2, # Visible levels in the right navigation
-    "show_nav_level": 2, # Default levels of expanded elements in the left navigation
-}
-
-
-# -- Options for sphinx.ext.autosectionlabel ---------------------------------
-# https://www.sphinx-doc.org/en/master/usage/extensions/autosectionlabel.html
-autosectionlabel_prefix_document = True
-
-# -- Options for sphinx.ext.intersphinx --------------------------------------
-# https://www.sphinx-doc.org/en/master/usage/extensions/intersphinx.html
-intersphinx_mapping = {'python': ('https://docs.python.org/3', None)}
-
-# -- Options for sphinx.ext.todo ---------------------------------------------
-# https://www.sphinx-doc.org/en/master/usage/extensions/todo.html
-todo_include_todos = True
+# Configuration file for the Sphinx documentation builder.
+#
+# For the full list of built-in configuration values, see the documentation:
+# https://www.sphinx-doc.org/en/master/usage/configuration.html
+
+# -- Project information -----------------------------------------------------
+# https://www.sphinx-doc.org/en/master/usage/configuration.html#project-information
+from importlib import metadata
+
+project = "opcua-asyncio"
+copyright = "2022, opcua-asyncio contributors"
+author = "opcua-asyncio contributors"
+# release = "0.95.0"
+version = metadata.version('asyncua')
+
+# -- General configuration ---------------------------------------------------
+# https://www.sphinx-doc.org/en/master/usage/configuration.html#general-configuration
+
+extensions = [
+    "sphinx.ext.autodoc",
+    "sphinx.ext.autosectionlabel",
+    "sphinx.ext.intersphinx",
+    "sphinx.ext.todo",
+    # "sphinx_copybutton",  # Currently not working with line numbers
+]
+
+templates_path = ["_templates"]
+exclude_patterns = ["_build", "Thumbs.db", ".DS_Store"]
+
+
+# -- Options for HTML output -------------------------------------------------
+# https://www.sphinx-doc.org/en/master/usage/configuration.html#options-for-html-output
+# https://pydata-sphinx-theme.readthedocs.io/en/latest/user_guide/index.html
+html_theme = "pydata_sphinx_theme"
+html_static_path = ["_static"]
+
+html_theme_options = {
+    "github_url": "https://github.com/FreeOpcUa/opcua-asyncio",
+    "show_toc_level": 2, # Visible levels in the right navigation
+    "show_nav_level": 2, # Default levels of expanded elements in the left navigation
+}
+
+
+# -- Options for sphinx.ext.autosectionlabel ---------------------------------
+# https://www.sphinx-doc.org/en/master/usage/extensions/autosectionlabel.html
+autosectionlabel_prefix_document = True
+
+# -- Options for sphinx.ext.intersphinx --------------------------------------
+# https://www.sphinx-doc.org/en/master/usage/extensions/intersphinx.html
+intersphinx_mapping = {'python': ('https://docs.python.org/3', None)}
+
+# -- Options for sphinx.ext.todo ---------------------------------------------
+# https://www.sphinx-doc.org/en/master/usage/extensions/todo.html
+todo_include_todos = True

examples/simple-client-server-xml/server.py

-import os.path
 import asyncio
 import logging
+from pathlib import Path
 
-from asyncua import ua, uamethod, Server
+from asyncua import Server, ua, uamethod
 
 
 @uamethod
@@ -85,11 +85,11 @@ class HelloServer:
 
 
 async def main():
-    script_dir = os.path.dirname(__file__)
+    script_dir = Path(__file__).parent
     async with HelloServer(
         "opc.tcp://0.0.0.0:4840/freeopcua/server/",
         "FreeOpcUa Example Server",
-        os.path.join(script_dir, "test_saying.xml"),
+        script_dir / "test_saying.xml",
     ) as server:
         while True:
             await asyncio.sleep(1)

schemas/generate_protocol_python.py

-import os
+from pathlib import Path
 import datetime
 
-BASE_DIR = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
+BASE_DIR = Path(__file__).absolute().parent.parent
 
 IgnoredEnums = ["NodeIdType"]
 IgnoredStructs = ["QualifiedName", "NodeId", "ExpandedNodeId", "Variant", "DataValue",
@@ -217,8 +217,8 @@ class CodeGenerator:
 if __name__ == '__main__':
     import generate_model_from_nodeset as gm
 
-    xml_path = os.path.join(BASE_DIR, 'schemas', 'UA-Nodeset-master', 'Schema', 'Opc.Ua.NodeSet2.Services.xml')
-    protocol_path = os.path.join(BASE_DIR, "asyncua", "ua", "uaprotocol_auto.py")
+    xml_path = BASE_DIR.joinpath('schemas', 'UA-Nodeset-master', 'Schema', 'Opc.Ua.NodeSet2.Services.xml') 
+    protocol_path = BASE_DIR.joinpath("asyncua", "ua", "uaprotocol_auto.py")
     p = gm.Parser(xml_path)
     model = p.parse()
     gm.nodeid_to_names(model)

tests/conftest.py

 import asyncio
 import pytest
 import operator
-import os
+from pathlib import Path
 import socket
 from concurrent.futures import ThreadPoolExecutor
 from multiprocessing import Process, Condition, Event
@@ -268,19 +268,19 @@ async def history_server(request):
 
 @pytest.fixture(scope="session")
 def client_key_and_cert(request):
-    base_dir = os.path.dirname(os.path.dirname(__file__))
-    cert_dir = os.path.join(base_dir, "examples/certificates") + os.sep
-    key = f"{cert_dir}peer-private-key-example-1.pem"
-    cert = f"{cert_dir}peer-certificate-example-1.der"
+    base_dir = Path(__file__).parent.parent
+    cert_dir = base_dir / "examples/certificates"
+    key = cert_dir / "peer-private-key-example-1.pem"
+    cert = cert_dir / "peer-certificate-example-1.der"
     return key, cert
 
 
 @pytest.fixture(scope="session")
 def server_key_and_cert(request):
-    base_dir = os.path.dirname(os.path.dirname(__file__))
-    cert_dir = os.path.join(base_dir, "examples") + os.sep
-    key = f"{cert_dir}private-key-example.pem"
-    cert = f"{cert_dir}certificate-example.der"
+    base_dir = Path(__file__).parent.parent
+    cert_dir = base_dir / "examples"
+    key = cert_dir / "private-key-example.pem"
+    cert = cert_dir / "certificate-example.der"
     return key, cert
 
 

tests/test_common.py

@@ -9,9 +9,9 @@ same api on server and client side
 import asyncio
 import contextlib
 import math
-import os
 import tempfile
 from datetime import datetime, timedelta
+from pathlib import Path
 
 import pytest
 
@@ -20,7 +20,7 @@ from asyncua.common import ua_utils
 from asyncua.common.copy_node_util import copy_node
 from asyncua.common.instantiate_util import instantiate
 from asyncua.common.methods import call_method_full
-from asyncua.common.sql_injection import validate_table_name, SqlInjectionError
+from asyncua.common.sql_injection import SqlInjectionError, validate_table_name
 from asyncua.common.structures104 import new_enum, new_struct, new_struct_field
 from asyncua.ua.ua_binary import struct_from_binary, struct_to_binary
 
@@ -1426,9 +1426,9 @@ async def test_nested_struct_arrays(opc):
 @contextlib.contextmanager
 def expect_file_creation(filename: str):
     with tempfile.TemporaryDirectory() as tmpdir:
-        path = os.path.join(tmpdir, filename)
+        path = Path(tmpdir) / filename
         yield path
-        assert os.path.isfile(path), f"File {path} should have been created"
+        assert Path.is_file(path), f"File {path} should have been created"
 
 
 async def test_custom_struct_export(opc):

tests/test_crypto_connect.py

-import os
+from pathlib import Path
 import pytest
 import asyncio
 
@@ -29,26 +29,26 @@ port_num3 = 48516
 uri_crypto = "opc.tcp://127.0.0.1:{0:d}".format(port_num1)
 uri_no_crypto = "opc.tcp://127.0.0.1:{0:d}".format(port_num2)
 uri_crypto_cert = "opc.tcp://127.0.0.1:{0:d}".format(port_num3)
-BASE_DIR = os.path.dirname(os.path.dirname(__file__))
-EXAMPLE_PATH = os.path.join(BASE_DIR, "examples") + os.sep
-srv_crypto_params = [(f"{EXAMPLE_PATH}private-key-example.pem",
-                      f"{EXAMPLE_PATH}certificate-example.der"),
-                     (f"{EXAMPLE_PATH}private-key-3072-example.pem",
-                      f"{EXAMPLE_PATH}certificate-3072-example.der")]
+BASE_DIR = Path(__file__).parent.parent
+EXAMPLE_PATH = BASE_DIR / "examples"
+srv_crypto_params = [(EXAMPLE_PATH / "private-key-example.pem",
+                      EXAMPLE_PATH / "certificate-example.der"),
+                     (EXAMPLE_PATH / "private-key-3072-example.pem",
+                      EXAMPLE_PATH / "certificate-3072-example.der")]
 
 peer_creds = {
-    "certificate": f"{EXAMPLE_PATH}certificates/peer-certificate-example-1.der",
-    "private_key": f"{EXAMPLE_PATH}certificates/peer-private-key-example-1.pem"
+    "certificate": EXAMPLE_PATH / "certificates/peer-certificate-example-1.der",
+    "private_key": EXAMPLE_PATH / "certificates/peer-private-key-example-1.pem"
 }
 
 unauthorized_peer_creds = {
-    "certificate": f"{EXAMPLE_PATH}certificates/peer-certificate-example-2.der",
-    "private_key": f"{EXAMPLE_PATH}certificates/peer-private-key-example-2.pem"
+    "certificate": EXAMPLE_PATH / "certificates/peer-certificate-example-2.der",
+    "private_key": EXAMPLE_PATH / "certificates/peer-private-key-example-2.pem"
 }
 
 encrypted_private_key_peer_creds = {
-    "private_key": f"{EXAMPLE_PATH}certificates/peer-private-key-example-encrypted-private-key.pem",
-    "certificate": f"{EXAMPLE_PATH}certificates/peer-certificate-example-encrypted-private-key.der",
+    "private_key": EXAMPLE_PATH / "certificates/peer-private-key-example-encrypted-private-key.pem",
+    "certificate": EXAMPLE_PATH / "certificates/peer-certificate-example-encrypted-private-key.der",
     "password": b"password"
 }
 
@@ -130,14 +130,14 @@ async def test_nocrypto_fail(srv_no_crypto):
     clt = Client(uri_no_crypto)
     with pytest.raises(ua.UaError):
         await clt.set_security_string(
-            f"Basic256Sha256,Sign,{EXAMPLE_PATH}certificate-example.der,{EXAMPLE_PATH}private-key-example.pem")
+            f"Basic256Sha256,Sign,{EXAMPLE_PATH / 'certificate-example.der'},{EXAMPLE_PATH / 'private-key-example.pem'}")
 
 
 async def test_basic256(srv_crypto_all_certs):
     _, cert = srv_crypto_all_certs
     clt = Client(uri_crypto)
     await clt.set_security_string(
-        f"Basic256Sha256,Sign,{EXAMPLE_PATH}certificate-example.der,{EXAMPLE_PATH}private-key-example.pem,{cert}"
+        f"Basic256Sha256,Sign,{EXAMPLE_PATH / 'certificate-example.der'},{EXAMPLE_PATH / 'private-key-example.pem'},{cert}"
     )
     async with clt:
         assert await clt.nodes.objects.get_children()
@@ -147,7 +147,7 @@ async def test_basic256_encrypt(srv_crypto_all_certs):
     _, cert = srv_crypto_all_certs
     clt = Client(uri_crypto)
     await clt.set_security_string(
-        f"Basic256Sha256,SignAndEncrypt,{EXAMPLE_PATH}certificate-example.der,{EXAMPLE_PATH}private-key-example.pem,{cert}")
+        f"Basic256Sha256,SignAndEncrypt,{EXAMPLE_PATH / 'certificate-example.der'},{EXAMPLE_PATH / 'private-key-example.pem'},{cert}")
     async with clt:
         assert await clt.nodes.objects.get_children()
 
@@ -157,8 +157,8 @@ async def test_basic256_encrypt_success(srv_crypto_all_certs):
     _, cert = srv_crypto_all_certs
     await clt.set_security(
         security_policies.SecurityPolicyBasic256Sha256,
-        f"{EXAMPLE_PATH}certificate-example.der",
-        f"{EXAMPLE_PATH}private-key-example.pem",
+        f"{EXAMPLE_PATH / 'certificate-example.der'}",
+        f"{EXAMPLE_PATH / 'private-key-example.pem'}",
         None,
         cert,
         ua.MessageSecurityMode.SignAndEncrypt
@@ -172,8 +172,8 @@ async def test_basic256_encrypt_use_certificate_bytes(srv_crypto_all_certs):
     clt = Client(uri_crypto)
     _, cert = srv_crypto_all_certs
     with open(cert, 'rb') as server_cert, \
-            open(f"{EXAMPLE_PATH}certificate-example.der", 'rb') as user_cert, \
-            open(f"{EXAMPLE_PATH}private-key-example.pem", 'rb') as user_key:
+            open(f"{EXAMPLE_PATH / 'certificate-example.der'}", 'rb') as user_cert, \
+            open(f"{EXAMPLE_PATH / 'private-key-example.pem'}", 'rb') as user_key:
         await clt.set_security(
             security_policies.SecurityPolicyBasic256Sha256,
             user_cert.read(),
@@ -195,8 +195,8 @@ async def test_basic256_encrypt_fail(srv_crypto_all_certs):
     with pytest.raises(ua.UaError):
         await clt.set_security(
             security_policies.SecurityPolicyBasic256Sha256,
-            f"{EXAMPLE_PATH}certificate-example.der",
-            f"{EXAMPLE_PATH}private-key-example.pem",
+            f"{EXAMPLE_PATH / 'certificate-example.der'}",
+            f"{EXAMPLE_PATH / 'private-key-example.pem'}",
             None,
             None,
             mode=ua.MessageSecurityMode.None_
@@ -208,8 +208,8 @@ async def test_Aes128Sha256RsaOaep_encrypt_success(srv_crypto_all_certs):
     _, cert = srv_crypto_all_certs
     await clt.set_security(
         security_policies.SecurityPolicyAes128Sha256RsaOaep,
-        f"{EXAMPLE_PATH}certificate-example.der",
-        f"{EXAMPLE_PATH}private-key-example.pem",
+        f"{EXAMPLE_PATH / 'certificate-example.der'}",
+        f"{EXAMPLE_PATH / 'private-key-example.pem'}",
         None,
         cert,
         ua.MessageSecurityMode.SignAndEncrypt

tests/test_permissions.py

-import os
+from pathlib import Path
 import pytest
 
 from asyncua import Client
@@ -24,24 +24,24 @@ port_num3 = 48516
 uri_crypto = "opc.tcp://127.0.0.1:{0:d}".format(port_num1)
 uri_no_crypto = "opc.tcp://127.0.0.1:{0:d}".format(port_num2)
 uri_crypto_cert = "opc.tcp://127.0.0.1:{0:d}".format(port_num3)
-BASE_DIR = os.path.dirname(os.path.dirname(__file__))
-EXAMPLE_PATH = os.path.join(BASE_DIR, "examples") + os.sep
-srv_crypto_params = [(f"{EXAMPLE_PATH}private-key-example.pem",
-                      f"{EXAMPLE_PATH}certificate-example.der"), ]
+BASE_DIR = Path(__file__).parent.parent
+EXAMPLE_PATH = BASE_DIR / "examples"
+srv_crypto_params = [(EXAMPLE_PATH / "private-key-example.pem",
+                      EXAMPLE_PATH / "certificate-example.der"),]
 
 admin_peer_creds = {
-    "certificate": f"{EXAMPLE_PATH}certificates/peer-certificate-example-1.der",
-    "private_key": f"{EXAMPLE_PATH}certificates/peer-private-key-example-1.pem"
+    "certificate": EXAMPLE_PATH / "certificates/peer-certificate-example-1.der",
+    "private_key": EXAMPLE_PATH / "certificates/peer-private-key-example-1.pem"
 }
 
 user_peer_creds = {
-    "certificate": f"{EXAMPLE_PATH}certificates/peer-certificate-example-2.der",
-    "private_key": f"{EXAMPLE_PATH}certificates/peer-private-key-example-2.pem"
+    "certificate": EXAMPLE_PATH / "certificates/peer-certificate-example-2.der",
+    "private_key": EXAMPLE_PATH / "certificates/peer-private-key-example-2.pem"
 }
 
 anonymous_peer_creds = {
-    "certificate": f"{EXAMPLE_PATH}certificates/peer-certificate-example-3.der",
-    "private_key": f"{EXAMPLE_PATH}certificates/peer-private-key-example-3.pem"
+    "certificate": EXAMPLE_PATH / "certificates/peer-certificate-example-3.der",
+    "private_key": EXAMPLE_PATH / "certificates/peer-private-key-example-3.pem"
 }
 
 

tests/test_standard_address_space.py

 import pytest
-import os.path
+from pathlib import Path
 import xml.etree.ElementTree as ET
 
 from asyncua.server.address_space import AddressSpace
@@ -55,7 +55,7 @@ def test_std_address_space_references():
     node_mgt_service = NodeManagementService(aspace)
     standard_address_space.fill_address_space(node_mgt_service)
     std_nodes = read_nodes(
-        os.path.abspath(os.path.join(os.path.dirname(__file__), '..', 'schemas', 'Opc.Ua.NodeSet2.xml'))
+        Path(__file__).parent.parent.absolute() / 'schemas' / 'Opc.Ua.NodeSet2.xml'
     )
     for k in aspace.keys():
         refs = set(

tests/test_sync.py

 from concurrent.futures import Future
-import os
+from pathlib import Path
 import tempfile
 
 import pytest
@@ -134,7 +134,7 @@ def test_sync_xml_export(server):
     exp = XmlExporter(server)
     exp.build_etree([server.nodes.objects])
     with tempfile.TemporaryDirectory() as tmpdir:
-        exp.write_xml(os.path.join(tmpdir, "toto_test_export.xml"))
+        exp.write_xml(Path(tmpdir) / "toto_test_export.xml")
 
 
 def test_create_enum_sync(server):

tests/test_unit.py

@@ -5,7 +5,7 @@ Simple unit test that do not need to setup a server or a client
 """
 
 import io
-import os
+from pathlib import Path
 import uuid
 import pytest
 import logging
@@ -27,7 +27,7 @@ from asyncua.ua.uatypes import _MaskEnum
 from asyncua.common.structures import StructGenerator
 from asyncua.common.connection import MessageChunk
 
-EXAMPLE_BSD_PATH = os.path.abspath(os.path.join(os.path.dirname(__file__), "example.bsd"))
+EXAMPLE_BSD_PATH = Path(__file__).parent.absolute() / "example.bsd"
 
 
 def test_variant_array_none():

tests/util_enum_struct.py

-import os
 from dataclasses import dataclass
+from enum import IntEnum
+from pathlib import Path
 
-from asyncua import ua
+from asyncua import Server, ua
 from asyncua.ua import uatypes
-from enum import IntEnum
-from asyncua import Server
 
-TEST_DIR = os.path.dirname(__file__) + os.sep
+TEST_DIR = Path(__file__).parent
 
 
 class ExampleEnum(IntEnum):
@@ -28,7 +27,7 @@ class ExampleStruct:
 
 async def add_server_custom_enum_struct(server: Server):
     # import some nodes from xml
-    await server.import_xml(f"{TEST_DIR}enum_struct_test_nodes.xml")
+    await server.import_xml(TEST_DIR / "enum_struct_test_nodes.xml")
     ns = await server.get_namespace_index('http://yourorganisation.org/struct_enum_example/')
     uatypes.register_extension_object('ExampleStruct', ua.NodeId(5001, ns), ExampleStruct)
     val = ua.ExampleStruct()

tools/uacall

 #!/usr/bin/env python3
 
 import sys
-import os
-sys.path.append(os.path.join(os.path.dirname(os.path.realpath(__file__)), ".."))
+from pathlib import Path
 
-from asyncua.tools import uacall
+sys.path.append(f'{Path(__file__).parent.parent}')
 
+from asyncua.tools import uacall
 
 if __name__ == "__main__":
     uacall()

tools/uaclient

 #!/usr/bin/env python
 
 import sys
-import os
-sys.path.append(os.path.join(os.path.dirname(os.path.realpath(__file__)), ".."))
+from pathlib import Path
+
+sys.path.append(f'{Path(__file__).parent.parent}')
 
 from asyncua.tools import uaclient
 

tools/uadiscover

 #!/usr/bin/env python3
 
 import sys
-import os
-sys.path.append(os.path.join(os.path.dirname(os.path.realpath(__file__)), ".."))
+from pathlib import Path
+
+sys.path.append(f'{Path(__file__).parent.parent}')
 
 from asyncua.tools import uadiscover
 

tools/uahistoryread

 #!/usr/bin/env python
 
 import sys
-import os
-sys.path.append(os.path.join(os.path.dirname(os.path.realpath(__file__)), ".."))
+from pathlib import Path
+
+sys.path.append(f'{Path(__file__).parent.parent}')
 
 from asyncua.tools import uahistoryread
 

tools/uals

 #!/usr/bin/env python3
 
 import sys
-import os
-sys.path.append(os.path.join(os.path.dirname(os.path.realpath(__file__)), ".."))
+from pathlib import Path
+
+sys.path.append(f'{Path(__file__).parent.parent}')
 
 from asyncua.tools import uals
 

tools/uaread

 #!/usr/bin/env python3
 
 import sys
-import os
-sys.path.append(os.path.join(os.path.dirname(os.path.realpath(__file__)), ".."))
+from pathlib import Path
+
+sys.path.append(f'{Path(__file__).parent.parent}')
 
 from asyncua.tools import uaread
 

tools/uaserver

 #!/usr/bin/env python3
 
-import sys
-import os
 import logging
+import sys
+from pathlib import Path
+
 logging.basicConfig(level=logging.DEBUG)
-sys.path.append(os.path.join(os.path.dirname(os.path.realpath(__file__)), ".."))
+sys.path.append(f'{Path(__file__).parent.parent}')
 
 from asyncua.tools import uaserver
 
-
 if __name__ == "__main__":
     uaserver()

tools/uasubscribe

 #!/usr/bin/env python3
 
 import sys
-import os
-sys.path.append(os.path.join(os.path.dirname(os.path.realpath(__file__)), ".."))
+from pathlib import Path
+
+sys.path.append(f'{Path(__file__).parent.parent}')
 
 from asyncua.tools import uasubscribe
 

tools/uawrite

 #!/usr/bin/env python3
 
 import sys
-import os
-sys.path.append(os.path.join(os.path.dirname(os.path.realpath(__file__)), ".."))
+from pathlib import Path
+
+sys.path.append(f'{Path(__file__).parent.parent}')
 
 from asyncua.tools import uawrite