怎么样通过Python实现多任务MySQL转xml功能？
本文实例讲述了Python实现简单的多任务mysql转xml的方法。分享给大家供大家参考，具体如下：
为了需求导出的格式尽量和navicat导出的xml一致。
用的gevent，文件i/o操作会阻塞，所以并不会完全异步。
1. mysql2xml.py：
# -*- coding: utf-8 -*-
'''
Created on 2014/12/27
@author: Yoki
'''
import gevent
import pymysql
from pymysql.cursors import DictCursor
import re
import codecs
db_conn = None
def init_mysql_connect(*args, **kwargs):
global db_conn
db_conn = pymysql.connect(*args, **kwargs)
def list_to_xml(result_cur, key_list):
'''
mysql 结果集转xml，非xml标准导出方式; xml dom 不支持相同名字的node
:param result_cur:
:param key_list:
:return:
'''
content = ''
content += '<?xml version="1.0" encoding="UTF-8" ?>\r\n'
content += '<RECORDS>\r\n' # root节点
for item in result_cur:
content += '\t<RECORD>\r\n'
for k in key_list:
v = item.get(k, '')
real_value = v
content += '\t\t<%s>%s</%s>\r\n' % (k, real_value, k)
content += '\t</RECORD>\r\n'
content += '</RECORDS>\r\n'
return content
def get_table_rows(tb_name):
'''
获取mysql表rows
:param tb_name:
:return:
'''
global db_conn
rows = []
cursor = db_conn.cursor(cursor=DictCursor)
cursor.execute('select * from %s' % tb_name)
for row in cursor:
rows.append(row)
return rows
def get_table_keys(tb_name):
'''
获取表中字段，顺序 为创建表时的顺序
:param tb_name:
:return:
'''
global db_conn
cursor = db_conn.cursor(cursor=DictCursor)
cur = cursor.execute('show create table %s' % tb_name)
if cur != 1:
raise Exception
for r in cursor:
create_sql = r['Create Table']
fields = re.findall('`(.*?)`', create_sql)
result = []
# 处理字段
for i in xrange(1, len(fields)):
field = fields[i]
if field in result:
continue
result.append(field)
return result
return []
def mysql_to_xml(tb_name, output_dir='xml', postfix='xml'):
'''
mysql数据导出xml，
:param tb_name: 数据库表名
:param output_dir:
:param postfix:
:return:
'''
rows = get_table_rows(tb_name)
keys = get_table_keys(tb_name)
content = list_to_xml(rows, keys)
fp = codecs.open('%s/%s.%s' % (output_dir, tb_name, postfix), 'w', 'utf-8')
fp.write(content)
fp.close()
tb_list = [
'tb_item',
'tb_state'
]
if __name__ == '__main__':
init_mysql_connect(host="localhost", user='user', password="password", database='test', port=3306,
charset='utf8')
jobs = []
for tb_name in tb_list:
jobs.append(gevent.spawn(mysql_to_xml, tb_name))
gevent.joinall(jobs)
2. list_to_xml函数修改，速度提升上百倍
def list_to_xml(result_cur, key_list):
fp = codecs.open('test.xml'), 'w', 'utf-8')
fp.write('<?xml version="1.0" encoding="UTF-8" ?>\r\n')
fp.write('<RECORDS>\r\n')
for item in result_cur:
fp.write('\t<RECORD>\r\n')
for k in key_list:
v = item.get(k, '')
if v is None:
real_value = ''
else:
if type(v) == unicode:
real_value = cgi.escape(v)
else:
real_value = v
fp.write('\t\t<%s>%s</%s>\r\n' % (k, real_value, k))
fp.write('\t</RECORD>\r\n')
fp.write('</RECORDS>\r\n')
fp.close()
希望本文所述对大家Python程序设计有所帮助。
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