def write_migration_files(self, changes):
"""
Take a changes dict and write them out as migration files.
"""
directory_created = {}
for app_label, app_migrations in changes.items():
if self.verbosity >= 1:
self.log(
self.style.MIGRATE_HEADING("Migrations for '%s':" %
app_label))
for migration in app_migrations:
# Describe the migration
writer = MigrationWriter(migration, self.include_header)
if self.verbosity >= 1:
# Display a relative path if it's below the current working
# directory, or an absolute path otherwise.
try:
migration_string = os.path.relpath(writer.path)
except ValueError:
migration_string = writer.path
if migration_string.startswith(".."):
migration_string = writer.path
self.log(" %s\n" %
self.style.MIGRATE_LABEL(migration_string))
for operation in migration.operations:
self.log(" - %s" % operation.describe())
if self.scriptable:
self.stdout.write(migration_string)
if not self.dry_run:
# Write the migrations file to the disk.
migrations_directory = os.path.dirname(writer.path)
if not directory_created.get(app_label):
os.makedirs(migrations_directory, exist_ok=True)
init_path = os.path.join(migrations_directory,
"__init__.py")
if not os.path.isfile(init_path):
open(init_path, "w").close()
# We just do this once per app
directory_created[app_label] = True
migration_string = writer.as_string()
with open(writer.path, "w", encoding="utf-8") as fh:
fh.write(migration_string)
self.written_files.append(writer.path)
elif self.verbosity == 3:
# Alternatively, makemigrations --dry-run --verbosity 3
# will log the migrations rather than saving the file to
# the disk.
self.log(
self.style.MIGRATE_HEADING(
"Full migrations file '%s':" % writer.filename))
self.log(writer.as_string())
run_formatters(self.written_files)
class TemplateCommand(BaseCommand):
"""
Copy either a Django application layout template or a Django project
layout template into the specified directory.
:param style: A color style object (see django.core.management.color).
:param app_or_project: The string 'app' or 'project'.
:param name: The name of the application or project.
:param directory: The directory to which the template should be copied.
:param options: The additional variables passed to project or app templates
"""
requires_system_checks = []
# The supported URL schemes
url_schemes = ["http", "https", "ftp"]
# Rewrite the following suffixes when determining the target filename.
rewrite_template_suffixes = (
# Allow shipping invalid .py files without byte-compilation.
(".py-tpl", ".py"),
)
def add_arguments(self, parser):
parser.add_argument("name", help="Name of the application or project.")
parser.add_argument(
"directory", nargs="?", help="Optional destination directory"
)
parser.add_argument(
"--template", help="The path or URL to load the template from."
)
parser.add_argument(
"--extension",
"-e",
dest="extensions",
action="append",
default=["py"],
help='The file extension(s) to render (default: "py"). '
"Separate multiple extensions with commas, or use "
"-e multiple times.",
)
parser.add_argument(
"--name",
"-n",
dest="files",
action="append",
default=[],
help="The file name(s) to render. Separate multiple file names "
"with commas, or use -n multiple times.",
)
parser.add_argument(
"--exclude",
"-x",
action="append",
default=argparse.SUPPRESS,
nargs="?",
const="",
help=(
"The directory name(s) to exclude, in addition to .git and "
"__pycache__. Can be used multiple times."
),
)
def handle(self, app_or_project, name, target=None, **options):
self.written_files = []
self.app_or_project = app_or_project
self.a_or_an = "an" if app_or_project == "app" else "a"
self.paths_to_remove = []
self.verbosity = options["verbosity"]
self.validate_name(name)
# if some directory is given, make sure it's nicely expanded
if target is None:
top_dir = os.path.join(os.getcwd(), name)
try:
os.makedirs(top_dir)
except FileExistsError:
raise CommandError("'%s' already exists" % top_dir)
except OSError as e:
raise CommandError(e)
else:
top_dir = os.path.abspath(os.path.expanduser(target))
if app_or_project == "app":
self.validate_name(os.path.basename(top_dir), "directory")
if not os.path.exists(top_dir):
raise CommandError(
"Destination directory '%s' does not "
"exist, please create it first." % top_dir
)
extensions = tuple(handle_extensions(options["extensions"]))
extra_files = []
excluded_directories = [".git", "__pycache__"]
for file in options["files"]:
extra_files.extend(map(lambda x: x.strip(), file.split(",")))
if exclude := options.get("exclude"):
for directory in exclude:
excluded_directories.append(directory.strip())
if self.verbosity >= 2:
self.stdout.write(
"Rendering %s template files with extensions: %s"
% (app_or_project, ", ".join(extensions))
)
self.stdout.write(
"Rendering %s template files with filenames: %s"
% (app_or_project, ", ".join(extra_files))
)
base_name = "%s_name" % app_or_project
base_subdir = "%s_template" % app_or_project
base_directory = "%s_directory" % app_or_project
camel_case_name = "camel_case_%s_name" % app_or_project
camel_case_value = "".join(x for x in name.title() if x != "_")
context = Context(
{
**options,
base_name: name,
base_directory: top_dir,
camel_case_name: camel_case_value,
"docs_version": get_docs_version(),
"django_version": django.__version__,
},
autoescape=False,
)
# Setup a stub settings environment for template rendering
if not settings.configured:
settings.configure()
django.setup()
template_dir = self.handle_template(options["template"], base_subdir)
prefix_length = len(template_dir) + 1
for root, dirs, files in os.walk(template_dir):
path_rest = root[prefix_length:]
relative_dir = path_rest.replace(base_name, name)
if relative_dir:
target_dir = os.path.join(top_dir, relative_dir)
os.makedirs(target_dir, exist_ok=True)
for dirname in dirs[:]:
if "exclude" not in options:
if dirname.startswith(".") or dirname == "__pycache__":
dirs.remove(dirname)
elif dirname in excluded_directories:
dirs.remove(dirname)
for filename in files:
if filename.endswith((".pyo", ".pyc", ".py.class")):
# Ignore some files as they cause various breakages.
continue
old_path = os.path.join(root, filename)
new_path = os.path.join(
top_dir, relative_dir, filename.replace(base_name, name)
)
for old_suffix, new_suffix in self.rewrite_template_suffixes:
if new_path.endswith(old_suffix):
new_path = new_path[: -len(old_suffix)] + new_suffix
break # Only rewrite once
if os.path.exists(new_path):
raise CommandError(
"%s already exists. Overlaying %s %s into an existing "
"directory won't replace conflicting files."
% (
new_path,
self.a_or_an,
app_or_project,
)
)
# Only render the Python files, as we don't want to
# accidentally render Django templates files
if new_path.endswith(extensions) or filename in extra_files:
with open(old_path, encoding="utf-8") as template_file:
content = template_file.read()
template = Engine().from_string(content)
content = template.render(context)
with open(new_path, "w", encoding="utf-8") as new_file:
new_file.write(content)
else:
shutil.copyfile(old_path, new_path)
self.written_files.append(new_path)
if self.verbosity >= 2:
self.stdout.write("Creating %s" % new_path)
try:
self.apply_umask(old_path, new_path)
self.make_writeable(new_path)
except OSError:
self.stderr.write(
"Notice: Couldn't set permission bits on %s. You're "
"probably using an uncommon filesystem setup. No "
"problem." % new_path,
self.style.NOTICE,
)
if self.paths_to_remove:
if self.verbosity >= 2:
self.stdout.write("Cleaning up temporary files.")
for path_to_remove in self.paths_to_remove:
if os.path.isfile(path_to_remove):
os.remove(path_to_remove)
else:
shutil.rmtree(path_to_remove)
run_formatters(self.written_files)
def handle_merge(self, loader, conflicts):
"""
Handles merging together conflicted migrations interactively,
if it's safe; otherwise, advises on how to fix it.
"""
if self.interactive:
questioner = InteractiveMigrationQuestioner(prompt_output=self.log_output)
else:
questioner = MigrationQuestioner(defaults={"ask_merge": True})
for app_label, migration_names in conflicts.items():
# Grab out the migrations in question, and work out their
# common ancestor.
merge_migrations = []
for migration_name in migration_names:
migration = loader.get_migration(app_label, migration_name)
migration.ancestry = [
mig
for mig in loader.graph.forwards_plan((app_label, migration_name))
if mig[0] == migration.app_label
]
merge_migrations.append(migration)
def all_items_equal(seq):
return all(item == seq[0] for item in seq[1:])
merge_migrations_generations = zip(*(m.ancestry for m in merge_migrations))
common_ancestor_count = sum(
1
for common_ancestor_generation in takewhile(
all_items_equal, merge_migrations_generations
)
)
if not common_ancestor_count:
raise ValueError(
"Could not find common ancestor of %s" % migration_names
)
# Now work out the operations along each divergent branch
for migration in merge_migrations:
migration.branch = migration.ancestry[common_ancestor_count:]
migrations_ops = (
loader.get_migration(node_app, node_name).operations
for node_app, node_name in migration.branch
)
migration.merged_operations = sum(migrations_ops, [])
# In future, this could use some of the Optimizer code
# (can_optimize_through) to automatically see if they're
# mergeable. For now, we always just prompt the user.
if self.verbosity > 0:
self.log(self.style.MIGRATE_HEADING("Merging %s" % app_label))
for migration in merge_migrations:
self.log(self.style.MIGRATE_LABEL(" Branch %s" % migration.name))
for operation in migration.merged_operations:
self.log(" - %s" % operation.describe())
if questioner.ask_merge(app_label):
# If they still want to merge it, then write out an empty
# file depending on the migrations needing merging.
numbers = [
MigrationAutodetector.parse_number(migration.name)
for migration in merge_migrations
]
try:
biggest_number = max(x for x in numbers if x is not None)
except ValueError:
biggest_number = 1
subclass = type(
"Migration",
(Migration,),
{
"dependencies": [
(app_label, migration.name)
for migration in merge_migrations
],
},
)
parts = ["%04i" % (biggest_number + 1)]
if self.migration_name:
parts.append(self.migration_name)
else:
parts.append("merge")
leaf_names = "_".join(
sorted(migration.name for migration in merge_migrations)
)
if len(leaf_names) > 47:
parts.append(get_migration_name_timestamp())
else:
parts.append(leaf_names)
migration_name = "_".join(parts)
new_migration = subclass(migration_name, app_label)
writer = MigrationWriter(new_migration, self.include_header)
if not self.dry_run:
# Write the merge migrations file to the disk
with open(writer.path, "w", encoding="utf-8") as fh:
fh.write(writer.as_string())
run_formatters([writer.path])
if self.verbosity > 0:
self.log("\nCreated new merge migration %s" % writer.path)
if self.scriptable:
self.stdout.write(writer.path)
elif self.verbosity == 3:
# Alternatively, makemigrations --merge --dry-run --verbosity 3
# will log the merge migrations rather than saving the file
# to the disk.
self.log(
self.style.MIGRATE_HEADING(
"Full merge migrations file '%s':" % writer.filename
)
)
self.log(writer.as_string())
def write_migration_files(self, changes, update_previous_migration_paths=None):
"""
Take a changes dict and write them out as migration files.
"""
directory_created = {}
for app_label, app_migrations in changes.items():
if self.verbosity >= 1:
self.log(self.style.MIGRATE_HEADING("Migrations for '%s':" % app_label))
for migration in app_migrations:
# Describe the migration
writer = MigrationWriter(migration, self.include_header)
if self.verbosity >= 1:
# Display a relative path if it's below the current working
# directory, or an absolute path otherwise.
migration_string = self.get_relative_path(writer.path)
self.log(" %s\n" % self.style.MIGRATE_LABEL(migration_string))
for operation in migration.operations:
self.log(" - %s" % operation.describe())
if self.scriptable:
self.stdout.write(migration_string)
if not self.dry_run:
# Write the migrations file to the disk.
migrations_directory = os.path.dirname(writer.path)
if not directory_created.get(app_label):
os.makedirs(migrations_directory, exist_ok=True)
init_path = os.path.join(migrations_directory, "__init__.py")
if not os.path.isfile(init_path):
open(init_path, "w").close()
# We just do this once per app
directory_created[app_label] = True
migration_string = writer.as_string()
with open(writer.path, "w", encoding="utf-8") as fh:
fh.write(migration_string)
self.written_files.append(writer.path)
if update_previous_migration_paths:
prev_path = update_previous_migration_paths[app_label]
rel_prev_path = self.get_relative_path(prev_path)
if writer.needs_manual_porting:
migration_path = self.get_relative_path(writer.path)
self.log(
self.style.WARNING(
f"Updated migration {migration_path} requires "
f"manual porting.\n"
f"Previous migration {rel_prev_path} was kept and "
f"must be deleted after porting functions manually."
)
)
else:
os.remove(prev_path)
self.log(f"Deleted {rel_prev_path}")
elif self.verbosity == 3:
# Alternatively, makemigrations --dry-run --verbosity 3
# will log the migrations rather than saving the file to
# the disk.
self.log(
self.style.MIGRATE_HEADING(
"Full migrations file '%s':" % writer.filename
)
)
self.log(writer.as_string())
run_formatters(self.written_files)
def handle(self, **options):
self.verbosity = options["verbosity"]
self.interactive = options["interactive"]
app_label = options["app_label"]
start_migration_name = options["start_migration_name"]
migration_name = options["migration_name"]
no_optimize = options["no_optimize"]
squashed_name = options["squashed_name"]
include_header = options["include_header"]
# Validate app_label.
try:
apps.get_app_config(app_label)
except LookupError as err:
raise CommandError(str(err))
# Load the current graph state, check the app and migration they asked
# for exists.
loader = MigrationLoader(connections[DEFAULT_DB_ALIAS])
if app_label not in loader.migrated_apps:
raise CommandError(
"App '%s' does not have migrations (so squashmigrations on "
"it makes no sense)" % app_label)
migration = self.find_migration(loader, app_label, migration_name)
# Work out the list of predecessor migrations
migrations_to_squash = [
loader.get_migration(al, mn)
for al, mn in loader.graph.forwards_plan((migration.app_label,
migration.name))
if al == migration.app_label
]
if start_migration_name:
start_migration = self.find_migration(loader, app_label,
start_migration_name)
start = loader.get_migration(start_migration.app_label,
start_migration.name)
try:
start_index = migrations_to_squash.index(start)
migrations_to_squash = migrations_to_squash[start_index:]
except ValueError:
raise CommandError(
"The migration '%s' cannot be found. Maybe it comes after "
"the migration '%s'?\n"
"Have a look at:\n"
" python manage.py showmigrations %s\n"
"to debug this issue." %
(start_migration, migration, app_label))
# Tell them what we're doing and optionally ask if we should proceed
if self.verbosity > 0 or self.interactive:
self.stdout.write(
self.style.MIGRATE_HEADING(
"Will squash the following migrations:"))
for migration in migrations_to_squash:
self.stdout.write(" - %s" % migration.name)
if self.interactive:
answer = None
while not answer or answer not in "yn":
answer = input("Do you wish to proceed? [yN] ")
if not answer:
answer = "n"
break
else:
answer = answer[0].lower()
if answer != "y":
return
# Load the operations from all those migrations and concat together,
# along with collecting external dependencies and detecting
# double-squashing
operations = []
dependencies = set()
# We need to take all dependencies from the first migration in the list
# as it may be 0002 depending on 0001
first_migration = True
for smigration in migrations_to_squash:
if smigration.replaces:
raise CommandError(
"You cannot squash squashed migrations! Please transition it to a "
"normal migration first: https://docs.djangoproject.com/en/%s/"
"topics/migrations/#squashing-migrations" %
get_docs_version())
operations.extend(smigration.operations)
for dependency in smigration.dependencies:
if isinstance(dependency, SwappableTuple):
if settings.AUTH_USER_MODEL == dependency.setting:
dependencies.add(("__setting__", "AUTH_USER_MODEL"))
else:
dependencies.add(dependency)
elif dependency[0] != smigration.app_label or first_migration:
dependencies.add(dependency)
first_migration = False
if no_optimize:
if self.verbosity > 0:
self.stdout.write(
self.style.MIGRATE_HEADING("(Skipping optimization.)"))
new_operations = operations
else:
if self.verbosity > 0:
self.stdout.write(self.style.MIGRATE_HEADING("Optimizing..."))
optimizer = MigrationOptimizer()
new_operations = optimizer.optimize(operations,
migration.app_label)
if self.verbosity > 0:
if len(new_operations) == len(operations):
self.stdout.write(" No optimizations possible.")
else:
self.stdout.write(
" Optimized from %s operations to %s operations." %
(len(operations), len(new_operations)))
# Work out the value of replaces (any squashed ones we're re-squashing)
# need to feed their replaces into ours
replaces = []
for migration in migrations_to_squash:
if migration.replaces:
replaces.extend(migration.replaces)
else:
replaces.append((migration.app_label, migration.name))
# Make a new migration with those operations
subclass = type(
"Migration",
(migrations.Migration, ),
{
"dependencies": dependencies,
"operations": new_operations,
"replaces": replaces,
},
)
if start_migration_name:
if squashed_name:
# Use the name from --squashed-name.
prefix, _ = start_migration.name.split("_", 1)
name = "%s_%s" % (prefix, squashed_name)
else:
# Generate a name.
name = "%s_squashed_%s" % (start_migration.name,
migration.name)
new_migration = subclass(name, app_label)
else:
name = "0001_%s" % (squashed_name
or "squashed_%s" % migration.name)
new_migration = subclass(name, app_label)
new_migration.initial = True
# Write out the new migration file
writer = MigrationWriter(new_migration, include_header)
if os.path.exists(writer.path):
raise CommandError(
f"Migration {new_migration.name} already exists. Use a different name."
)
with open(writer.path, "w", encoding="utf-8") as fh:
fh.write(writer.as_string())
run_formatters([writer.path])
if self.verbosity > 0:
self.stdout.write(
self.style.MIGRATE_HEADING(
"Created new squashed migration %s" % writer.path) + "\n"
" You should commit this migration but leave the old ones in place;\n"
" the new migration will be used for new installs. Once you are sure\n"
" all instances of the codebase have applied the migrations you "
"squashed,\n"
" you can delete them.")
if writer.needs_manual_porting:
self.stdout.write(
self.style.MIGRATE_HEADING("Manual porting required") +
"\n"
" Your migrations contained functions that must be manually "
"copied over,\n"
" as we could not safely copy their implementation.\n"
" See the comment at the top of the squashed migration for "
"details.")
if shutil.which("black"):
self.stdout.write(
self.style.WARNING(
"Squashed migration couldn't be formatted using the "
'"black" command. You can call it manually.'))
def handle(self, *args, **options):
verbosity = options["verbosity"]
app_label = options["app_label"]
migration_name = options["migration_name"]
check = options["check"]
# Validate app_label.
try:
apps.get_app_config(app_label)
except LookupError as err:
raise CommandError(str(err))
# Load the current graph state.
loader = MigrationLoader(None)
if app_label not in loader.migrated_apps:
raise CommandError(f"App '{app_label}' does not have migrations.")
# Find a migration.
try:
migration = loader.get_migration_by_prefix(app_label, migration_name)
except AmbiguityError:
raise CommandError(
f"More than one migration matches '{migration_name}' in app "
f"'{app_label}'. Please be more specific."
)
except KeyError:
raise CommandError(
f"Cannot find a migration matching '{migration_name}' from app "
f"'{app_label}'."
)
# Optimize the migration.
optimizer = MigrationOptimizer()
new_operations = optimizer.optimize(migration.operations, migration.app_label)
if len(migration.operations) == len(new_operations):
if verbosity > 0:
self.stdout.write("No optimizations possible.")
return
else:
if verbosity > 0:
self.stdout.write(
"Optimizing from %d operations to %d operations."
% (len(migration.operations), len(new_operations))
)
if check:
sys.exit(1)
# Set the new migration optimizations.
migration.operations = new_operations
# Write out the optimized migration file.
writer = MigrationWriter(migration)
migration_file_string = writer.as_string()
if writer.needs_manual_porting:
if migration.replaces:
raise CommandError(
"Migration will require manual porting but is already a squashed "
"migration.\nTransition to a normal migration first: "
"https://docs.djangoproject.com/en/%s/topics/migrations/"
"#squashing-migrations" % get_docs_version()
)
# Make a new migration with those operations.
subclass = type(
"Migration",
(migrations.Migration,),
{
"dependencies": migration.dependencies,
"operations": new_operations,
"replaces": [(migration.app_label, migration.name)],
},
)
optimized_migration_name = "%s_optimized" % migration.name
optimized_migration = subclass(optimized_migration_name, app_label)
writer = MigrationWriter(optimized_migration)
migration_file_string = writer.as_string()
if verbosity > 0:
self.stdout.write(
self.style.MIGRATE_HEADING("Manual porting required") + "\n"
" Your migrations contained functions that must be manually "
"copied over,\n"
" as we could not safely copy their implementation.\n"
" See the comment at the top of the optimized migration for "
"details."
)
if shutil.which("black"):
self.stdout.write(
self.style.WARNING(
"Optimized migration couldn't be formatted using the "
'"black" command. You can call it manually.'
)
)
with open(writer.path, "w", encoding="utf-8") as fh:
fh.write(migration_file_string)
run_formatters([writer.path])
if verbosity > 0:
self.stdout.write(
self.style.MIGRATE_HEADING(f"Optimized migration {writer.path}")
)