Delete global ID when deleting post. Cache model's content XML tag into global ID

boards/models/post/sync.py

@@ -55,15 +55,19 b' class SyncManager:'
 
         models = et.SubElement(response, TAG_MODELS)
 
-        # TODO Put global id's content into XML instad of manual serialization
         for post in model_list:
             model = et.SubElement(models, TAG_MODEL)
             model.set(ATTR_NAME, 'post')
 
+            global_id = post.global_id
+
+            if global_id.content:
+                model.append(et.fromstring(global_id.content))
+            else:
             content_tag = et.SubElement(model, TAG_CONTENT)
 
             tag_id = et.SubElement(content_tag, TAG_ID)
-            post.global_id.to_xml_element(tag_id)
+                global_id.to_xml_element(tag_id)
 
             title = et.SubElement(content_tag, TAG_TITLE)
             title.text = post.title
@@ -100,17 +104,20 b' class SyncManager:'
                         attachments_tag, attachment_refs, file.file.file,
                         file.hash, file.file.url)
 
+                global_id.content = et.tostring(content_tag, ENCODING_UNICODE)
+                global_id.save()
+
             signatures_tag = et.SubElement(model, TAG_SIGNATURES)
-            post_signatures = post.global_id.signature_set.all()
+            post_signatures = global_id.signature_set.all()
             if post_signatures:
                 signatures = post_signatures
             else:
-                key = KeyPair.objects.get(public_key=post.global_id.key)
+                key = KeyPair.objects.get(public_key=global_id.key)
                 signature = Signature(
                     key_type=key.key_type,
                     key=key.public_key,
-                    signature=key.sign(et.tostring(content_tag, encoding=ENCODING_UNICODE)),
-                    global_id=post.global_id,
+                    signature=key.sign(global_id.content),
+                    global_id=global_id,
                 )
                 signature.save()
                 signatures = [signature]
@@ -140,7 +147,7 b' class SyncManager:'
                 if exists:
                     print('Post with same ID already exists')
                 else:
-                    global_id.content = et.to_string(tag_content,
+                    global_id.content = et.tostring(tag_content,
                             ENCODING_UNICODE)
                     global_id.save()
                     for signature in signatures:

boards/models/signature.py

@@ -64,6 +64,12 b' class GlobalIdManager(models.Manager):'
 
 
 class GlobalId(models.Model):
+    """
+    Global model ID and cache.
+    Key, key type and local ID make a single global identificator of the model.
+    Content is an XML cache of the model that can be passed along between nodes
+    without manual serialization each time.
+    """
     class Meta:
         app_label = 'boards'
 

boards/signals.py

@@ -79,3 +79,9 b' def update_thread_on_delete(instance, **'
     thread = instance.get_thread()
     thread.last_edit_time = timezone.now()
     thread.save()
+
+
+@receiver(post_delete, sender=Post)
+def delete_global_id(instance, **kwargs):
+    if instance.global_id and instance.global_id.id:
+        instance.global_id.delete()