TMSS-573: a dataproduct should have a unique path

SAS/TMSS/backend/src/tmss/tmssapp/models/scheduling.py

@@ -9,7 +9,7 @@ logger = logging.getLogger(__name__)
 from datetime import datetime, timedelta
 
 from django.db.models import Model, ForeignKey, OneToOneField, CharField, DateTimeField, BooleanField, IntegerField, BigIntegerField, \
-    ManyToManyField, CASCADE, SET_NULL, PROTECT, QuerySet, BigAutoField
+    ManyToManyField, CASCADE, SET_NULL, PROTECT, QuerySet, BigAutoField, UniqueConstraint
 from django.contrib.postgres.fields import ArrayField, JSONField
 from django.contrib.auth.models import User
 from .specification import AbstractChoice, BasicCommon, Template, NamedCommon, annotate_validate_add_defaults_to_doc_using_template
@@ -375,6 +375,9 @@ class Dataproduct(BasicCommon):
     sap = ForeignKey('SAP', on_delete=PROTECT, null=True, related_name="dataproducts", help_text='SAP this dataproduct was generated out of (NULLable).')
     global_identifier = OneToOneField('SIPidentifier', editable=False, null=False, on_delete=PROTECT, help_text='The global unique identifier for LTA SIP.')
 
+    class Meta:
+        constraints = [UniqueConstraint(fields=['directory', 'filename'], name='%(class)s_unique_path')]
+
     def save(self, force_insert=False, force_update=False, using=None, update_fields=None):
         annotate_validate_add_defaults_to_doc_using_template(self, 'specifications_doc', 'specifications_template')
         annotate_validate_add_defaults_to_doc_using_template(self, 'feedback_doc', 'feedback_template')