diff --git a/django/db/migrations/autodetector.py b/django/db/migrations/autodetector.py index 213516f908..a5aec671f8 100644 --- a/django/db/migrations/autodetector.py +++ b/django/db/migrations/autodetector.py @@ -1,4 +1,6 @@ import re +import sys +from django.utils import datetime_safe from django.utils.six.moves import input from django.db.migrations import operations from django.db.migrations.migration import Migration @@ -66,12 +68,16 @@ class MigrationAutodetector(object): old_field_names = set([x for x, y in old_model_state.fields]) new_field_names = set([x for x, y in new_model_state.fields]) for field_name in new_field_names - old_field_names: + field = [y for x, y in new_model_state.fields if x == field_name][0] + # You can't just add NOT NULL fields with no default + if not field.null and not field.has_default(): + field.default = self.questioner.ask_not_null_addition(field_name, model_name) self.add_to_migration( app_label, operations.AddField( model_name = model_name, name = field_name, - field = [y for x, y in new_model_state.fields if x == field_name][0], + field = field, ) ) # Old fields @@ -180,6 +186,10 @@ class MigrationAutodetector(object): return ops[0].name.lower() elif isinstance(ops[0], operations.DeleteModel): return "delete_%s" % ops[0].name.lower() + elif isinstance(ops[0], operations.AddField): + return "%s_%s" % (ops[0].model_name.lower(), ops[0].name.lower()) + elif isinstance(ops[0], operations.RemoveField): + return "remove_%s_%s" % (ops[0].model_name.lower(), ops[0].name.lower()) elif all(isinstance(o, operations.CreateModel) for o in ops): return "_".join(sorted(o.name.lower() for o in ops)) return "auto" @@ -209,6 +219,11 @@ class MigrationQuestioner(object): "Should we create an initial migration for the app?" return self.defaults.get("ask_initial", False) + def ask_not_null_addition(self, field_name, model_name): + "Adding a NOT NULL field to a model" + # None means quit + return None + class InteractiveMigrationQuestioner(MigrationQuestioner): @@ -221,7 +236,22 @@ class InteractiveMigrationQuestioner(MigrationQuestioner): result = input("Please answer yes or no: ") return result[0].lower() == "y" + def _choice_input(self, question, choices): + print question + for i, choice in enumerate(choices): + print " %s) %s" % (i + 1, choice) + result = input("Select an option: ") + while True: + try: + value = int(result) + if 0 < value <= len(choices): + return value + except ValueError: + pass + result = input("Please select a valid option: ") + def ask_initial(self, app_label): + "Should we create an initial migration for the app?" # Don't ask for django.contrib apps app = cache.get_app(app_label) if app.__name__.startswith("django.contrib"): @@ -231,3 +261,32 @@ class InteractiveMigrationQuestioner(MigrationQuestioner): return True # Now ask return self._boolean_input("Do you want to enable migrations for app '%s'?" % app_label) + + def ask_not_null_addition(self, field_name, model_name): + "Adding a NOT NULL field to a model" + choice = self._choice_input( + "You are trying to add a non-nullable field '%s' to %s without a default;\n" % (field_name, model_name) + + "this is not possible. Please select a fix:", + [ + "Provide a one-off default now (will be set on all existing rows)", + "Quit, and let me add a default in models.py", + ] + ) + if choice == 2: + sys.exit(3) + else: + print("Please enter the default value now, as valid Python") + print("The datetime module is available, so you can do e.g. datetime.date.today()") + while True: + code = input(">>> ") + if not code: + print("Please enter some code, or 'exit' (with no quotes) to exit.") + elif code == "exit": + sys.exit(1) + else: + try: + return eval(code, {}, {"datetime": datetime_safe}) + except (SyntaxError, NameError) as e: + print("Invalid input: %s" % e) + else: + break