diff options
Diffstat (limited to 'django')
| -rw-r--r-- | django/core/management/commands/migrate.py | 43 |
1 files changed, 42 insertions, 1 deletions
diff --git a/django/core/management/commands/migrate.py b/django/core/management/commands/migrate.py index 1e407831b4..299edbe421 100644 --- a/django/core/management/commands/migrate.py +++ b/django/core/management/commands/migrate.py @@ -16,6 +16,7 @@ from django.db.migrations.executor import MigrationExecutor from django.db.migrations.loader import AmbiguityError from django.db.migrations.state import ModelState, ProjectState from django.utils.module_loading import module_has_submodule +from django.utils.text import Truncator class Command(BaseCommand): @@ -51,6 +52,10 @@ class Command(BaseCommand): 'flag. Django will only check for an existing table name.', ) parser.add_argument( + '--plan', action='store_true', + help='Shows a list of the migration actions that will be performed.', + ) + parser.add_argument( '--run-syncdb', action='store_true', help='Creates tables for apps without migrations.', ) @@ -134,8 +139,20 @@ class Command(BaseCommand): targets = executor.loader.graph.leaf_nodes() plan = executor.migration_plan(targets) - run_syncdb = options['run_syncdb'] and executor.loader.unmigrated_apps + if options['plan']: + self.stdout.write('Planned operations:', self.style.MIGRATE_LABEL) + if not plan: + self.stdout.write(' No planned migration operations.') + for migration, backwards in plan: + self.stdout.write(str(migration), self.style.MIGRATE_HEADING) + for operation in migration.operations: + message, is_error = self.describe_operation(operation, backwards) + style = self.style.WARNING if is_error else None + self.stdout.write(' ' + message, style) + return + + run_syncdb = options['run_syncdb'] and executor.loader.unmigrated_apps # Print some useful info if self.verbosity >= 1: self.stdout.write(self.style.MIGRATE_HEADING("Operations to perform:")) @@ -309,3 +326,27 @@ class Command(BaseCommand): # Deferred SQL is executed when exiting the editor's context. if self.verbosity >= 1: self.stdout.write(" Running deferred SQL...\n") + + @staticmethod + def describe_operation(operation, backwards): + """Return a string that describes a migration operation for --plan.""" + prefix = '' + if hasattr(operation, 'code'): + code = operation.reverse_code if backwards else operation.code + action = code.__doc__ if code else '' + elif hasattr(operation, 'sql'): + action = operation.reverse_sql if backwards else operation.sql + else: + action = '' + if backwards: + prefix = 'Undo ' + if action is None: + action = 'IRREVERSIBLE' + is_error = True + else: + action = action.replace('\n', '') + is_error = False + if action: + action = ' -> ' + action + truncated = Truncator(action) + return prefix + operation.describe() + truncated.chars(40), is_error |