Clean up workarounds for older Python versions

Now that 3.9 is our lower limit, we can drop some code that was catering
older Python versions.

Signed-off-by: Jan Kiszka <[email protected]>

kas/attestation.py

@@ -108,10 +108,9 @@ def _make_relative_path(self, path: Path):
         top_repo_path = Path(self._ctx.config.handler.get_top_repo_path())
         workdir = Path(self._ctx.kas_work_dir)
 
-        # is_relative_to implementation for python < 3.9
-        try:
+        if path.is_relative_to(workdir):
             return path.relative_to(workdir)
-        except ValueError:
+        else:
             return path.relative_to(top_repo_path)
 
     def type_(self):

kas/context.py

@@ -23,33 +23,20 @@
     This module contains the implementation of the kas context.
 """
 
+import distro
 import os
 import logging
 from enum import Enum
 from kas.kasusererror import KasUserError
 
-try:
-    import distro
-
-    def get_distro_id_base():
-        """
-            Returns a compatible distro id.
-        """
-        return distro.like() or distro.id()
-
-except ImportError:
-    import platform
-
-    def get_distro_id_base():
-        """
-            Wrapper around platform.dist to simulate distro.id
-            platform.dist is deprecated and will be removed in python 3.7
-            Use the 'distro' package instead.
-        """
-        return platform.dist()[0]
+__context__ = None
 
 
-__context__ = None
+def get_distro_id_base():
+    """
+        Returns a compatible distro id.
+    """
+    return distro.like() or distro.id()
 
 
 def create_global_context(args):

kas/kas.py

@@ -85,14 +85,6 @@ def cleanup_logger():
             logging.root.removeHandler(handler)
 
 
-def get_pending_tasks(loop):
-    try:
-        return asyncio.all_tasks(loop)
-    except AttributeError:
-        # for Python < 3.7
-        return asyncio.Task.all_tasks(loop)
-
-
 def interruption():
     """
         Gracefully cancel all tasks in the event loop
@@ -101,7 +93,7 @@ def interruption():
     for sig in [signal.SIGINT, signal.SIGTERM]:
         loop.remove_signal_handler(sig)
         loop.add_signal_handler(sig, termination)
-    pending = get_pending_tasks(loop)
+    pending = asyncio.all_tasks(loop)
     if pending:
         logging.debug(f'waiting for {len(pending)} tasks to terminate')
     [t.cancel() for t in pending]
@@ -119,13 +111,8 @@ def shutdown_loop(loop):
     """
         Waits for completion of the event loop
     """
-    pending = get_pending_tasks(loop)
-    # Ignore exceptions in final shutdown (Python3.6 workaround).
-    # These are related to the cancellation of tasks.
-    try:
-        loop.run_until_complete(asyncio.gather(*pending))
-    except KasUserError:
-        pass
+    pending = asyncio.all_tasks(loop)
+    loop.run_until_complete(asyncio.gather(*pending))
     loop.close()
 
 

kas/libcmds.py

@@ -27,7 +27,6 @@
 import logging
 import shutil
 import os
-import sys
 import pprint
 import configparser
 import json
@@ -550,11 +549,7 @@ def execute(self, ctx):
         # now fetch everything with complete config
         repos_fetch(ctx.config.get_repos())
 
-        if sys.version_info < (3, 8):
-            config_str = pprint.pformat(ctx.config.get_config())
-        else:
-            config_str = pprint.pformat(ctx.config.get_config(),
-                                        sort_dicts=False)
+        config_str = pprint.pformat(ctx.config.get_config(), sort_dicts=False)
         logging.debug('Configuration from config file:\n%s', config_str)
 
 

kas/libkas.py

@@ -120,12 +120,8 @@ async def run_cmd_async(cmd, cwd, env=None, fail=True, liveupdate=False):
 
     logo = LogOutput(liveupdate)
 
-    try:
-        orig_fd = signal.set_wakeup_fd(-1, warn_on_full_buffer=False)
-        signal.set_wakeup_fd(orig_fd, warn_on_full_buffer=False)
-    except TypeError:
-        # Python < 3.7 - we tried our best
-        pass
+    orig_fd = signal.set_wakeup_fd(-1, warn_on_full_buffer=False)
+    signal.set_wakeup_fd(orig_fd, warn_on_full_buffer=False)
 
     try:
         process = await asyncio.create_subprocess_exec(

kas/repos.py

@@ -25,7 +25,6 @@
 
 import re
 import os
-import sys
 import linecache
 import logging
 import shutil
@@ -35,11 +34,7 @@
 from .context import get_context
 from .libkas import run_cmd_async, run_cmd
 from .kasusererror import KasUserError
-
-if sys.version_info < (3, 8):
-    from cached_property import cached_property
-else:
-    from functools import cached_property
+from functools import cached_property
 
 __license__ = 'MIT'
 __copyright__ = 'Copyright (c) Siemens AG, 2017-2018'
@@ -327,9 +322,6 @@ async def fetch_async(self):
                 logging.debug('Created repo ref for %s', self.qualified_name)
                 try:
                     os.rename(tmpdir, sdir)
-                    if sys.version_info < (3, 8):
-                        # recreate dir so cleanup handler can delete it
-                        os.makedirs(tmpdir, exist_ok=True)
                 except OSError:
                     logging.debug('repo %s already cloned by other instance',
                                   self.qualified_name)