pip install fastapi-sa-orm-filter

from fastapi import FastAPI
from fastapi.params import Query
from fastapi_sa_orm_filter.main import FilterCore
from fastapi_sa_orm_filter.operators import Operators as ops

from db.base import get_session
from db.models import MyModel


app = FastAPI()

# Define fields and operators for filter
my_objects_filter = {
    'my_model_field_name': [ops.eq, ops.in_],
    'my_model_field_name': [ops.between, ops.eq, ops.gt, ops.lt, ops.in_],
    'my_model_field_name': [ops.like, ops.startswith, ops.contains, ops.in_],
    'my_model_field_name': [ops.between, ops.not_eq, ops.gte, ops.lte]
}

@app.get("/")
async def get_filtered_objects(
    filter_query: str = Query(default=''),
    db: AsyncSession = Depends(get_session)
 ) -> List[MyModel]:
    my_filter = FilterCore(MyModel, my_objects_filter)
    query = my_filter.get_query(filter_query)
    res = await db.execute(query)
    return res.scalars().all()

# Input query string
'''
salary_from__in_=60,70,80&
created_at__between=2023-05-01,2023-05-05|
category__eq=Medicine&
order_by=-id,category
'''

   
# Returned SQLAlchemy orm query exact as:
           
select(model)
    .where(
        or_(
            and_(
                model.salary_from.in_(60,70,80),
                model.created_at.between(2023-05-01, 2023-05-05)
            ),
            model.category == 'Medicine'
        ).order_by(model.id.desc(), model.category.asc())

# Create a class inherited from FilterCore and rewrite 'get_unordered_query' method.
# 0.2.0 Version

class CustomFilter(FilterCore):

    def get_select_query_part(self):
        custom_select = select(
            self.model.id,
            self.model.is_active,
            func.sum(self.model.salary_from).label("sum_salary_from"),
            self.model.category
        )
        return custom_select

    def get_group_by_query_part(self):
        return [self.model.is_active]


# 0.1.5 Version
# Original method is:
def get_unordered_query(self, conditions):
    unordered_query = select(self._model).filter(or_(*conditions))
    return unordered_query
    
# Rewrite example:
class CustomFilter(FilterCore):

    def get_unordered_query(self, conditions):
        unordered_query = select(
            self.model.field_name1,
            self.model.field_name2,
            func.sum(self.model.field_name3).label("field_name3"),
            self.model.field_name4
        ).filter(or_(*conditions)).group_by(self.model.field_name2)
        return unordered_query