UnmappedClassError is a class within the sqlalchemy.orm.exc module of the SQLAlchemy project.
NoResultFound
and
UnmappedInstanceError
are a couple of other callables within the sqlalchemy.orm.exc package that also have code examples.
flask-sqlalchemy (project documentation and PyPI information) is a Flask extension that makes it easier to use SQLAlchemy when building Flask apps. flask-sqlalchemy provides helper functions that reduce the amount of common boilerplate code that you have to frequently write yourself if you did not use this library when combining Flask with SQLAlchemy.
flask-sqlalchemy is provided as open source under the BSD 3-Clause "New" or "Revised" License.
flask-sqlalchemy / src/flask_sqlalchemy / init.py
# __init__.py
import functools
import os
import sys
import warnings
from math import ceil
from operator import itemgetter
from threading import Lock
from time import perf_counter
import sqlalchemy
from flask import _app_ctx_stack
from flask import abort
from flask import current_app
from flask import request
from flask.signals import Namespace
from sqlalchemy import event
from sqlalchemy import inspect
from sqlalchemy import orm
from sqlalchemy.engine.url import make_url
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.ext.declarative import DeclarativeMeta
from sqlalchemy.orm.exc import UnmappedClassError
from sqlalchemy.orm.session import Session as SessionBase
from .model import DefaultMeta
from .model import Model
__version__ = "3.0.0.dev"
_signals = Namespace()
models_committed = _signals.signal("models-committed")
before_models_committed = _signals.signal("before-models-committed")
def _make_table(db):
def _make_table(*args, **kwargs):
if len(args) > 1 and isinstance(args[1], db.Column):
args = (args[0], db.metadata) + args[1:]
info = kwargs.pop("info", None) or {}
info.setdefault("bind_key", None)
kwargs["info"] = info
return sqlalchemy.Table(*args, **kwargs)
return _make_table
## ... source file abbreviated to get to UnmappedClassError examples ...
else:
per_page = 20
items = self.limit(per_page).offset((page - 1) * per_page).all()
if not items and page != 1 and error_out:
abort(404)
if not count:
total = None
else:
total = self.order_by(None).count()
return Pagination(self, page, per_page, total, items)
class _QueryProperty:
def __init__(self, sa):
self.sa = sa
def __get__(self, obj, type):
try:
mapper = orm.class_mapper(type)
if mapper:
return type.query_class(mapper, session=self.sa.session())
except UnmappedClassError:
return None
def _record_queries(app):
if app.debug:
return True
rq = app.config["SQLALCHEMY_RECORD_QUERIES"]
if rq is not None:
return rq
return bool(app.config.get("TESTING"))
class _EngineConnector:
def __init__(self, sa, app, bind=None):
self._sa = sa
self._app = app
self._engine = None
self._connected_for = None
self._bind = bind
self._lock = Lock()
def get_uri(self):
if self._bind is None:
return self._app.config["SQLALCHEMY_DATABASE_URI"]
## ... source file continues with no further UnmappedClassError examples...
graphene-sqlalchemy (project documentation and PyPI package information) is a SQLAlchemy integration for Graphene, which makes it easier to build GraphQL-based APIs into Python web applications. The package allows you to subclass SQLAlchemy classes and build queries around them with custom code to match the backend queries with the GraphQL-based request queries. The project is provided as open source under the MIT license.
graphene-sqlalchemy / graphene_sqlalchemy / utils.py
# utils.py
import re
import warnings
from sqlalchemy.exc import ArgumentError
from sqlalchemy.orm import class_mapper, object_mapper
from sqlalchemy.orm.exc import UnmappedClassError, UnmappedInstanceError
def get_session(context):
return context.get("session")
def get_query(model, context):
query = getattr(model, "query", None)
if not query:
session = get_session(context)
if not session:
raise Exception(
"A query in the model Base or a session in the schema is required for querying.\n"
"Read more http://docs.graphene-python.org/projects/sqlalchemy/en/latest/tips/#querying"
)
query = session.query(model)
return query
def is_mapped_class(cls):
try:
class_mapper(cls)
except (ArgumentError, UnmappedClassError):
return False
else:
return True
def is_mapped_instance(cls):
try:
object_mapper(cls)
except (ArgumentError, UnmappedInstanceError):
return False
else:
return True
def to_type_name(name):
return "".join(part[:1].upper() + part[1:] for part in name.split("_"))
_re_enum_value_name_1 = re.compile("(.)([A-Z][a-z]+)")
_re_enum_value_name_2 = re.compile("([a-z0-9])([A-Z])")
def to_enum_value_name(name):
return _re_enum_value_name_2.sub(
## ... source file continues with no further UnmappedClassError examples...