#!/usr/bin/env python

# -*- encoding: utf8 -*-

import calendar

import time

import os

import sys

from datetime import datetime,timedelta

import mysql.connector

# 定义一些全局变量

work_dir = "G:/"

argv_var_name=sys.argv

argv_database_name =""

argv_table_name = ""

getdbconfig_0_152 = {

    'host': '127.0.0.1',

    'user': 'root',

    'password': 'root',

    'port': '3306'

}

# 此函数用来打印输出制定内容，第一个变量是输出内容，第二个变量是文件前缀，第三个变量是后缀名

def print_log(print_content,db_name,filename,suffix):

    my_log_day = time.strftime("%Y%m%d")

    my_log_file="%s%s_%s_%s.%s" %(work_dir,db_name,filename,my_log_day,suffix)

    #with open(my_log_file, "aw") as f:

    with open(my_log_file, "a") as f:

        f.write( print_content+"\n")

        f.close()

# 此函数用来指定某个月增加一个月

def add_month(srcDate, addMonths):

    if not srcDate or not srcDate:

        pass

    if addMonths < 1:

        return srcDate

    month = srcDate.month - 1 + addMonths

    year = srcDate.year + month / 12

    month = month % 12 + 1

    day = min(srcDate.day, calendar.monthrange(year, month)[1])

    return srcDate.replace(year=year, month=month, day=day)

def select_any_sql(getdbconfig,select_sql):

    select_any_sql_cnn = mysql.connector.connect(host=getdbconfig['host'] , user=getdbconfig['user'], password=getdbconfig['password'],port=getdbconfig['port'])

    select_any_sql_cursor = select_any_sql_cnn.cursor()

    select_any_sql_cursor.execute(select_sql)

    select_any_sql_data = select_any_sql_cursor.fetchone()

    select_any_sql_cnn.close

    return select_any_sql_data

# 此函数用来导入数据

def import_dump_sql(getdbconfig, dumpsql):

    import_host = getdbconfig['host']

    import_db = getdbconfig['database']

    import_user = getdbconfig['user']

    import_password = getdbconfig['password']

    import_port = getdbconfig['port']

    mysqlimport = " mysql -h%s -u%s -p%s -P%s %s  < %s  " % (import_host, import_user, import_password, import_port, import_db, dumpsql)

    os.system(mysqlimport)

def select_partition(getdbconfig):

    if len(argv_var_name) == 1:

        argv_database_name = ""

        argv_table_name = ""

    elif len(argv_var_name) == 2:

        argv_database_name = argv_var_name[1]

        argv_table_name = ""

    elif len(argv_var_name) == 3:

        argv_database_name = argv_var_name[1]

        argv_table_name = argv_var_name[2]

    else:

        print "Warning!!!! up to three parameters can be specified!!!!"

    if argv_database_name == "":

        partition_info_table_schema = ""

    else:

        partition_info_table_schema = "and table_schema='%s'" % (argv_database_name)

    if argv_table_name == "":

        partition_info_table_name = ""

    else:

        partition_info_table_name = "and table_name='%s'" %(argv_table_name)

    select_partition_sql = "SELECT table_schema,table_name,PARTITION_NAME,PARTITION_ORDINAL_POSITION,PARTITION_METHOD,PARTITION_EXPRESSION,PARTITION_DESCRIPTION FROM information_schema.`PARTITIONS` " \

                           "WHERE table_schema not in ('information_schema','performance_schema','mysql','test','sqlexe') %s %s and PARTITION_NAME is not null order by table_schema,PARTITION_NAME, PARTITION_ORDINAL_POSITION;" %(partition_info_table_schema,partition_info_table_name)

    partition_contain_before = ()

    partition_info = []

    auto_create_partition_filename=[]

    partition_info_not_in_range=[]

    cnn = mysql.connector.connect(**getdbconfig)

    cursor = cnn.cursor()

    cursor.execute(select_partition_sql)

    for (table_schema, table_name, PARTITION_NAME, PARTITION_ORDINAL_POSITION, PARTITION_METHOD, PARTITION_EXPRESSION,PARTITION_DESCRIPTION) in cursor:

        PARTITION_ORDINAL_POSITION_NUM = int(PARTITION_ORDINAL_POSITION) - 1

        if PARTITION_DESCRIPTION == 'MAXVALUE':

            select_paritition_description_sql = "SELECT PARTITION_NAME AS PARTITION_NAME_BEFORE,PARTITION_DESCRIPTION AS PARTITION_DESCRIPTION_BEFORE FROM information_schema.`PARTITIONS` " \

                                                "WHERE table_schema='%s' and table_name='%s'  and PARTITION_ORDINAL_POSITION='%s' ;" % (table_schema, table_name, PARTITION_ORDINAL_POSITION_NUM)

            mysql_select_cnn = mysql.connector.connect(**getdbconfig)

            mysql_select_cursor = mysql_select_cnn.cursor()

            mysql_select_cursor.execute(select_paritition_description_sql)

            for (PARTITION_NAME_BEFORE, PARTITION_DESCRIPTION_BEFORE) in mysql_select_cursor:

                partition_contain_before = (table_schema, table_name, PARTITION_NAME, PARTITION_NAME_BEFORE, PARTITION_METHOD,PARTITION_DESCRIPTION, PARTITION_DESCRIPTION_BEFORE)

                partition_info.append(partition_contain_before)

            mysql_select_cnn.close

    if len(partition_info) == 0:

        print "PARTITION in the Database does not exist!!!"

    else:

        for i in partition_info:

            #print "database:", i[0]

            if i[4] == 'RANGE':

                # 此部分数据用于生成alter table drop 语句  alter table t_lgj_log add PARTITION(PARTITION p201804 VALUES LESS THAN (737150));

                select_max_partition_name_sql = "select count(*) as COUNT from %s.%s partition(%s)" % (i[0], i[1], i[2])

                max_partition_name_count = select_any_sql(getdbconfig, select_max_partition_name_sql)[0]

                if max_partition_name_count==0:

                    prompt_database="-- database : %s" %(i[0])

                    print_log(prompt_database,i[0], "auto_create_partition", "sql")

                    print_user_database="use %s;" %(i[0])

                    print_log(print_user_database, i[0],"auto_create_partition", "sql")

                    sql_alter_table_drop_partition = "alter table %s.%s drop PARTITION  %s;" % (i[0], i[1], i[2])

                    # auto_create_partition 指的是用于自动删除最大分区并添加分区的脚本

                    print_log(sql_alter_table_drop_partition,i[0], "auto_create_partition", "sql")

                else:

                    return_info_can_not_drop_max_partition = "%s.%s.%s" % (i[0], i[1], i[2])

                    # can_not_drop_max_partition 指的是最大分区中有数据，然后这部分数据并不能直接删除，把这些分区信息记录下来

                    print_log(return_info_can_not_drop_max_partition, i[0],"can_not_drop_max_partition", "sql")

                # 此部分数据用于生成alter table add 语句  alter table t_lgj_log add PARTITION(PARTITION p201804 VALUES LESS THAN (737150));

                select_next_paritition_description_name="select from_days(%s);" %(i[6])

                maxvalue_date=add_month(select_any_sql(getdbconfig, select_next_paritition_description_name)[0],1).strftime('%Y-%m-%d')

                maxvalue_date_year_month=add_month(select_any_sql(getdbconfig, select_next_paritition_description_name)[0],1).strftime('%Y%m')

                add_partition_name_01="p%s" %(maxvalue_date_year_month)

                # 此部分用于判断生成的 PARTITION_NAME 是否已经存在，如果存在，则需要在月份上加1

                if add_partition_name_01 == i[3]:

                    add_partition_name=add_partition_name_01

                else:

                    maxvalue_date_year_month_01=add_month(add_month(select_any_sql(getdbconfig, select_next_paritition_description_name)[0],1),1).strftime('%Y%m')

                    add_partition_name = "p%s" % (maxvalue_date_year_month_01)

                less_than_sql="select to_days('%s')" %(maxvalue_date)

                less_than_name=select_any_sql(getdbconfig,less_than_sql)[0]

                sql_alter_table_add_partition="alter table %s.%s add  PARTITION(PARTITION  %s VALUES LESS THAN (%s));" %(i[0], i[1],add_partition_name,less_than_name)

                print_log(sql_alter_table_add_partition, i[0],"auto_create_partition", "sql")

            else:

                # can_not_drop_max_partition 指的是分区规则并不是range分区，把这些分区信息记录下来

                print_log(i, i[0],"partition_info_not_in_range", "sql")

            # 记录保存的文件名到auto_create_partition_filename 列表

            my_log_day = time.strftime("%Y%m%d")

            partition_filename="%s_%s_%s.sql" %(i[0],"auto_create_partition",my_log_day)

            auto_create_partition_filename.append(partition_filename)

    cnn.close

    # auto_create_partition_filename 列表记录了保存可以执行SQL文件名，如果列表不为空，直接调用 import_dump_sql 函数执行里面的SQL ，其中不同的库保存在不同的文件

    if len(auto_create_partition_filename)>0:

        for i in auto_create_partition_filename:

            filename="%s%s" %(work_dir,i)

            #import_dump_sql(getdbconfig,filename)

            print "Done!!!", filename

    else:

        print "PARTITION in the Database does not exist!!!"

select_partition(getdbconfig_0_152)