Add group_id and fix remove printer

CURA-6483

 - Added a unique group_id (a GUID) to all created GlobalStack.
 - Changed version upgrade to generate unique group_ids for
   GlobalStacks.
 - RemoveMachine() now uses group_ids to remove hidden GlobalStacks.

cura/Settings/GlobalStack.py

@@ -4,6 +4,8 @@
 from collections import defaultdict
 import threading
 from typing import Any, Dict, Optional, Set, TYPE_CHECKING, List
+import uuid
+
 from PyQt5.QtCore import pyqtProperty, pyqtSlot, pyqtSignal
 
 from UM.Decorators import override
@@ -33,6 +35,7 @@ class GlobalStack(CuraContainerStack):
         super().__init__(container_id)
 
         self.setMetaDataEntry("type", "machine")  # For backward compatibility
+        self.setMetaDataEntry("group_id", str(uuid.uuid4()))  # Assign a new GlobalStack to a unique group by default
 
         self._extruders = {}  # type: Dict[str, "ExtruderStack"]
 

cura/Settings/MachineManager.py

@@ -797,7 +797,6 @@ class MachineManager(QObject):
                 self.setActiveMachine(other_machine_stacks[0]["id"])
 
         metadata = CuraContainerRegistry.getInstance().findContainerStacksMetadata(id = machine_id)[0]
-        network_key = metadata.get("um_network_key", None)
         ExtruderManager.getInstance().removeMachineExtruders(machine_id)
         containers = CuraContainerRegistry.getInstance().findInstanceContainersMetadata(type = "user", machine = machine_id)
         for container in containers:
@@ -805,8 +804,9 @@ class MachineManager(QObject):
         CuraContainerRegistry.getInstance().removeContainer(machine_id)
 
         # If the printer that is being removed is a network printer, the hidden printers have to be also removed
-        if network_key:
-            metadata_filter = {"um_network_key": network_key}
+        group_id = metadata.get("group_id", None)
+        if group_id:
+            metadata_filter = {"group_id": group_id}
             hidden_containers = CuraContainerRegistry.getInstance().findContainerStacks(type = "machine", **metadata_filter)
             if hidden_containers:
                 # This reuses the method and remove all printers recursively
@@ -1366,6 +1366,7 @@ class MachineManager(QObject):
             new_machine = CuraStackBuilder.createMachine(machine_definition_id + "_sync", machine_definition_id)
             if not new_machine:
                 return
+            new_machine.setMetaDataEntry("group_id", self._global_container_stack.getMetaDataEntry("group_id"))
             new_machine.setMetaDataEntry("um_network_key", self.activeMachineNetworkKey())
             new_machine.setMetaDataEntry("group_name", self.activeMachineNetworkGroupName)
             new_machine.setMetaDataEntry("hidden", False)

plugins/VersionUpgrade/VersionUpgrade40to41/VersionUpgrade40to41.py

@@ -3,6 +3,7 @@
 
 import configparser
 import io
+import uuid
 from typing import Dict, List, Tuple
 
 from UM.VersionUpgrade import VersionUpgrade
@@ -18,6 +19,7 @@ _renamed_quality_profiles = {
     "gmax15plus_pla_very_thick": "gmax15plus_global_very_thick"
 } # type: Dict[str, str]
 
+
 ##  Upgrades configurations from the state they were in at version 4.0 to the
 #   state they should be in at version 4.1.
 class VersionUpgrade40to41(VersionUpgrade):
@@ -95,6 +97,13 @@ class VersionUpgrade40to41(VersionUpgrade):
         if parser["containers"]["4"] in _renamed_quality_profiles:
             parser["containers"]["4"] = _renamed_quality_profiles[parser["containers"]["4"]]
 
+        # Assign a GlobalStack to a unique group_id. If the GlobalStack has a UM network connection, use the UM network
+        # key as the group_id.
+        if "um_network_key" in parser["metadata"]:
+            parser["metadata"]["group_id"] = parser["metadata"]["um_network_key"]
+        elif "group_id" not in parser["metadata"]:
+            parser["metadata"]["group_id"] = str(uuid.uuid4())
+
         result = io.StringIO()
         parser.write(result)
         return [filename], [result.getvalue()]