FastAPI Pagination

Pagination Pattern

class PaginatedResponse(BaseModel, Generic[T]):
    data:     list[T]
    total:    int
    page:     int
    per_page: int
    pages:    int

def paginate(query, page: int, per_page: int):
    total = query.count()
    items = query.offset((page-1)*per_page).limit(per_page).all()
    return PaginatedResponse(data=items, total=total, page=page,
        per_page=per_page, pages=-(-total//per_page))

@app.get("/users", response_model=PaginatedResponse[UserResponse])
def list_users(page: int = Query(1, ge=1), per_page: int = Query(10, ge=1, le=100), db = Depends(get_db)):
    return paginate(db.query(User), page, per_page)