ETL过程跑完后，使用python发送邮件

目标库中，如果有行数为0的表，使用python发送邮件

# -*- coding:utf-8 -*-
# Author: zjc
# Description:send monitor info to someone.
# Date: 20170718

import contextlib
import pymysql
import smtplib

from email.mime.text import MIMEText

# 监控信息变量
TABLE_SCHEMA_LIST = ('db-name1', 'db-name2')
COLUMN_LIST = "table_schema,table_name,table_type,table_rows,table_comment"

# 邮箱信息变量
MAIL_HOST = "smtp.xxxxx.com"  # set you mail host
#定义成列表，实现全局变量功能
MAIL_SUBJECT = ["XX - MONITOR "]
MAIL_SENDER_NAME = "1234567@qq.com"
MAIL_SENDER_PASSWORD = "******"
MAIL_RECEIVERS = ["asdfghj@XXX.com","eqerqreq@163.com"]
MAIL_MESSAGE_BEGIN = """
<p>ETL结果信息</p>
    <table border="1">
        <tr>
            <th>table_schema</th>
            <th>table_name</th>
            <th>table_rows</th>
            <th>table_comment</th>
        </tr>
"""
MAIL_MESSAGE_END = """
    </table>
"""

# 邮局发送函数
def sendMailTo(message):
    msg = MIMEText(message, 'html', 'utf-8')
    msg['Subject'] = MAIL_SUBJECT[0]
    try:
        server = smtplib.SMTP()
        server.connect(MAIL_HOST)
        server.login(MAIL_SENDER_NAME, MAIL_SENDER_PASSWORD)
        server.sendmail(MAIL_SENDER_NAME, MAIL_RECEIVERS, msg.as_string())
        server.close()
        #print("邮件发送成功")
        return True
    except smtplib.SMTPException:
        #print("Error: 无法发送邮件")
        raise

# 定义数据库连接，上下文管理器，连接后自动关闭连接
@contextlib.contextmanager
def mysql(host='10.0.8.*', user='', password='*****',
                                 db='', port=3306, charset='utf8mb4'):
  conn = pymysql.connect(host=host, port=port, user=user, passwd=password, db=db, charset=charset)
  cursor = conn.cursor(cursor=pymysql.cursors.DictCursor)
  try:
    yield cursor
  finally:
    conn.commit()
    cursor.close()
    conn.close()

# 查询 MySql 元数据信息
def query_schema_table_info():
    resultlist = []
    # Connect to the database
    with mysql() as cursor:
        # Read a single record
        sql = "select "+ COLUMN_LIST + " FROM information_schema.TABLES " \
              "WHERE TABLE_SCHEMA IN "+str(TABLE_SCHEMA_LIST)
        #print(sql)
        cursor.execute(sql)
        for row in cursor.fetchall():
            resultlist.append(row)
    return resultlist

# 根据查询结果，判断数据抽取是否正常
def deal():
    mess = ""
    zero_table_count = 0
    result_list = query_schema_table_info()
    for r in result_list:
            # 总体情况
            if r["table_rows"] == 0:
                mess += "<tr bgcolor='red''>" \
                       + " <td>" + r["table_schema"] + "</td>" \
                       + " <td>" + r["table_name"] + "</td>" \
                       + " <td>" + str(r["table_rows"]) + "</td>" \
                       + " <td>" + r["table_comment"] + "</td>" \
                       + " </tr>"
            else:
                mess += "<tr>" \
                       + " <td>" + r["table_schema"] + "</td>" \
                       + " <td>" + r["table_name"] + "</td>" \
                       + " <td>" + str(r["table_rows"]) + "</td>" \
                       + " <td>" + r["table_comment"] + "</td>" \
                       + " </tr>"

            if r["table_rows"] == 0:
                zero_table_count += 1

    # 如果多于0个表是空的，则表示数据出问题了
    if zero_table_count > 0:
        MAIL_SUBJECT[0] = " - MONITOR 发生错误"
    #print(mess)
    #print(MAIL_SUBJECT[0])
    return mess

# print(query_schema_table_info())
if __name__ == '__main__':
    message = MAIL_MESSAGE_BEGIN + deal() + MAIL_MESSAGE_END
    sendMailTo(message)

===================

放到到服务器运行可能错误：

报错一：

UnicodeDecodeError: 'ascii' codec can't decode byte 0xe9 in position 0: ordinal not in range(128)

1、原因

因为默认情况下，Python采用的是ascii编码方式，如下所示：

python -c "import sys; print sys.getdefaultencoding()"  ascii

而Python在进行编码方式之间的转换时，会将 unicode 作为“中间编码”，但 unicode 最大只有 128 那么长，所以这里当尝试将 ascii 编码字符串转换成"中间编码" unicode 时由于超出了其范围，就报出了如上错误。

2、解决办法

1）第一种：这里我们将Python的默认编码方式修改为utf-8，就可以规避上述问题的发生，具体方式，我们在Python文件的前面加上如下代码：

import sys
defaultencoding = 'utf-8'
if sys.getdefaultencoding() != defaultencoding:
    reload(sys)
    sys.setdefaultencoding(defaultencoding)

2）第二种：我们在/usr/lib/python2.7/site-packages/目录下添加一个sitecustomize.py文件，内容如下：

import sys sys.setdefaultencoding('utf-8')