Added proper error messages for when the project needs Attract setup.

When the 'shot' node type doesn't exist, we now show an error message
about this (instead of causing an IndexError).

blender_cloud/attract/__init__.py

@@ -106,7 +106,25 @@ class ToolsPanel(Panel):
         layout.operator('attract.shots_order_update')
 
 
-class AttractShotSubmitNew(Operator):
+class AttractOperatorMixin:
+    """Mix-in class for all Attract operators."""
+
+    def _project_needs_setup_error(self):
+        self.report({'ERROR'}, 'Your Blender Cloud project is not set up for Attract.')
+        return {'CANCELLED'}
+
+    def find_node_type(self, node_type_name: str) -> 'pillarsdk.NodeType':
+        from .. import pillar
+
+        node_type_list = pillar.call(NodeType.all, {'where': "name=='%s'" % node_type_name})
+        if not node_type_list._items:
+            return self._project_needs_setup_error()
+
+        node_type = node_type_list._items[0]
+        return node_type
+
+
+class AttractShotSubmitNew(AttractOperatorMixin, Operator):
     bl_idname = "attract.shot_submit_new"
     bl_label = "Submit to Attract"
 
@@ -116,17 +134,17 @@ class AttractShotSubmitNew(Operator):
         return not strip.atc_object_id
 
     def execute(self, context):
-        from blender_cloud import pillar
+        from .. import pillar
         import blender_id
 
         strip = active_strip(context)
         if strip.atc_object_id:
             return
 
-        # Filter the NodeType collection, but it's still a list
-        node_type_list = pillar.call(NodeType.all, {'where': "name=='shot'"})
-        # Get the 'shot' node type
-        node_type = node_type_list['_items'][0]
+        node_type = self.find_node_type('shot')
+        if isinstance(node_type, set):  # in case of error
+            return node_type
+
         # Define the shot properties
         prop = {'name': strip.name,
                 'description': '',
@@ -156,7 +174,7 @@ class AttractShotSubmitNew(Operator):
         return {'FINISHED'}
 
 
-class AttractShotRelink(Operator):
+class AttractShotRelink(AttractOperatorMixin, Operator):
     bl_idname = "attract.shot_relink"
     bl_label = "Relink to Attract"
     strip_atc_object_id = bpy.props.StringProperty()
@@ -190,7 +208,7 @@ class AttractShotRelink(Operator):
         col.prop(self, 'strip_atc_object_id', text='Shot ID')
 
 
-class AttractShotSubmitUpdate(Operator):
+class AttractShotSubmitUpdate(AttractOperatorMixin, Operator):
     bl_idname = 'attract.shot_submit_update'
     bl_label = 'Update'
     bl_description = 'Syncronizes local and remote changes'
@@ -211,7 +229,7 @@ class AttractShotSubmitUpdate(Operator):
         return {'FINISHED'}
 
 
-class AttractShotDelete(Operator):
+class AttractShotDelete(AttractOperatorMixin, Operator):
     bl_idname = 'attract.shot_delete'
     bl_label = 'Delete'
     bl_description = 'Remove from Attract'
@@ -224,7 +242,7 @@ class AttractShotDelete(Operator):
         return {'FINISHED'}
 
 
-class AttractStripUnlink(Operator):
+class AttractStripUnlink(AttractOperatorMixin, Operator):
     bl_idname = 'attract.strip_unlink'
     bl_label = 'Unlink'
     bl_description = 'Remove Attract props from the strip'
@@ -235,7 +253,7 @@ class AttractStripUnlink(Operator):
         return {'FINISHED'}
 
 
-class AttractShotsOrderUpdate(Operator):
+class AttractShotsOrderUpdate(AttractOperatorMixin, Operator):
     bl_idname = 'attract.shots_order_update'
     bl_label = 'Update shots order'
 
@@ -244,8 +262,9 @@ class AttractShotsOrderUpdate(Operator):
 
         # Get all shot nodes from server, build dictionary using ObjectID
         # as indexes
-        node_type_list = pillar.call(NodeType.all, {'where': "name=='shot'"})
-        node_type = node_type_list._items[0]
+        node_type = self.find_node_type('shot')
+        if isinstance(node_type, set):  # in case of error
+            return node_type
 
         shots = pillar.call(Node.all, {
             'where': {'node_type': node_type._id},