#!/usr/bin/python

import os, subprocess, smtplib
import pymysql.cursors
from email.mime.text import MIMEText

def send_mail(title, msg, from_addr, to_addr, cc_addrs=None):
    if not from_addr or not to_addr:
        return

    mail_title = title
    mail_body  = msg

    new_mail = MIMEText(mail_body)
    new_mail["Subject"] = mail_title
    new_mail["From"] = from_addr
    new_mail["To"] = to_addr

    if cc_addrs != None:
        if isinstance(cc_addrs, str):
            new_mail["Cc"] = cc_addrs
        elif isinstance(cc_addrs, list) and cc_addrs != []:
            new_mail["Cc"] = ','.join(cc_addrs)

    smtp = smtplib.SMTP('localhost')
    smtp.send_message(new_mail)
    smtp.quit()

def send_default_error_mail():
    send_mail(
        "Database connection check",
        "Error, please make some action to recover",
        "送信元メールアドレス",
        "送信先メールアドレス"
    )

connection = pymysql.connect(
    host='ホスト',
    user='ユーザ名',
    password='パスワード',
    db='DB名',
    charset='utf8',
    cursorclass=pymysql.cursors.DictCursor)

if not connection:
    send_default_error_mail()
try:
    with connection.cursor() as cursor:
        sql = "SELECT 1=1"
        cursor.execute(sql)
        results = cursor.fetchall()
        if not results or len(results) == 0:
            send_default_error_mail()
except:
    send_default_error_mail()
finally:
    connection.close