delete files before save new

ippisite/ippidb/models/targetcentric.py

@@ -5,7 +5,7 @@ from django.dispatch import receiver
 from django.db.models.signals import pre_delete, post_save, pre_save
 from .ippidb import Protein
 from ippidb.ws import convert_pdb_ligand_id_to_iupacandsmiles
-import json
+import json, os
 
 
 def content(instance, filename):
@@ -527,7 +527,29 @@ def interactdelete(sender, instance, **kwargs):
             ):
                 interactfile.interact_file.delete()
 
-
 @receiver(pre_save, sender=Chain)
 def updatemrcfile(sender, instance, **kwargs):
-    print(instance.mrc_file.path, kwargs)
+    try:
+        old_chain = sender.objects.get(id=instance.id)
+    except sender.DoesNotExist:
+        old_chain = None
+    if instance.mrc_file:
+        if old_chain:
+            if old_chain.mrc_file:
+                path_mrc_file = old_chain.mrc_file.path
+                if os.path.exists(path_mrc_file):
+                    os.remove(path_mrc_file)
+
+
+@receiver(pre_save, sender=InteractFile)
+def updatemrcfile(sender, instance, **kwargs):
+    try:
+        old_interact = sender.objects.get(id=instance.id)
+    except sender.DoesNotExist:
+        old_interact = None
+    if instance.interact_file:
+        if old_interact:
+            if old_interact.interact_file:
+                path_interact_file = old_interact.interact_file.path
+                if os.path.exists(path_interact_file):
+                    os.remove(path_interact_file)