dbt-selly/dbt-env/lib/python3.8/site-packages/dbt/dataclass_schema.py

170 lines
5.0 KiB
Python

from typing import (
Type, ClassVar, cast,
)
import re
from dataclasses import fields
from enum import Enum
from datetime import datetime
from dateutil.parser import parse
from hologram import JsonSchemaMixin, FieldEncoder, ValidationError
# type: ignore
from mashumaro import DataClassDictMixin
from mashumaro.config import (
TO_DICT_ADD_OMIT_NONE_FLAG, BaseConfig as MashBaseConfig
)
from mashumaro.types import SerializableType, SerializationStrategy
class DateTimeSerialization(SerializationStrategy):
def serialize(self, value):
out = value.isoformat()
# Assume UTC if timezone is missing
if value.tzinfo is None:
out = out + "Z"
return out
def deserialize(self, value):
return (
value if isinstance(value, datetime) else parse(cast(str, value))
)
# This class pulls in both JsonSchemaMixin from Hologram and
# DataClassDictMixin from our fork of Mashumaro. The 'to_dict'
# and 'from_dict' methods come from Mashumaro. Building
# jsonschemas for every class and the 'validate' method
# come from Hologram.
class dbtClassMixin(DataClassDictMixin, JsonSchemaMixin):
"""Mixin which adds methods to generate a JSON schema and
convert to and from JSON encodable dicts with validation
against the schema
"""
class Config(MashBaseConfig):
code_generation_options = [
TO_DICT_ADD_OMIT_NONE_FLAG,
]
serialization_strategy = {
datetime: DateTimeSerialization(),
}
_hyphenated: ClassVar[bool] = False
ADDITIONAL_PROPERTIES: ClassVar[bool] = False
# This is called by the mashumaro to_dict in order to handle
# nested classes.
# Munges the dict that's returned.
def __post_serialize__(self, dct):
if self._hyphenated:
new_dict = {}
for key in dct:
if '_' in key:
new_key = key.replace('_', '-')
new_dict[new_key] = dct[key]
else:
new_dict[key] = dct[key]
dct = new_dict
return dct
# This is called by the mashumaro _from_dict method, before
# performing the conversion to a dict
@classmethod
def __pre_deserialize__(cls, data):
# `data` might not be a dict, e.g. for `query_comment`, which accepts
# a dict or a string; only snake-case for dict values.
if cls._hyphenated and isinstance(data, dict):
new_dict = {}
for key in data:
if '-' in key:
new_key = key.replace('-', '_')
new_dict[new_key] = data[key]
else:
new_dict[key] = data[key]
data = new_dict
return data
# This is used in the hologram._encode_field method, which calls
# a 'to_dict' method which does not have the same parameters in
# hologram and in mashumaro.
def _local_to_dict(self, **kwargs):
args = {}
if 'omit_none' in kwargs:
args['omit_none'] = kwargs['omit_none']
return self.to_dict(**args)
class ValidatedStringMixin(str, SerializableType):
ValidationRegex = ''
@classmethod
def _deserialize(cls, value: str) -> 'ValidatedStringMixin':
cls.validate(value)
return ValidatedStringMixin(value)
def _serialize(self) -> str:
return str(self)
@classmethod
def validate(cls, value):
res = re.match(cls.ValidationRegex, value)
if res is None:
raise ValidationError(f"Invalid value: {value}") # TODO
# These classes must be in this order or it doesn't work
class StrEnum(str, SerializableType, Enum):
def __str__(self):
return self.value
# https://docs.python.org/3.6/library/enum.html#using-automatic-values
def _generate_next_value_(name, *_):
return name
def _serialize(self) -> str:
return self.value
@classmethod
def _deserialize(cls, value: str):
return cls(value)
class HyphenatedDbtClassMixin(dbtClassMixin):
# used by from_dict/to_dict
_hyphenated: ClassVar[bool] = True
# used by jsonschema validation, _get_fields
@classmethod
def field_mapping(cls):
result = {}
for field in fields(cls):
skip = field.metadata.get("preserve_underscore")
if skip:
continue
if "_" in field.name:
result[field.name] = field.name.replace("_", "-")
return result
class ExtensibleDbtClassMixin(dbtClassMixin):
ADDITIONAL_PROPERTIES = True
# This is used by Hologram in jsonschema validation
def register_pattern(base_type: Type, pattern: str) -> None:
"""base_type should be a typing.NewType that should always have the given
regex pattern. That means that its underlying type ('__supertype__') had
better be a str!
"""
class PatternEncoder(FieldEncoder):
@property
def json_schema(self):
return {"type": "string", "pattern": pattern}
dbtClassMixin.register_field_encoders({base_type: PatternEncoder()})