370 lines
15 KiB
Python
370 lines
15 KiB
Python
from django.core.exceptions import FieldDoesNotExist
|
|
from django.db.models.fields import NOT_PROVIDED
|
|
from django.utils.functional import cached_property
|
|
|
|
from .base import Operation
|
|
from .utils import is_referenced_by_foreign_key
|
|
|
|
|
|
class FieldOperation(Operation):
|
|
def __init__(self, model_name, name):
|
|
self.model_name = model_name
|
|
self.name = name
|
|
|
|
@cached_property
|
|
def model_name_lower(self):
|
|
return self.model_name.lower()
|
|
|
|
@cached_property
|
|
def name_lower(self):
|
|
return self.name.lower()
|
|
|
|
def is_same_model_operation(self, operation):
|
|
return self.model_name_lower == operation.model_name_lower
|
|
|
|
def is_same_field_operation(self, operation):
|
|
return self.is_same_model_operation(operation) and self.name_lower == operation.name_lower
|
|
|
|
def references_model(self, name, app_label=None):
|
|
return name.lower() == self.model_name_lower
|
|
|
|
def references_field(self, model_name, name, app_label=None):
|
|
return self.references_model(model_name) and name.lower() == self.name_lower
|
|
|
|
def reduce(self, operation, in_between, app_label=None):
|
|
return (
|
|
super().reduce(operation, in_between, app_label=app_label) or
|
|
not operation.references_field(self.model_name, self.name, app_label)
|
|
)
|
|
|
|
|
|
class AddField(FieldOperation):
|
|
"""Add a field to a model."""
|
|
|
|
def __init__(self, model_name, name, field, preserve_default=True):
|
|
self.field = field
|
|
self.preserve_default = preserve_default
|
|
super().__init__(model_name, name)
|
|
|
|
def deconstruct(self):
|
|
kwargs = {
|
|
'model_name': self.model_name,
|
|
'name': self.name,
|
|
'field': self.field,
|
|
}
|
|
if self.preserve_default is not True:
|
|
kwargs['preserve_default'] = self.preserve_default
|
|
return (
|
|
self.__class__.__name__,
|
|
[],
|
|
kwargs
|
|
)
|
|
|
|
def state_forwards(self, app_label, state):
|
|
# If preserve default is off, don't use the default for future state
|
|
if not self.preserve_default:
|
|
field = self.field.clone()
|
|
field.default = NOT_PROVIDED
|
|
else:
|
|
field = self.field
|
|
state.models[app_label, self.model_name_lower].fields.append((self.name, field))
|
|
# Delay rendering of relationships if it's not a relational field
|
|
delay = not field.is_relation
|
|
state.reload_model(app_label, self.model_name_lower, delay=delay)
|
|
|
|
def database_forwards(self, app_label, schema_editor, from_state, to_state):
|
|
to_model = to_state.apps.get_model(app_label, self.model_name)
|
|
if self.allow_migrate_model(schema_editor.connection.alias, to_model):
|
|
from_model = from_state.apps.get_model(app_label, self.model_name)
|
|
field = to_model._meta.get_field(self.name)
|
|
if not self.preserve_default:
|
|
field.default = self.field.default
|
|
schema_editor.add_field(
|
|
from_model,
|
|
field,
|
|
)
|
|
if not self.preserve_default:
|
|
field.default = NOT_PROVIDED
|
|
|
|
def database_backwards(self, app_label, schema_editor, from_state, to_state):
|
|
from_model = from_state.apps.get_model(app_label, self.model_name)
|
|
if self.allow_migrate_model(schema_editor.connection.alias, from_model):
|
|
schema_editor.remove_field(from_model, from_model._meta.get_field(self.name))
|
|
|
|
def describe(self):
|
|
return "Add field %s to %s" % (self.name, self.model_name)
|
|
|
|
def reduce(self, operation, in_between, app_label=None):
|
|
if isinstance(operation, FieldOperation) and self.is_same_field_operation(operation):
|
|
if isinstance(operation, AlterField):
|
|
return [
|
|
AddField(
|
|
model_name=self.model_name,
|
|
name=operation.name,
|
|
field=operation.field,
|
|
),
|
|
]
|
|
elif isinstance(operation, RemoveField):
|
|
return []
|
|
elif isinstance(operation, RenameField):
|
|
return [
|
|
AddField(
|
|
model_name=self.model_name,
|
|
name=operation.new_name,
|
|
field=self.field,
|
|
),
|
|
]
|
|
return super().reduce(operation, in_between, app_label=app_label)
|
|
|
|
|
|
class RemoveField(FieldOperation):
|
|
"""Remove a field from a model."""
|
|
|
|
def deconstruct(self):
|
|
kwargs = {
|
|
'model_name': self.model_name,
|
|
'name': self.name,
|
|
}
|
|
return (
|
|
self.__class__.__name__,
|
|
[],
|
|
kwargs
|
|
)
|
|
|
|
def state_forwards(self, app_label, state):
|
|
new_fields = []
|
|
old_field = None
|
|
for name, instance in state.models[app_label, self.model_name_lower].fields:
|
|
if name != self.name:
|
|
new_fields.append((name, instance))
|
|
else:
|
|
old_field = instance
|
|
state.models[app_label, self.model_name_lower].fields = new_fields
|
|
# Delay rendering of relationships if it's not a relational field
|
|
delay = not old_field.is_relation
|
|
state.reload_model(app_label, self.model_name_lower, delay=delay)
|
|
|
|
def database_forwards(self, app_label, schema_editor, from_state, to_state):
|
|
from_model = from_state.apps.get_model(app_label, self.model_name)
|
|
if self.allow_migrate_model(schema_editor.connection.alias, from_model):
|
|
schema_editor.remove_field(from_model, from_model._meta.get_field(self.name))
|
|
|
|
def database_backwards(self, app_label, schema_editor, from_state, to_state):
|
|
to_model = to_state.apps.get_model(app_label, self.model_name)
|
|
if self.allow_migrate_model(schema_editor.connection.alias, to_model):
|
|
from_model = from_state.apps.get_model(app_label, self.model_name)
|
|
schema_editor.add_field(from_model, to_model._meta.get_field(self.name))
|
|
|
|
def describe(self):
|
|
return "Remove field %s from %s" % (self.name, self.model_name)
|
|
|
|
|
|
class AlterField(FieldOperation):
|
|
"""
|
|
Alter a field's database column (e.g. null, max_length) to the provided
|
|
new field.
|
|
"""
|
|
|
|
def __init__(self, model_name, name, field, preserve_default=True):
|
|
self.field = field
|
|
self.preserve_default = preserve_default
|
|
super().__init__(model_name, name)
|
|
|
|
def deconstruct(self):
|
|
kwargs = {
|
|
'model_name': self.model_name,
|
|
'name': self.name,
|
|
'field': self.field,
|
|
}
|
|
if self.preserve_default is not True:
|
|
kwargs['preserve_default'] = self.preserve_default
|
|
return (
|
|
self.__class__.__name__,
|
|
[],
|
|
kwargs
|
|
)
|
|
|
|
def state_forwards(self, app_label, state):
|
|
if not self.preserve_default:
|
|
field = self.field.clone()
|
|
field.default = NOT_PROVIDED
|
|
else:
|
|
field = self.field
|
|
state.models[app_label, self.model_name_lower].fields = [
|
|
(n, field if n == self.name else f)
|
|
for n, f in
|
|
state.models[app_label, self.model_name_lower].fields
|
|
]
|
|
# TODO: investigate if old relational fields must be reloaded or if it's
|
|
# sufficient if the new field is (#27737).
|
|
# Delay rendering of relationships if it's not a relational field and
|
|
# not referenced by a foreign key.
|
|
delay = (
|
|
not field.is_relation and
|
|
not is_referenced_by_foreign_key(state, self.model_name_lower, self.field, self.name)
|
|
)
|
|
state.reload_model(app_label, self.model_name_lower, delay=delay)
|
|
|
|
def database_forwards(self, app_label, schema_editor, from_state, to_state):
|
|
to_model = to_state.apps.get_model(app_label, self.model_name)
|
|
if self.allow_migrate_model(schema_editor.connection.alias, to_model):
|
|
from_model = from_state.apps.get_model(app_label, self.model_name)
|
|
from_field = from_model._meta.get_field(self.name)
|
|
to_field = to_model._meta.get_field(self.name)
|
|
if not self.preserve_default:
|
|
to_field.default = self.field.default
|
|
schema_editor.alter_field(from_model, from_field, to_field)
|
|
if not self.preserve_default:
|
|
to_field.default = NOT_PROVIDED
|
|
|
|
def database_backwards(self, app_label, schema_editor, from_state, to_state):
|
|
self.database_forwards(app_label, schema_editor, from_state, to_state)
|
|
|
|
def describe(self):
|
|
return "Alter field %s on %s" % (self.name, self.model_name)
|
|
|
|
def reduce(self, operation, in_between, app_label=None):
|
|
if isinstance(operation, RemoveField) and self.is_same_field_operation(operation):
|
|
return [operation]
|
|
elif isinstance(operation, RenameField) and self.is_same_field_operation(operation):
|
|
return [
|
|
operation,
|
|
AlterField(
|
|
model_name=self.model_name,
|
|
name=operation.new_name,
|
|
field=self.field,
|
|
),
|
|
]
|
|
return super().reduce(operation, in_between, app_label=app_label)
|
|
|
|
|
|
class RenameField(FieldOperation):
|
|
"""Rename a field on the model. Might affect db_column too."""
|
|
|
|
def __init__(self, model_name, old_name, new_name):
|
|
self.old_name = old_name
|
|
self.new_name = new_name
|
|
super().__init__(model_name, old_name)
|
|
|
|
@cached_property
|
|
def old_name_lower(self):
|
|
return self.old_name.lower()
|
|
|
|
@cached_property
|
|
def new_name_lower(self):
|
|
return self.new_name.lower()
|
|
|
|
def deconstruct(self):
|
|
kwargs = {
|
|
'model_name': self.model_name,
|
|
'old_name': self.old_name,
|
|
'new_name': self.new_name,
|
|
}
|
|
return (
|
|
self.__class__.__name__,
|
|
[],
|
|
kwargs
|
|
)
|
|
|
|
def state_forwards(self, app_label, state):
|
|
model_state = state.models[app_label, self.model_name_lower]
|
|
# Rename the field
|
|
fields = model_state.fields
|
|
found = False
|
|
delay = True
|
|
for index, (name, field) in enumerate(fields):
|
|
if not found and name == self.old_name:
|
|
fields[index] = (self.new_name, field)
|
|
found = True
|
|
# Fix from_fields to refer to the new field.
|
|
from_fields = getattr(field, 'from_fields', None)
|
|
if from_fields:
|
|
field.from_fields = tuple([
|
|
self.new_name if from_field_name == self.old_name else from_field_name
|
|
for from_field_name in from_fields
|
|
])
|
|
# Delay rendering of relationships if it's not a relational
|
|
# field and not referenced by a foreign key.
|
|
delay = delay and (
|
|
not field.is_relation and
|
|
not is_referenced_by_foreign_key(state, self.model_name_lower, field, self.name)
|
|
)
|
|
if not found:
|
|
raise FieldDoesNotExist(
|
|
"%s.%s has no field named '%s'" % (app_label, self.model_name, self.old_name)
|
|
)
|
|
# Fix index/unique_together to refer to the new field
|
|
options = model_state.options
|
|
for option in ('index_together', 'unique_together'):
|
|
if option in options:
|
|
options[option] = [
|
|
[self.new_name if n == self.old_name else n for n in together]
|
|
for together in options[option]
|
|
]
|
|
# Fix to_fields to refer to the new field.
|
|
model_tuple = app_label, self.model_name_lower
|
|
for (model_app_label, model_name), model_state in state.models.items():
|
|
for index, (name, field) in enumerate(model_state.fields):
|
|
remote_field = field.remote_field
|
|
if remote_field:
|
|
remote_model_tuple = self._get_model_tuple(
|
|
remote_field.model, model_app_label, model_name
|
|
)
|
|
if remote_model_tuple == model_tuple:
|
|
if getattr(remote_field, 'field_name', None) == self.old_name:
|
|
remote_field.field_name = self.new_name
|
|
to_fields = getattr(field, 'to_fields', None)
|
|
if to_fields:
|
|
field.to_fields = tuple([
|
|
self.new_name if to_field_name == self.old_name else to_field_name
|
|
for to_field_name in to_fields
|
|
])
|
|
state.reload_model(app_label, self.model_name_lower, delay=delay)
|
|
|
|
def database_forwards(self, app_label, schema_editor, from_state, to_state):
|
|
to_model = to_state.apps.get_model(app_label, self.model_name)
|
|
if self.allow_migrate_model(schema_editor.connection.alias, to_model):
|
|
from_model = from_state.apps.get_model(app_label, self.model_name)
|
|
schema_editor.alter_field(
|
|
from_model,
|
|
from_model._meta.get_field(self.old_name),
|
|
to_model._meta.get_field(self.new_name),
|
|
)
|
|
|
|
def database_backwards(self, app_label, schema_editor, from_state, to_state):
|
|
to_model = to_state.apps.get_model(app_label, self.model_name)
|
|
if self.allow_migrate_model(schema_editor.connection.alias, to_model):
|
|
from_model = from_state.apps.get_model(app_label, self.model_name)
|
|
schema_editor.alter_field(
|
|
from_model,
|
|
from_model._meta.get_field(self.new_name),
|
|
to_model._meta.get_field(self.old_name),
|
|
)
|
|
|
|
def describe(self):
|
|
return "Rename field %s on %s to %s" % (self.old_name, self.model_name, self.new_name)
|
|
|
|
def references_field(self, model_name, name, app_label=None):
|
|
return self.references_model(model_name) and (
|
|
name.lower() == self.old_name_lower or
|
|
name.lower() == self.new_name_lower
|
|
)
|
|
|
|
def reduce(self, operation, in_between, app_label=None):
|
|
if (isinstance(operation, RenameField) and
|
|
self.is_same_model_operation(operation) and
|
|
self.new_name_lower == operation.old_name_lower):
|
|
return [
|
|
RenameField(
|
|
self.model_name,
|
|
self.old_name,
|
|
operation.new_name,
|
|
),
|
|
]
|
|
# Skip `FieldOperation.reduce` as we want to run `references_field`
|
|
# against self.new_name.
|
|
return (
|
|
super(FieldOperation, self).reduce(operation, in_between, app_label=app_label) or
|
|
not operation.references_field(self.model_name, self.new_name, app_label)
|
|
)
|