feat(Blenvy:Blender): finally ! added a clean way of dealing with failed gltf exports

* no more re-raised errors
 * no more remaining "___temp_scenes" or object renames aka no more breaking user's blend files
 * also added boilerplate for displaying more accurate traceback & used it to still display the export errors correctly

TODO.md

@@ -340,5 +340,6 @@ Bevy Side:
         - [ ] the ability to map external TEXT files to data in BLender (git-able, hand editable)
 - [x] make aabbs calculation non configurable, getting rid of the last setting (for now)
 - [ ] add information & screenshots about adding assets to the Blender add-on docs
+- [x] finally deal cleanly with gltf export failures & make sure to always reset the state of the blend file
 
 clear && pytest -svv --blender-template ../../testing/bevy_example/art/testing_library.blend --blender-executable /home/ckaos/tools/blender/blender-4.1.0-linux-x64/blender tests/test_bevy_integration_prepare.py  && pytest -svv --blender-executable /home/ckaos/tools/blender/blender-4.1.0-linux-x64/blender tests/test_bevy_integration.py

tools/blenvy/add_ons/auto_export/common/export_gltf.py

@@ -83,3 +83,4 @@ def export_gltf (path, gltf_export_settings):
     # print("export settings",settings)
     os.makedirs(os.path.dirname(path), exist_ok=True)
     bpy.ops.export_scene.gltf(**settings)
+

tools/blenvy/add_ons/auto_export/common/generate_temporary_scene_and_export.py

@@ -1,13 +1,11 @@
-import json
 import bpy
 from blenvy.core.helpers_collections import (set_active_collection)
 from blenvy.core.object_makers import (make_empty)
 from .duplicate_object import duplicate_object
 from .export_gltf import export_gltf
-from blenvy.core.scene_helpers import add_scene_property
 from ..constants import custom_properties_to_filter_out
 from ..utils import remove_unwanted_custom_properties
-
+from ....core.utils import exception_traceback, show_message_box
 
 """ 
 generates a temporary scene, fills it with data, cleans up after itself
@@ -52,22 +50,23 @@ def generate_temporary_scene_and_export(settings, gltf_export_settings, gltf_out
         # detect scene mistmatch
         scene_mismatch = bpy.context.scene.name != bpy.context.window.scene.name
         if scene_mismatch:
-            raise Exception("Context scene mismatch, aborting", bpy.context.scene.name, bpy.context.window.scene.name)
-        
-        set_active_collection(bpy.context.scene, temp_root_collection.name)
-        # generate contents of temporary scene
-        scene_filler_data = tempScene_filler(temp_root_collection)
-        # export the temporary scene
-        try:
-            print("dry_run MODE", settings.auto_export.dry_run)
-            if settings.auto_export.dry_run == "DISABLED":
-                export_gltf(gltf_output_path, gltf_export_settings)
-        except Exception as error:
-            print("failed to export gltf !", error) 
-            raise error
-        finally:
-            # restore everything
-            tempScene_cleaner(temp_scene, scene_filler_data)
+            show_message_box("Error in Gltf Exporter", icon="ERROR", lines=[f"Context scene mismatch, aborting: {bpy.context.scene.name} vs {bpy.context.window.scene.name}"])
+        else:
+            set_active_collection(bpy.context.scene, temp_root_collection.name)
+            # generate contents of temporary scene
+            scene_filler_data = tempScene_filler(temp_root_collection)
+            # export the temporary scene
+            try:
+                print("dry_run MODE", settings.auto_export.dry_run)
+                if settings.auto_export.dry_run == "DISABLED":           
+                    export_gltf(gltf_output_path, gltf_export_settings)
+            except Exception as error:
+                print("failed to export gltf !", error) 
+                show_message_box("Error in Gltf Exporter", icon="ERROR", lines=exception_traceback(error))
+            finally:
+                print("restoring state of scene")
+                # restore everything
+                tempScene_cleaner(temp_scene, scene_filler_data)
 
     # reset active scene
     bpy.context.window.scene = active_scene

tools/blenvy/core/utils.py

@@ -0,0 +1,33 @@
+import sys
+import inspect
+import bpy
+
+def full_stack_lines(tb=None):
+    text = []
+    try:
+        if tb is None:
+            tb = sys.exc_info()[2]
+
+        text.append('Traceback (most recent call last):')
+        for item in reversed(inspect.getouterframes(tb.tb_frame)[1:]):
+            text.append('   File "{1}", line {2}, in {3}\n'.format(*item))
+            for line in item[4]:
+                text.append('       ' + line.lstrip())
+        for item in inspect.getinnerframes(tb):
+            text.append('   File "{1}", line {2}, in {3}\n'.format(*item))
+            for line in item[4]:
+                text.append('       ' + line.lstrip())
+    except: pass
+    return text
+
+def exception_traceback(error):
+    traceback_formated = [str(error)]
+    traceback_formated += full_stack_lines()
+    return traceback_formated
+
+def show_message_box(title = "Message Box", icon = 'INFO', lines=""):
+    myLines=lines
+    def draw(self, context):
+        for n in myLines:
+            self.layout.label(text=n)
+    bpy.context.window_manager.popup_menu(draw, title = title, icon = icon)