launchd: Handle deprecated APIs in plistlib (#1554)

Co-authored-by: Felix Fontein <felix@fontein.de>

changelogs/fragments/1552_launchd.yml

@@ -0,0 +1,2 @@
+bugfixes:
+- launchd - handle deprecated APIs like ``readPlist`` and ``writePlist`` in ``plistlib`` (https://github.com/ansible-collections/community.general/issues/1552).

plugins/modules/system/launchd.py

@@ -114,6 +114,7 @@ from abc import ABCMeta, abstractmethod
 from time import sleep
 
 from ansible.module_utils.basic import AnsibleModule
+from ansible.module_utils._text import to_native
 
 
 class ServiceState:
@@ -142,6 +143,9 @@ class Plist:
 
         state, pid, dummy, dummy = LaunchCtlList(module, service).run()
 
+        # Check if readPlist is available or not
+        self.old_plistlib = hasattr(plistlib, 'readPlist')
+
         self.__file = self.__find_service_plist(service)
         if self.__file is None:
             msg = 'Unable to infer the path of %s service plist file' % service
@@ -150,7 +154,8 @@ class Plist:
             module.fail_json(msg=msg)
         self.__update(module)
 
-    def __find_service_plist(self, service_name):
+    @staticmethod
+    def __find_service_plist(service_name):
         """Finds the plist file associated with a service"""
 
         launchd_paths = [
@@ -176,9 +181,38 @@ class Plist:
         self.__handle_param_enabled(module)
         self.__handle_param_force_stop(module)
 
+    def __read_plist_file(self, module):
+        service_plist = {}
+        if self.old_plistlib:
+            return plistlib.readPlist(self.__file)
+
+        # readPlist is deprecated in Python 3 and onwards
+        try:
+            with open(self.__file, 'rb') as plist_fp:
+                service_plist = plistlib.load(plist_fp)
+        except Exception as e:
+            module.fail_json(msg="Failed to read plist file "
+                                 "%s due to %s" % (self.__file, to_native(e)))
+        return service_plist
+
+    def __write_plist_file(self, module, service_plist=None):
+        if not service_plist:
+            service_plist = {}
+
+        if self.old_plistlib:
+            plistlib.writePlist(service_plist, self.__file)
+            return
+        # writePlist is deprecated in Python 3 and onwards
+        try:
+            with open(self.__file, 'wb') as plist_fp:
+                plistlib.dump(service_plist, plist_fp)
+        except Exception as e:
+            module.fail_json(msg="Failed to write to plist file "
+                                 " %s due to %s" % (self.__file, to_native(e)))
+
     def __handle_param_enabled(self, module):
         if module.params['enabled'] is not None:
-            service_plist = plistlib.readPlist(self.__file)
+            service_plist = self.__read_plist_file(module)
 
             # Enable/disable service startup at boot if requested
             # Launchctl does not expose functionality to set the RunAtLoad
@@ -191,12 +225,12 @@ class Plist:
 
                     # Update the plist with one of the changes done.
                     if not module.check_mode:
-                        plistlib.writePlist(service_plist, self.__file)
+                        self.__write_plist_file(module, service_plist)
                         self.__changed = True
 
     def __handle_param_force_stop(self, module):
         if module.params['force_stop'] is not None:
-            service_plist = plistlib.readPlist(self.__file)
+            service_plist = self.__read_plist_file(module)
 
             # Set KeepAlive to false in case force_stop is defined to avoid
             # that the service gets restarted when stopping was requested.
@@ -207,7 +241,7 @@ class Plist:
 
                     # Update the plist with one of the changes done.
                     if not module.check_mode:
-                        plistlib.writePlist(service_plist, self.__file)
+                        self.__write_plist_file(module, service_plist)
                         self.__changed = True
 
     def is_changed(self):
@@ -325,7 +359,7 @@ class LaunchCtlStart(LaunchCtlTask):
     def runCommand(self):
         state, dummy, dummy, dummy = self.get_state()
 
-        if state == ServiceState.STOPPED or state == ServiceState.LOADED:
+        if state in (ServiceState.STOPPED, ServiceState.LOADED):
             self.reload()
             self.start()
         elif state == ServiceState.STARTED:
@@ -361,7 +395,7 @@ class LaunchCtlStop(LaunchCtlTask):
             if self._plist.is_changed():
                 self.reload()
                 self.stop()
-        elif state == ServiceState.STARTED or state == ServiceState.LOADED:
+        elif state in (ServiceState.STARTED, ServiceState.LOADED):
             if self._plist.is_changed():
                 self.reload()
             self.stop()