[1.10.x] Fixed #27054 -- Fixed makemigrations crash with a read-only database.

Backport of 76ab8851181675a59425f9637bdbf3f2de95f6f1 from master

1 files changed, 7 insertions, 1 deletions

diff --git a/django/db/migrations/loader.py b/django/db/migrations/loader.py
index d459f2c524..e5a7f031f9 100644
--- a/django/db/migrations/loader.py
+++ b/django/db/migrations/loader.py
@@ -6,6 +6,7 @@ from importlib import import_module
 
 from django.apps import apps
 from django.conf import settings
+from django.db.migrations.exceptions import MigrationSchemaMissing
 from django.db.migrations.graph import MigrationGraph
 from django.db.migrations.recorder import MigrationRecorder
 from django.utils import six
@@ -273,7 +274,12 @@ class MigrationLoader(object):
         unapplied dependencies.
         """
         recorder = MigrationRecorder(connection)
-        applied = recorder.applied_migrations()
+        try:
+            applied = recorder.applied_migrations()
+        except MigrationSchemaMissing:
+            # Skip check if the django_migrations table is missing and can't be
+            # created.
+            return
         for migration in applied:
             # If the migration is unknown, skip it.
             if migration not in self.graph.nodes: