Added content field to global id to store cached model content. If a server uses diffrent serialization algorithm, it would still pass the same content string along saving its signature

boards/migrations/0044_globalid_content.py

@@ -0,0 +1,20 b''
+# -*- coding: utf-8 -*-
+# Generated by Django 1.9.5 on 2016-05-04 15:36
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('boards', '0043_merge'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='globalid',
+            name='content',
+            field=models.TextField(blank=True, null=True),
+        ),
+    ]

boards/models/post/sync.py

@@ -55,6 +55,7 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')
@@ -139,6 +140,8 b' class SyncManager:'
                 if exists:
                     print('Post with same ID already exists')
                 else:
+                    global_id.content = et.to_string(tag_content,
+                            ENCODING_UNICODE)
                     global_id.save()
                     for signature in signatures:
                         signature.global_id = global_id

boards/models/signature.py

@@ -80,6 +80,7 b' class GlobalId(models.Model):'
     key = models.TextField()
     key_type = models.TextField()
     local_id = models.IntegerField()
+    content = models.TextField(blank=True, null=True)
 
     def __str__(self):
         return '%s::%s::%d' % (self.key_type, self.key, self.local_id)