Tornado使用协程异步访问mysql工具：TorMysql

Posted 2021-04-20 饭前码字

最重要一点：

Tormysql的增删改查都会起一个事务，所以即使是查询，也需要最后显式commit；之前在使用的时候就没注意，导致mysql积压了一堆操作，看起来的现象是各种对mysql的操作都延时了。

import tormysql
import pymysql.cursors

from tornado import gen

pool = tormysql.ConnectionPool(
    max_connections=500,  # max open connections
    idle_seconds=7500,  # connection idle timeout time, 0 is not timeout
    wait_connection_timeout=600,  # wait connection timeout
    host="x.x.x.x",
    user="xxxx",
    passwd="passxxx",
    db="test_db",
    charset="utf8",
    cursorclass=pymysql.cursors.DictCursor  # 获取的是字典形式， 没有这句获取的是元组
)


class Mysql:
    def __init__(self, table):
        self.table = table

    @gen.coroutine
    def fetch(self, select_items, where_items):
        table = self.table
        with (yield pool.Connection()) as conn:
            try:
                with conn.cursor() as cursor:
                    data_count = yield cursor.execute(f"SELECT {select_items} FROM {table} where 1 {where_items}")
                    resp = cursor.fetchall()
            except:
                raise gen.Return(None)
            else:
                yield conn.commit()
                raise gen.Return(resp)

    @gen.coroutine
    def put(self, new_val_map, where_items):
        table = self.table
        with (yield pool.Connection()) as conn:
            try:
                with conn.cursor() as cursor:
                    data_count = yield cursor.execute(f"UPDATE {table} SET {new_val_map} where 1 {where_items}")
            except:
                yield conn.rollback()
                raise gen.Return(False)
            else:
                yield conn.commit()
                raise gen.Return(True)

    @gen.coroutine
    def post(self, fileds, new_val):
        table = self.table
        with (yield pool.Connection()) as conn:
            try:
                with conn.cursor() as cursor:
                    data_count = yield cursor.execute(f"INSERT INTO {table} {fileds} VALUES {new_val}")
                    new_id = cursor.lastrowid
            except:
                yield conn.rollback()
                raise gen.Return(False)
            else:
                yield conn.commit()
                raise gen.Return(True)