import logging
import random
import asynciofrom aiomysql 
import create_pool
# 假設(shè)mysql表分散在8個(gè)host, 每個(gè)host有16張子表
TBLES = {  "192.168.1.01": "table_000-015",
# 000-015表示該ip下的表明從table_000一直連續(xù)到table_015
  "192.168.1.02": "table_016-031", 
   "192.168.1.03": "table_032-047",  
    "192.168.1.04": "table_048-063", 
     "192.168.1.05": "table_064-079",  
     "192.168.1.06": "table_080-095", 
      "192.168.1.07": "table_096-0111", 
       "192.168.1.08": "table_112-0127",
}
USER = "xxx"PASSWD = "xxxx"# wrapper函數(shù)，用于捕捉異常def query_wrapper(func):
  async def wrapper(*args, **kwargs):
    try:
      await func(*args, **kwargs)    except Exception as e:
      print(e)  return wrapper
      # 實(shí)際的sql訪問(wèn)處理函數(shù)，通過(guò)aiomysql實(shí)現(xiàn)異步非阻塞請(qǐng)求@
      query_wrapperasync def query_do_something(ip, db, table):
  async with create_pool(host=ip, db=db, user=USER, password=PASSWD) as pool:
    async with pool.get() as conn:
      async with conn.cursor() as cur:
        sql = ("select xxx from {} where xxxx")
        await cur.execute(sql.format(table))
        res = await cur.fetchall()    
 # then do something...# 生成sql訪問(wèn)隊(duì)列, 隊(duì)列的每個(gè)元素包含要對(duì)某個(gè)表進(jìn)行訪問(wèn)的函數(shù)及參數(shù)def gen_tasks():
  tasks = []  for ip, tbls in TBLES.items():
    cols = re.split('_|-', tbls)
    tblpre = "_".join(cols[:-2])
    min_num = int(cols[-2])
    max_num = int(cols[-1])   
      for num in range(min_num, max_num+1):
      tasks.append(
        (query_do_something, ip, 'your_dbname', '{}_{}'.format(tblpre, num))
      )
 
  random.shuffle(tasks)  
   return tasks# 按批量運(yùn)行sql訪問(wèn)請(qǐng)求隊(duì)列def run_tasks(tasks, batch_len):
  try:  
    for idx in range(0, len(tasks), batch_len):
      batch_tasks = tasks[idx:idx+batch_len]
      logging.info("current batch, start_idx:%s len:%s" % (idx, len(batch_tasks))) 
            for i in range(0, len(batch_tasks)):
        l = batch_tasks[i]
        batch_tasks[i] = asyncio.ensure_future(
          l[0](*l[1:])
        )
      loop.run_until_complete(asyncio.gather(*batch_tasks)) 
       except Exception as e:
    logging.warn(e)# main方法, 通過(guò)asyncio實(shí)現(xiàn)函數(shù)異步調(diào)用def main():
  loop = asyncio.get_event_loop()
 
  tasks = gen_tasks()
  batch_len = len(TBLES.keys()) * 5  # all up to you
  run_tasks(tasks, batch_len)
 
  loop.close()