Refactor db infra to require instantiating object

This commit is contained in:
Tim Van Baak 2021-05-04 23:05:03 -07:00
parent fc28718846
commit 9f2c9d14d3
1 changed files with 36 additions and 34 deletions

View File

@ -6,43 +6,31 @@ import sqlite3
import uuid
# Register GUID as a known type with sqlite
sqlite3.register_converter('GUID', lambda h: uuid.UUID(hex=h))
sqlite3.register_adapter(uuid.UUID, lambda u: u.hex)
class Uuid(TypeDecorator):
"""
A uuid backed by a char(32) field in sqlite.
"""
impl = CHAR(32)
"""
A uuid backed by a char(32) field in sqlite.
"""
impl = CHAR(32)
def process_bind_param(self, value, dialect):
if value is None:
return value
elif not isinstance(value, uuid.UUID):
return f'{uuid.UUID(value).int:32x}'
else:
return f'{value.int:32x}'
def process_bind_param(self, value, dialect):
if value is None:
return value
elif not isinstance(value, uuid.UUID):
return f'{uuid.UUID(value).int:32x}'
else:
return f'{value.int:32x}'
def process_result_value(self, value, dialect):
if value is None:
return value
elif not isinstance(value, uuid.UUID):
return uuid.UUID(value)
else:
return value
def process_result_value(self, value, dialect):
if value is None:
return value
elif not isinstance(value, uuid.UUID):
return uuid.UUID(value)
else:
return value
engine = create_engine('sqlite:///:memory:', connect_args={'detect_types': sqlite3.PARSE_DECLTYPES})
# Enable foreign key constraints
@event.listens_for(engine, "connect")
def set_sqlite_pragma(dbapi_connection, connection_record):
cursor = dbapi_connection.cursor()
cursor.execute("PRAGMA foreign_keys=ON")
cursor.close()
# Define naming conventions for generated constraints
metadata = MetaData(bind=engine, naming_convention={
metadata = MetaData(naming_convention={
"ix": "ix_%(column_0_label)s",
"uq": "uq_%(table_name)s_%(column_0_name)s",
"ck": "ck_%(table_name)s_%(constraint_name)s",
@ -50,8 +38,22 @@ metadata = MetaData(bind=engine, naming_convention={
"pk": "pk_%(table_name)s"
})
# Thread-safe db session
session = scoped_session(sessionmaker(bind=engine))
# Base class for ORM models
ModelBase = declarative_base(metadata=metadata)
class DbContext():
def __init__(self, db_uri, debug=False):
# Create an engine and enable foreign key constraints in sqlite
self.engine = create_engine(db_uri, echo=debug)
@event.listens_for(self.engine, "connect")
def set_sqlite_pragma(dbapi_connection, connection_record):
cursor = dbapi_connection.cursor()
cursor.execute("PRAGMA foreign_keys=ON")
cursor.close()
# Create a thread-safe session factory
self.session = scoped_session(sessionmaker(bind=self.engine))
def create_all(self):
ModelBase.metadata.create_all(self.engine)