An extension for sqlalchemy to store the session object in context and simplify the retrieval of the query result.
from sqlalchemy.ext.asyncio import create_async_engine
from sqlalchemy_tx_context import SQLAlchemyTransactionContext
engine = create_async_engine(...)
db = SQLAlchemyTransactionContext(engine)SQLAlchemyTransactionContext contains the following methods for creating queries with execution
through a context session:
selectinsertupdatedeleteunionunion_allexists
Query will use a session from the context.
async def some_repository_method():
await db.insert(...).values(...).execute()
async def some_function():
async with db.transaction() as tx:
await some_repository_method()
await tx.rollback() # Record will not be insertedIf there is no session in the context, a default session will be created to execute a single query.
async def some_repository_method():
await db.insert(...).values(...).execute()
async def some_function():
await some_repository_method()Calling the transaction method inside the session will create a nested transaction.
async def some_function():
async with db.transaction() as tx1:
isinstance(tx1, AsyncSession) # True
async with db.transaction() as tx2:
isinstance(tx2, AsyncSessionTransaction) # TrueList of proxy methods added to the request object
Proxy methods for the AsyncSession properties:
executescalarscalars
Example:
value = await db.select(...).execute()The same as:
async with async_sessionmaker(engine).begin() as tx:
result = await tx.execute(select(...))Proxy methods for the Result properties:
firstall
Example:
value = await db.select(...).first()The same as:
async with async_sessionmaker(engine).begin() as tx:
result = await tx.execute(select(...))
value = result.first()Proxy methods for the MappingResult properties:
mapped_firstmapped_onemapped_all
Example:
value = await db.select(...).mapped_first()The same as:
async with async_sessionmaker(engine).begin() as tx:
result = await tx.execute(select(...))
value = result.mappings().first()Proxy method for the CursorResult:
rowcount
