python

基础使用

数据类型

'''
函数不定数量的参数传递
*args 传入的只能是元祖，列表
**kwargs 传入的只能是键值对，字典类型
'''
coll_list = ('1','2')
coll_map = {"a":1,"b":2}
def showCollList(*args):
    for arg in args:
        print("{}的值为{}".format(arg,arg))
def showCollMap(**kwargs):
    for key,value in kwargs.items():
        print("{}的值为{}".format(key,value))
showCollList(*coll_list)
showCollMap(**coll_map)
输出为：
1的值为1
2的值为2
b的值为2
a的值为1

日志-同时输出到前台和文件

import sys
import logging
LOG_FORMAT = "%(asctime)s - %(message)s"
LOG_NAME="script"
logger = logging.getLogger(LOG_NAME)
logger.setLevel(logging.INFO)
console_handler = logging.StreamHandler(sys.stderr)  # 默认是sys.stderr
console_handler.setLevel(logging.INFO)
console_handler.setFormatter(logging.Formatter(LOG_FORMAT))
file_handler = logging.FileHandler(LOG_NAME+'.log')
file_handler.setLevel(logging.INFO)
file_handler.setFormatter(logging.Formatter(LOG_FORMAT))
logger.addHandler(console_handler)
logger.addHandler(file_handler)
logger.info("info")

数据库操作

pymongo

import pymongo
client = pymongo.MongoClient(host="mongodb://root:pass@127.0.0.1:27017/?authSource=admin")
db=client.dbname
collection = db.collectionName

pyredis

import redis
from urllib import parse
redis_url = 'redis://:{}@localhost:6379/1'.format(parse.quote('myredispass'))
pool = redis.ConnectionPool.from_url(redis_url,None,decode_components=True)
r = redis.Redis(connection_pool=pool)
# 批量操作
values=(1,2,3)
with r.pipeline(transaction=False) as pipe:
    for value in values:
        pipe.sadd("redis-set-key", value)
    pipe.execute()
# OR
pipe.sadd("redis-set-key", *values) #这里要使用*args格式，否则会将整个作为一个值存储
'''
增量迭代命令
scan - no keys
sscan - no smembers
hscan - no hgetall
zscan - no zrange
'''
#
print("------set------")
r.sadd("set","004")
r.sadd("set","003")
for item in r.sscan_iter("set"):
    print("item=",item)
#
print("------hash------")
r.hset("hash","a","1")
r.hset("hash","b","2")
r.hset("hash","c","3")
for k,v in r.hscan_iter("hash"):
    print(k,v)
#
print("------zset------")
r.zadd("zset",'a',11,'b',21)
r.zadd("zset",cdef=66,hijk=77)
for k,s in r.zscan_iter("zset"):
    print(k,s)

pymysql

import pymysql.cursors
# 连接数据库
connection = pymysql.connect(host='localhost',
                             user='user',
                             password='passwd',
                             db='db',
                             charset='utf8mb4',
                             cursorclass=pymysql.cursors.DictCursor)
try:
    with connection.cursor() as cursor:
        # 创建一条新的记录
        sql = "INSERT INTO `users` (`email`, `password`) VALUES (%s, %s)"
        cursor.execute(sql, ('webmaster@python.org', 'very-secret'))
    # 连接完数据库并不会自动提交，所以需要手动 commit 你的改动
    connection.commit()
    with connection.cursor() as cursor:
        # 读取单条记录
        sql = "SELECT `id`, `password` FROM `users` WHERE `email`=%s"
        cursor.execute(sql, ('webmaster@python.org',))
        result = cursor.fetchone()
        print(result)
finally:
    connection.close()