dbt-selly/dbt-env/lib/python3.8/site-packages/dbt/adapters/base/relation.py

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2022-03-22 15:13:27 +00:00
from collections.abc import Hashable
from dataclasses import dataclass
from typing import (
Optional, TypeVar, Any, Type, Dict, Union, Iterator, Tuple, Set
)
from dbt.contracts.graph.compiled import CompiledNode
from dbt.contracts.graph.parsed import ParsedSourceDefinition, ParsedNode
from dbt.contracts.relation import (
RelationType, ComponentName, HasQuoting, FakeAPIObject, Policy, Path
)
from dbt.exceptions import InternalException
from dbt.node_types import NodeType
from dbt.utils import filter_null_values, deep_merge, classproperty
import dbt.exceptions
Self = TypeVar('Self', bound='BaseRelation')
@dataclass(frozen=True, eq=False, repr=False)
class BaseRelation(FakeAPIObject, Hashable):
path: Path
type: Optional[RelationType] = None
quote_character: str = '"'
include_policy: Policy = Policy()
quote_policy: Policy = Policy()
dbt_created: bool = False
def _is_exactish_match(self, field: ComponentName, value: str) -> bool:
if self.dbt_created and self.quote_policy.get_part(field) is False:
return self.path.get_lowered_part(field) == value.lower()
else:
return self.path.get_part(field) == value
@classmethod
def _get_field_named(cls, field_name):
for field, _ in cls._get_fields():
if field.name == field_name:
return field
# this should be unreachable
raise ValueError(f'BaseRelation has no {field_name} field!')
def __eq__(self, other):
if not isinstance(other, self.__class__):
return False
return self.to_dict(omit_none=True) == other.to_dict(omit_none=True)
@classmethod
def get_default_quote_policy(cls) -> Policy:
return cls._get_field_named('quote_policy').default
@classmethod
def get_default_include_policy(cls) -> Policy:
return cls._get_field_named('include_policy').default
def get(self, key, default=None):
"""Override `.get` to return a metadata object so we don't break
dbt_utils.
"""
if key == 'metadata':
return {
'type': self.__class__.__name__
}
return super().get(key, default)
def matches(
self,
database: Optional[str] = None,
schema: Optional[str] = None,
identifier: Optional[str] = None,
) -> bool:
search = filter_null_values({
ComponentName.Database: database,
ComponentName.Schema: schema,
ComponentName.Identifier: identifier
})
if not search:
# nothing was passed in
raise dbt.exceptions.RuntimeException(
"Tried to match relation, but no search path was passed!")
exact_match = True
approximate_match = True
for k, v in search.items():
if not self._is_exactish_match(k, v):
exact_match = False
if self.path.get_lowered_part(k) != v.lower():
approximate_match = False
if approximate_match and not exact_match:
target = self.create(
database=database, schema=schema, identifier=identifier
)
dbt.exceptions.approximate_relation_match(target, self)
return exact_match
def replace_path(self, **kwargs):
return self.replace(path=self.path.replace(**kwargs))
def quote(
self: Self,
database: Optional[bool] = None,
schema: Optional[bool] = None,
identifier: Optional[bool] = None,
) -> Self:
policy = filter_null_values({
ComponentName.Database: database,
ComponentName.Schema: schema,
ComponentName.Identifier: identifier
})
new_quote_policy = self.quote_policy.replace_dict(policy)
return self.replace(quote_policy=new_quote_policy)
def include(
self: Self,
database: Optional[bool] = None,
schema: Optional[bool] = None,
identifier: Optional[bool] = None,
) -> Self:
policy = filter_null_values({
ComponentName.Database: database,
ComponentName.Schema: schema,
ComponentName.Identifier: identifier
})
new_include_policy = self.include_policy.replace_dict(policy)
return self.replace(include_policy=new_include_policy)
def information_schema(self, view_name=None) -> 'InformationSchema':
# some of our data comes from jinja, where things can be `Undefined`.
if not isinstance(view_name, str):
view_name = None
# Kick the user-supplied schema out of the information schema relation
# Instead address this as <database>.information_schema by default
info_schema = InformationSchema.from_relation(self, view_name)
return info_schema.incorporate(path={"schema": None})
def information_schema_only(self) -> 'InformationSchema':
return self.information_schema()
def without_identifier(self) -> 'BaseRelation':
"""Return a form of this relation that only has the database and schema
set to included. To get the appropriately-quoted form the schema out of
the result (for use as part of a query), use `.render()`. To get the
raw database or schema name, use `.database` or `.schema`.
The hash of the returned object is the result of render().
"""
return self.include(identifier=False).replace_path(identifier=None)
def _render_iterator(
self
) -> Iterator[Tuple[Optional[ComponentName], Optional[str]]]:
for key in ComponentName:
path_part: Optional[str] = None
if self.include_policy.get_part(key):
path_part = self.path.get_part(key)
if path_part is not None and self.quote_policy.get_part(key):
path_part = self.quoted(path_part)
yield key, path_part
def render(self) -> str:
# if there is nothing set, this will return the empty string.
return '.'.join(
part for _, part in self._render_iterator()
if part is not None
)
def quoted(self, identifier):
return '{quote_char}{identifier}{quote_char}'.format(
quote_char=self.quote_character,
identifier=identifier,
)
@classmethod
def create_from_source(
cls: Type[Self], source: ParsedSourceDefinition, **kwargs: Any
) -> Self:
source_quoting = source.quoting.to_dict(omit_none=True)
source_quoting.pop('column', None)
quote_policy = deep_merge(
cls.get_default_quote_policy().to_dict(omit_none=True),
source_quoting,
kwargs.get('quote_policy', {}),
)
return cls.create(
database=source.database,
schema=source.schema,
identifier=source.identifier,
quote_policy=quote_policy,
**kwargs
)
@staticmethod
def add_ephemeral_prefix(name: str):
return f'__dbt__cte__{name}'
@classmethod
def create_ephemeral_from_node(
cls: Type[Self],
config: HasQuoting,
node: Union[ParsedNode, CompiledNode],
) -> Self:
# Note that ephemeral models are based on the name.
identifier = cls.add_ephemeral_prefix(node.name)
return cls.create(
type=cls.CTE,
identifier=identifier,
).quote(identifier=False)
@classmethod
def create_from_node(
cls: Type[Self],
config: HasQuoting,
node: Union[ParsedNode, CompiledNode],
quote_policy: Optional[Dict[str, bool]] = None,
**kwargs: Any,
) -> Self:
if quote_policy is None:
quote_policy = {}
quote_policy = dbt.utils.merge(config.quoting, quote_policy)
return cls.create(
database=node.database,
schema=node.schema,
identifier=node.alias,
quote_policy=quote_policy,
**kwargs)
@classmethod
def create_from(
cls: Type[Self],
config: HasQuoting,
node: Union[CompiledNode, ParsedNode, ParsedSourceDefinition],
**kwargs: Any,
) -> Self:
if node.resource_type == NodeType.Source:
if not isinstance(node, ParsedSourceDefinition):
raise InternalException(
'type mismatch, expected ParsedSourceDefinition but got {}'
.format(type(node))
)
return cls.create_from_source(node, **kwargs)
else:
if not isinstance(node, (ParsedNode, CompiledNode)):
raise InternalException(
'type mismatch, expected ParsedNode or CompiledNode but '
'got {}'.format(type(node))
)
return cls.create_from_node(config, node, **kwargs)
@classmethod
def create(
cls: Type[Self],
database: Optional[str] = None,
schema: Optional[str] = None,
identifier: Optional[str] = None,
type: Optional[RelationType] = None,
**kwargs,
) -> Self:
kwargs.update({
'path': {
'database': database,
'schema': schema,
'identifier': identifier,
},
'type': type,
})
return cls.from_dict(kwargs)
def __repr__(self) -> str:
return "<{} {}>".format(self.__class__.__name__, self.render())
def __hash__(self) -> int:
return hash(self.render())
def __str__(self) -> str:
return self.render()
@property
def database(self) -> Optional[str]:
return self.path.database
@property
def schema(self) -> Optional[str]:
return self.path.schema
@property
def identifier(self) -> Optional[str]:
return self.path.identifier
@property
def table(self) -> Optional[str]:
return self.path.identifier
# Here for compatibility with old Relation interface
@property
def name(self) -> Optional[str]:
return self.identifier
@property
def is_table(self) -> bool:
return self.type == RelationType.Table
@property
def is_cte(self) -> bool:
return self.type == RelationType.CTE
@property
def is_view(self) -> bool:
return self.type == RelationType.View
@classproperty
def Table(cls) -> str:
return str(RelationType.Table)
@classproperty
def CTE(cls) -> str:
return str(RelationType.CTE)
@classproperty
def View(cls) -> str:
return str(RelationType.View)
@classproperty
def External(cls) -> str:
return str(RelationType.External)
@classproperty
def get_relation_type(cls) -> Type[RelationType]:
return RelationType
Info = TypeVar('Info', bound='InformationSchema')
@dataclass(frozen=True, eq=False, repr=False)
class InformationSchema(BaseRelation):
information_schema_view: Optional[str] = None
def __post_init__(self):
if not isinstance(self.information_schema_view, (type(None), str)):
raise dbt.exceptions.CompilationException(
'Got an invalid name: {}'.format(self.information_schema_view)
)
@classmethod
def get_path(
cls, relation: BaseRelation, information_schema_view: Optional[str]
) -> Path:
return Path(
database=relation.database,
schema=relation.schema,
identifier='INFORMATION_SCHEMA',
)
@classmethod
def get_include_policy(
cls,
relation,
information_schema_view: Optional[str],
) -> Policy:
return relation.include_policy.replace(
database=relation.database is not None,
schema=False,
identifier=True,
)
@classmethod
def get_quote_policy(
cls,
relation,
information_schema_view: Optional[str],
) -> Policy:
return relation.quote_policy.replace(
identifier=False,
)
@classmethod
def from_relation(
cls: Type[Info],
relation: BaseRelation,
information_schema_view: Optional[str],
) -> Info:
include_policy = cls.get_include_policy(
relation, information_schema_view
)
quote_policy = cls.get_quote_policy(relation, information_schema_view)
path = cls.get_path(relation, information_schema_view)
return cls(
type=RelationType.View,
path=path,
include_policy=include_policy,
quote_policy=quote_policy,
information_schema_view=information_schema_view,
)
def _render_iterator(self):
for k, v in super()._render_iterator():
yield k, v
yield None, self.information_schema_view
class SchemaSearchMap(Dict[InformationSchema, Set[Optional[str]]]):
"""A utility class to keep track of what information_schema tables to
search for what schemas. The schema values are all lowercased to avoid
duplication.
"""
def add(self, relation: BaseRelation):
key = relation.information_schema_only()
if key not in self:
self[key] = set()
schema: Optional[str] = None
if relation.schema is not None:
schema = relation.schema.lower()
self[key].add(schema)
def search(
self
) -> Iterator[Tuple[InformationSchema, Optional[str]]]:
for information_schema_name, schemas in self.items():
for schema in schemas:
yield information_schema_name, schema
def flatten(self, allow_multiple_databases: bool = False):
new = self.__class__()
# make sure we don't have multiple databases if allow_multiple_databases is set to False
if not allow_multiple_databases:
seen = {r.database.lower() for r in self if r.database}
if len(seen) > 1:
dbt.exceptions.raise_compiler_error(str(seen))
for information_schema_name, schema in self.search():
path = {
'database': information_schema_name.database,
'schema': schema
}
new.add(information_schema_name.incorporate(
path=path,
quote_policy={'database': False},
include_policy={'database': False},
))
return new