Files
ormar/ormar/models/mixins/alias_mixin.py
2020-12-31 11:52:05 +01:00

73 lines
2.7 KiB
Python

from typing import Dict, TYPE_CHECKING
class AliasMixin:
"""
Used to translate field names into database column names.
"""
if TYPE_CHECKING: # pragma: no cover
from ormar import ModelMeta
Meta: ModelMeta
@classmethod
def get_column_alias(cls, field_name: str) -> str:
"""
Returns db alias (column name in db) for given ormar field.
For fields without alias field name is returned.
:param field_name: name of the field to get alias from
:type field_name: str
:return: alias (db name) if set, otherwise passed name
:rtype: str
"""
field = cls.Meta.model_fields.get(field_name)
return field.get_alias() if field is not None else field_name
@classmethod
def get_column_name_from_alias(cls, alias: str) -> str:
"""
Returns ormar field name for given db alias (column name in db).
If field do not have alias it's returned as is.
:param alias:
:type alias: str
:return: field name if set, otherwise passed alias (db name)
:rtype: str
"""
for field_name, field in cls.Meta.model_fields.items():
if field.get_alias() == alias:
return field_name
return alias # if not found it's not an alias but actual name
@classmethod
def translate_columns_to_aliases(cls, new_kwargs: Dict) -> Dict:
"""
Translates dictionary of model fields changing field names into aliases.
If field has no alias the field name remains intact.
Only fields present in the dictionary are translated.
:param new_kwargs: dict with fields names and their values
:type new_kwargs: Dict
:return: dict with aliases and their values
:rtype: Dict
"""
for field_name, field in cls.Meta.model_fields.items():
if field_name in new_kwargs:
new_kwargs[field.get_alias()] = new_kwargs.pop(field_name)
return new_kwargs
@classmethod
def translate_aliases_to_columns(cls, new_kwargs: Dict) -> Dict:
"""
Translates dictionary of model fields changing aliases into field names.
If field has no alias the alias is already a field name.
Only fields present in the dictionary are translated.
:param new_kwargs: dict with aliases and their values
:type new_kwargs: Dict
:return: dict with fields names and their values
:rtype: Dict
"""
for field_name, field in cls.Meta.model_fields.items():
if field.alias and field.alias in new_kwargs:
new_kwargs[field_name] = new_kwargs.pop(field.alias)
return new_kwargs