FastAPI behaving little strange when I hit the API multiple times. Could you help me to resolve it?

[Samba-Odoo-Apps]

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Example Code

class GetDataModelOut(BaseModel):
    count: int = 1
    next: str = None
    previous: str = None
    result: List[dict] = [{}]
    message: str = "Records Found Successfully"
    id: str = None
    statusCode: int = 200

class Emp:
	 @classmethod
    def get_data(cls, request, q, columns):
        records = []
        for record in q:
            data_cols = {col: getattr(record, col) for col in columns}
            records.append(data_cols)
        return records

	 @classmethod
    def get(cls,id,request):
		sch = GetDataModelOut()
		q = request.state.session.query(cls).filter(cls.id == id)
		data = cls.get_data(request, q, ['id','name','sal'])
		for row in data:
            sch.message = "Record found successfully"
            sch.result = [row]
            return sch.__dict__

		
@ROUTER.get("/{emp_id}/")
async def get_employee(emp_id: int, request: Request):
    emp = Emp.get(emp_id, request=request)
    return emp

Description

we are using FAST API to develop the APIs and sql alchemy as ORM. we deployed server in the AWS ubuntu instance host, using gunicorn as web server, nginx redirecting request to gunicorn server. few APIs are behaving strange. For example the API has to return id, name, salary parameters in the response. When I hit that API multiple times, name and id attributes are missing in the result parameter of response for few calls. looking this is the strange behavior from fast API. Any one facing the similar issue. Thanks for your answers in advance. we are not able to reproduce this issue in local system.

Operating System

Linux

Operating System Details

ubuntu on AWS VM

FastAPI Version

0.64

Python Version

3.9

Additional Context

No response

[yinziyan1206]

I guess the problem is not in fastapi but in sqlalchemy. Can you show more details?

[Samba-Odoo-Apps]

are you expecting the session configuration details?
SessionLocal = scoped_session(
sessionmaker(autocommit=False, autoflush=False, bind=engine,
expire_on_commit=False))

@contextmanager
def session_scope():
"""Provide a transactional scope around a series of operations."""
session = SessionLocal()
try:
yield session
session.commit()
except Exception as err:
session.rollback()
raise err
finally:
session.close()

[Samba-Odoo-Apps]

q = request.state.session.query(cls).filter(cls.id == id)
data = cls.get_data(request, q, ['id','name','sal'])

[yinziyan1206]

You can try parsing the results to pydantic model instead of dict. They will be validated by fastapi if the attributes are still missing