sqlalchemy.ext.serializer fail with column_property in query condition

Deserialization of query with column_property fail with error

Traceback (most recent call last):
  File "/home/mzhukov/projects/test_sqa/test_sql/main.py", line 53, in <module>
    assert str(orig_req) == str(deserialized_obj)
  File "/home/mzhukov/.local/share/virtualenvs/test_sqa-05qMtTeV/lib/python3.7/site-packages/sqlalchemy/orm/query.py", line 3379, in __str__
    return str(context.statement.compile(bind))
  File "<string>", line 1, in <lambda>
  File "/home/mzhukov/.local/share/virtualenvs/test_sqa-05qMtTeV/lib/python3.7/site-packages/sqlalchemy/sql/elements.py", line 462, in compile
    return self._compiler(dialect, bind=bind, **kw)
  File "/home/mzhukov/.local/share/virtualenvs/test_sqa-05qMtTeV/lib/python3.7/site-packages/sqlalchemy/sql/elements.py", line 468, in _compiler
    return dialect.statement_compiler(dialect, self, **kw)
  File "/home/mzhukov/.local/share/virtualenvs/test_sqa-05qMtTeV/lib/python3.7/site-packages/sqlalchemy/sql/compiler.py", line 571, in __init__
    Compiled.__init__(self, dialect, statement, **kwargs)
  File "/home/mzhukov/.local/share/virtualenvs/test_sqa-05qMtTeV/lib/python3.7/site-packages/sqlalchemy/sql/compiler.py", line 319, in __init__
    self.string = self.process(self.statement, **compile_kwargs)
  File "/home/mzhukov/.local/share/virtualenvs/test_sqa-05qMtTeV/lib/python3.7/site-packages/sqlalchemy/sql/compiler.py", line 350, in process
    return obj._compiler_dispatch(self, **kwargs)
  File "/home/mzhukov/.local/share/virtualenvs/test_sqa-05qMtTeV/lib/python3.7/site-packages/sqlalchemy/sql/visitors.py", line 92, in _compiler_dispatch
    return meth(self, **kw)
  File "/home/mzhukov/.local/share/virtualenvs/test_sqa-05qMtTeV/lib/python3.7/site-packages/sqlalchemy/sql/compiler.py", line 2140, in visit_select
    text, select, inner_columns, froms, byfrom, kwargs
  File "/home/mzhukov/.local/share/virtualenvs/test_sqa-05qMtTeV/lib/python3.7/site-packages/sqlalchemy/sql/compiler.py", line 2239, in _compose_select_body
    t = select._whereclause._compiler_dispatch(self, **kwargs)
  File "/home/mzhukov/.local/share/virtualenvs/test_sqa-05qMtTeV/lib/python3.7/site-packages/sqlalchemy/sql/visitors.py", line 92, in _compiler_dispatch
    return meth(self, **kw)
  File "/home/mzhukov/.local/share/virtualenvs/test_sqa-05qMtTeV/lib/python3.7/site-packages/sqlalchemy/sql/compiler.py", line 1299, in visit_binary
    return self._generate_generic_binary(binary, opstring, **kw)
  File "/home/mzhukov/.local/share/virtualenvs/test_sqa-05qMtTeV/lib/python3.7/site-packages/sqlalchemy/sql/compiler.py", line 1346, in _generate_generic_binary
    + binary.right._compiler_dispatch(
  File "/home/mzhukov/.local/share/virtualenvs/test_sqa-05qMtTeV/lib/python3.7/site-packages/sqlalchemy/sql/annotation.py", line 79, in _compiler_dispatch
    return self.__element.__class__._compiler_dispatch(self, visitor, **kw)
  File "/home/mzhukov/.local/share/virtualenvs/test_sqa-05qMtTeV/lib/python3.7/site-packages/sqlalchemy/sql/visitors.py", line 92, in _compiler_dispatch
    return meth(self, **kw)
  File "/home/mzhukov/.local/share/virtualenvs/test_sqa-05qMtTeV/lib/python3.7/site-packages/sqlalchemy/sql/compiler.py", line 836, in visit_label
    self, within_columns_clause=False, **kw
  File "/home/mzhukov/.local/share/virtualenvs/test_sqa-05qMtTeV/lib/python3.7/site-packages/sqlalchemy/sql/visitors.py", line 92, in _compiler_dispatch
    return meth(self, **kw)
  File "/home/mzhukov/.local/share/virtualenvs/test_sqa-05qMtTeV/lib/python3.7/site-packages/sqlalchemy/dialects/sqlite/base.py", line 990, in visit_cast
    return super(SQLiteCompiler, self).visit_cast(cast, **kwargs)
  File "/home/mzhukov/.local/share/virtualenvs/test_sqa-05qMtTeV/lib/python3.7/site-packages/sqlalchemy/sql/compiler.py", line 1015, in visit_cast
    cast.clause._compiler_dispatch(self, **kwargs),
  File "/home/mzhukov/.local/share/virtualenvs/test_sqa-05qMtTeV/lib/python3.7/site-packages/sqlalchemy/sql/visitors.py", line 92, in _compiler_dispatch
    return meth(self, **kw)
  File "/home/mzhukov/.local/share/virtualenvs/test_sqa-05qMtTeV/lib/python3.7/site-packages/sqlalchemy/sql/compiler.py", line 1119, in visit_function
    ) % {"expr": self.function_argspec(func, **kwargs)}
  File "/home/mzhukov/.local/share/virtualenvs/test_sqa-05qMtTeV/lib/python3.7/site-packages/sqlalchemy/sql/compiler.py", line 1131, in function_argspec
    return func.clause_expr._compiler_dispatch(self, **kwargs)
  File "/home/mzhukov/.local/share/virtualenvs/test_sqa-05qMtTeV/lib/python3.7/site-packages/sqlalchemy/sql/visitors.py", line 92, in _compiler_dispatch
    return meth(self, **kw)
  File "/home/mzhukov/.local/share/virtualenvs/test_sqa-05qMtTeV/lib/python3.7/site-packages/sqlalchemy/sql/compiler.py", line 727, in visit_grouping
    return "(" + grouping.element._compiler_dispatch(self, **kwargs) + ")"
  File "/home/mzhukov/.local/share/virtualenvs/test_sqa-05qMtTeV/lib/python3.7/site-packages/sqlalchemy/sql/visitors.py", line 92, in _compiler_dispatch
    return meth(self, **kw)
  File "/home/mzhukov/.local/share/virtualenvs/test_sqa-05qMtTeV/lib/python3.7/site-packages/sqlalchemy/sql/compiler.py", line 983, in visit_clauselist
    c._compiler_dispatch(self, **kw) for c in clauselist.clauses
  File "/home/mzhukov/.local/share/virtualenvs/test_sqa-05qMtTeV/lib/python3.7/site-packages/sqlalchemy/sql/compiler.py", line 981, in <genexpr>
    s
  File "/home/mzhukov/.local/share/virtualenvs/test_sqa-05qMtTeV/lib/python3.7/site-packages/sqlalchemy/sql/compiler.py", line 983, in <genexpr>
    c._compiler_dispatch(self, **kw) for c in clauselist.clauses
  File "/home/mzhukov/.local/share/virtualenvs/test_sqa-05qMtTeV/lib/python3.7/site-packages/sqlalchemy/sql/visitors.py", line 92, in _compiler_dispatch
    return meth(self, **kw)
  File "/home/mzhukov/.local/share/virtualenvs/test_sqa-05qMtTeV/lib/python3.7/site-packages/sqlalchemy/sql/compiler.py", line 1503, in visit_bindparam
    % bindparam.key
sqlalchemy.exc.CompileError: Bind parameter '%(140081294316096 left)s' conflicts with unique bind parameter of the same name

I test this error with Python3.7 + SQLAlchemy 1.3.12 In Python2.7 + SQLAlchemy 1.1.18 deserialization does not work too, but with other exception

For reproducing this bug I make simple test file:

# -*- coding: utf-8 -*-
import pickle
import sys
import traceback

from sqlalchemy import create_engine, Integer, Column, String, exc as sa_exc
from sqlalchemy.ext import serializer
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.ext.hybrid import hybrid_property
from sqlalchemy.orm import sessionmaker, scoped_session, column_property
from sqlalchemy.sql import func

Base = declarative_base()
db_engine = create_engine('sqlite:///:memory:')
Session = scoped_session(sessionmaker(bind=db_engine))


class TestTable(Base):
    __tablename__ = 'test'

    id = Column(Integer, primary_key=True, autoincrement=True)
    _some_id = Column('some_id', String)
    some_primary_id = column_property(func.left(_some_id, 6).cast(Integer))


class SecondTestTable(Base):
    __tablename__ = 'test2'

    id = Column(Integer, primary_key=True, autoincrement=True)
    _some_id = Column('some_id', String)

    @hybrid_property
    def some_primary_id(self):
        return int(self._some_id[:6])

    @some_primary_id.expression
    def some_primary_id(cls):
        return func.left(cls._some_id, 6).cast(Integer)


#  Create tables and two records
Base.metadata.create_all(bind=db_engine)
db_session = Session()
db_session.add(TestTable(_some_id="1234567890"))
db_session.add(SecondTestTable(_some_id="1234567890"))
db_session.commit()

#  Query without column_property in condition work
orig_req = db_session.query(TestTable)
serialised_obj = serializer.dumps(orig_req, pickle.HIGHEST_PROTOCOL)
deserialized_obj = serializer.loads(serialised_obj, metadata=Base.metadata, scoped_session=Session)
assert str(orig_req) == str(deserialized_obj)

#  Query with column_property in condition fail
orig_req = db_session.query(TestTable).filter(TestTable.some_primary_id == 123456)
serialised_obj = serializer.dumps(orig_req, pickle.HIGHEST_PROTOCOL)
deserialized_obj = serializer.loads(serialised_obj, metadata=Base.metadata, scoped_session=Session)
try:
    assert str(orig_req) == str(deserialized_obj)
except sa_exc.SQLAlchemyError as exc:
    print('Error: %r' % exc)
    traceback.print_exc(file=sys.stdout)

#  Query with hybrid_property in condition work
orig_req = db_session.query(SecondTestTable).filter(SecondTestTable.some_primary_id == 123456)
serialised_obj = serializer.dumps(orig_req, pickle.HIGHEST_PROTOCOL)
deserialized_obj = serializer.loads(serialised_obj, metadata=Base.metadata, scoped_session=Session)
assert str(orig_req) == str(deserialized_obj)

[MikhailZhukov]

yes, i think we will do that in nearest future. I replaced all column_property to hybrid_property now and it look like it work good enough while we will refactor code base

[zzzeek]

is it possible that instaed of caching the completed query, you cache the information from the REST request that is used to build up that query? this would be much more portable.