core/services/db.py

import json
import math
import time
import traceback
import warnings
from typing import Any, Callable, Dict, TypeVar

import sqlalchemy
from sqlalchemy import JSON, Column, Engine, Integer, create_engine, event, exc, func, inspect
from sqlalchemy.orm import Session, configure_mappers, declarative_base
from sqlalchemy.sql.schema import Table

from settings import DB_URL
from utils.logger import root_logger as logger

if DB_URL.startswith("postgres"):
    engine = create_engine(
        DB_URL,
        echo=False,
        pool_size=10,
        max_overflow=20,
        pool_timeout=30,  # Время ожидания свободного соединения
        pool_recycle=1800,  # Время жизни соединения
        pool_pre_ping=True,  # Добавить проверку соединений
        connect_args={
            "sslmode": "disable",
            "connect_timeout": 40,  # Добавить таймаут подключения
        },
    )
else:
    engine = create_engine(DB_URL, echo=False, connect_args={"check_same_thread": False})

inspector = inspect(engine)
configure_mappers()
T = TypeVar("T")
REGISTRY: Dict[str, type] = {}
FILTERED_FIELDS = ["_sa_instance_state", "search_vector"]


def create_table_if_not_exists(engine, table):
    inspector = inspect(engine)
    if table and not inspector.has_table(table.__tablename__):
        table.__table__.create(engine)
        logger.info(f"Table '{table.__tablename__}' created.")
    else:
        logger.info(f"Table '{table.__tablename__}' ok.")


# noinspection PyUnusedLocal
def local_session(src=""):
    return Session(bind=engine, expire_on_commit=False)


class Base(declarative_base()):
    __table__: Table
    __tablename__: str
    __new__: Callable
    __init__: Callable
    __allow_unmapped__ = True
    __abstract__ = True
    __table_args__ = {"extend_existing": True}

    id = Column(Integer, primary_key=True)

    def __init_subclass__(cls, **kwargs):
        REGISTRY[cls.__name__] = cls

    def dict(self) -> Dict[str, Any]:
        column_names = filter(lambda x: x not in FILTERED_FIELDS, self.__table__.columns.keys())
        data = {}
        try:
            for column_name in column_names:
                value = getattr(self, column_name)
                # Check if the value is JSON and decode it if necessary
                if isinstance(value, (str, bytes)) and isinstance(self.__table__.columns[column_name].type, JSON):
                    try:
                        data[column_name] = json.loads(value)
                    except (TypeError, json.JSONDecodeError) as e:
                        logger.error(f"Error decoding JSON for column '{column_name}': {e}")
                        data[column_name] = value
                else:
                    data[column_name] = value
            # Add synthetic field .stat if it exists
            if hasattr(self, "stat"):
                data["stat"] = self.stat
        except Exception as e:
            logger.error(f"Error occurred while converting object to dictionary: {e}")
        return data

    def update(self, values: Dict[str, Any]) -> None:
        for key, value in values.items():
            if hasattr(self, key):
                setattr(self, key, value)


# make_searchable(Base.metadata)
# Base.metadata.create_all(bind=engine)


# Функция для вывода полного трейсбека при предупреждениях
def warning_with_traceback(message: Warning | str, category, filename: str, lineno: int, file=None, line=None):
    tb = traceback.format_stack()
    tb_str = "".join(tb)
    return f"{message} ({filename}, {lineno}): {category.__name__}\n{tb_str}"


# Установка функции вывода трейсбека для предупреждений SQLAlchemy
warnings.showwarning = warning_with_traceback
warnings.simplefilter("always", exc.SAWarning)


# Функция для извлечения SQL-запроса из контекста
def get_statement_from_context(context):
    query = ""
    compiled = context.compiled
    if compiled:
        compiled_statement = compiled.string
        compiled_parameters = compiled.params
        if compiled_statement:
            if compiled_parameters:
                try:
                    # Безопасное форматирование параметров
                    query = compiled_statement % compiled_parameters
                except Exception as e:
                    logger.error(f"Error formatting query: {e}")
            else:
                query = compiled_statement
    if query:
        query = query.replace("\n", " ").replace("  ", " ").replace("  ", " ").strip()
    return query


# Обработчик события перед выполнением запроса
@event.listens_for(Engine, "before_cursor_execute")
def before_cursor_execute(conn, cursor, statement, parameters, context, executemany):
    conn.query_start_time = time.time()
    conn.cursor_id = id(cursor)  # Отслеживание конкретного курсора


# Обработчик события после выполнения запроса
@event.listens_for(Engine, "after_cursor_execute")
def after_cursor_execute(conn, cursor, statement, parameters, context, executemany):
    if hasattr(conn, "cursor_id") and conn.cursor_id == id(cursor):
        query = get_statement_from_context(context)
        if query:
            elapsed = time.time() - conn.query_start_time
            if elapsed > 1:
                query_end = query[-16:]
                query = query.split(query_end)[0] + query_end
                logger.debug(query)
                elapsed_n = math.floor(elapsed)
                logger.debug("*" * (elapsed_n))
                logger.debug(f"{elapsed:.3f} s")
        del conn.cursor_id  # Удаление идентификатора курсора после выполнения


def get_json_builder():
    """
    Возвращает подходящие функции для построения JSON объектов в зависимости от драйвера БД
    """
    dialect = engine.dialect.name
    json_cast = lambda x: x  # noqa: E731
    if dialect.startswith("postgres"):
        json_cast = lambda x: func.cast(x, sqlalchemy.Text)  # noqa: E731
        return func.json_build_object, func.json_agg, json_cast
    elif dialect.startswith("sqlite") or dialect.startswith("mysql"):
        return func.json_object, func.json_group_array, json_cast
    else:
        raise NotImplementedError(f"JSON builder not implemented for dialect {dialect}")


# Используем их в коде
json_builder, json_array_builder, json_cast = get_json_builder()