Ensure that post processing scripts are correctly reloaded on project loading

Previously it would not re load post processing plugins if it was updating an existing machine

Fixes #6881

plugins/3MFReader/ThreeMFWorkspaceReader.py

@@ -1005,7 +1005,6 @@ class ThreeMFWorkspaceReader(WorkspaceReader):
 
         # Set metadata fields that are missing from the global stack
         for key, value in self._machine_info.metadata_dict.items():
-            if key not in global_stack.getMetaData():
             global_stack.setMetaDataEntry(key, value)
 
     def _updateActiveMachine(self, global_stack):

plugins/PostProcessingPlugin/PostProcessingPlugin.py

@@ -44,6 +44,9 @@ class PostProcessingPlugin(QObject, Extension):
         # There can be duplicates, which will be executed in sequence.
         self._script_list = []  # type: List[Script]
         self._selected_script_index = -1
+        self._global_container_stack = Application.getInstance().getGlobalContainerStack()
+        if self._global_container_stack:
+            self._global_container_stack.metaDataChanged.connect(self._restoreScriptInforFromMetadata)
 
         Application.getInstance().getOutputDeviceManager().writeStarted.connect(self.execute)
         Application.getInstance().globalContainerStackChanged.connect(self._onGlobalContainerStackChanged)  # When the current printer changes, update the list of scripts.
@@ -209,11 +212,9 @@ class PostProcessingPlugin(QObject, Extension):
         self.scriptListChanged.emit()
         self._propertyChanged()
 
-    ##  When the global container stack is changed, swap out the list of active
+    def _restoreScriptInforFromMetadata(self):
-    #   scripts.
-    def _onGlobalContainerStackChanged(self) -> None:
         self.loadAllScripts()
-        new_stack = Application.getInstance().getGlobalContainerStack()
+        new_stack = self._global_container_stack
         if new_stack is None:
             return
         self._script_list.clear()
@@ -224,7 +225,8 @@ class PostProcessingPlugin(QObject, Extension):
 
         self._script_list.clear()
         scripts_list_strs = new_stack.getMetaDataEntry("post_processing_scripts")
-        for script_str in scripts_list_strs.split("\n"):  # Encoded config files should never contain three newlines in a row. At most 2, just before section headers.
+        for script_str in scripts_list_strs.split(
+                "\n"):  # Encoded config files should never contain three newlines in a row. At most 2, just before section headers.
             if not script_str:  # There were no scripts in this one (or a corrupt file caused more than 3 consecutive newlines here).
                 continue
             script_str = script_str.replace(r"\\\n", "\n").replace(r"\\\\", "\\\\")  # Unescape escape sequences.
@@ -235,7 +237,9 @@ class PostProcessingPlugin(QObject, Extension):
                 if script_name == "DEFAULT":  # ConfigParser always has a DEFAULT section, but we don't fill it. Ignore this one.
                     continue
                 if script_name not in self._loaded_scripts:  # Don't know this post-processing plug-in.
-                    Logger.log("e", "Unknown post-processing script {script_name} was encountered in this global stack.".format(script_name = script_name))
+                    Logger.log("e",
+                               "Unknown post-processing script {script_name} was encountered in this global stack.".format(
+                                   script_name=script_name))
                     continue
                 new_script = self._loaded_scripts[script_name]()
                 new_script.initialize()
@@ -245,7 +249,22 @@ class PostProcessingPlugin(QObject, Extension):
                 self._script_list.append(new_script)
 
         self.setSelectedScriptIndex(0)
+        # Ensure that we always force an update (otherwise the fields don't update correctly!)
+        self.selectedIndexChanged.emit()
         self.scriptListChanged.emit()
+        self._propertyChanged()
+
+    ##  When the global container stack is changed, swap out the list of active
+    #   scripts.
+    def _onGlobalContainerStackChanged(self) -> None:
+        if self._global_container_stack:
+            self._global_container_stack.metaDataChanged.disconnect(self._restoreScriptInforFromMetadata)
+
+        self._global_container_stack = Application.getInstance().getGlobalContainerStack()
+
+        if self._global_container_stack:
+            self._global_container_stack.metaDataChanged.connect(self._restoreScriptInforFromMetadata)
+        self._restoreScriptInforFromMetadata()
 
     @pyqtSlot()
     def writeScriptsToStack(self) -> None:
@@ -267,14 +286,18 @@ class PostProcessingPlugin(QObject, Extension):
 
         script_list_string = "\n".join(script_list_strs)  # ConfigParser should never output three newlines in a row when serialised, so it's a safe delimiter.
 
-        global_stack = Application.getInstance().getGlobalContainerStack()
+        if self._global_container_stack is None:
-        if global_stack is None:
             return
 
-        if "post_processing_scripts" not in global_stack.getMetaData():
+        # Ensure we don't get triggered by our own write.
-            global_stack.setMetaDataEntry("post_processing_scripts", "")
+        self._global_container_stack.metaDataChanged.disconnect(self._restoreScriptInforFromMetadata)
 
-        global_stack.setMetaDataEntry("post_processing_scripts", script_list_string)
+        if "post_processing_scripts" not in self._global_container_stack.getMetaData():
+            self._global_container_stack.setMetaDataEntry("post_processing_scripts", "")
+
+        self._global_container_stack.setMetaDataEntry("post_processing_scripts", script_list_string)
+        # We do want to listen to other events.
+        self._global_container_stack.metaDataChanged.connect(self._restoreScriptInforFromMetadata)
 
     ##  Creates the view used by show popup. The view is saved because of the fairly aggressive garbage collection.
     def _createView(self) -> None: