flag+文件操作

#!/usr/bin/env python
# -*- coding:utf-8 -*-
import json
import os

def fetch(backend):
backend_title = 'backend %s' % backend
record_list = []
with open('ha') as obj:
flag = False
for line in obj:
line = line.strip()
if line == backend_title:
flag = True
continue
if flag and line.startswith('backend'):
flag = False
break

if flag and line:
record_list.append(line)

return record_list

def add(dict_info):
backend = dict_info.get('backend')
record_list = fetch(backend)
backend_title = "backend %s" % backend
current_record = "server %s %s weight %d maxconn %d" % (dict_info['record']['server'], dict_info['record']['server'], dict_info['record']['weight'], dict_info['record']['maxconn'])
if not record_list:
record_list.append(backend_title)
record_list.append(current_record)
with open('ha') as read_file, open('ha.new', 'w') as write_file:
flag = False
for line in read_file:
write_file.write(line)
for i in record_list:
if i.startswith('backend'):
write_file.write(i+'\n')
else:
write_file.write("%s%s\n" % (8*" ", i))
else:
record_list.insert(0, backend_title)
if current_record not in record_list:
record_list.append(current_record)

with open('ha') as read_file, open('ha.new', 'w') as write_file:
flag = False
has_write = False
for line in read_file:
line_strip = line.strip()
if line_strip == backend_title:
flag = True
continue
if flag and line_strip.startswith('backend'):
flag = False
if not flag:
write_file.write(line)
else:
if not has_write:
for i in record_list:
if i.startswith('backend'):
write_file.write(i+'\n')
else:
write_file.write("%s%s\n" % (8*" ", i))
has_write = True
os.rename('ha','ha.bak')
os.rename('ha.new','ha')

def remove(dict_info):
backend = dict_info.get('backend')
record_list = fetch(backend)
backend_title = "backend %s" % backend
current_record = "server %s %s weight %d maxconn %d" % (dict_info['record']['server'], dict_info['record']['server'], dict_info['record']['weight'], dict_info['record']['maxconn'])
if not record_list:
return
else:
if current_record not in record_list:
return
else:
del record_list[record_list.index(current_record)]
if len(record_list) > 0:
record_list.insert(0, backend_title)
with open('ha') as read_file, open('ha.new', 'w') as write_file:
flag = False
has_write = False
for line in read_file:
line_strip = line.strip()
if line_strip == backend_title:
flag = True
continue
if flag and line_strip.startswith('backend'):
flag = False
if not flag:
write_file.write(line)
else:
if not has_write:
for i in record_list:
if i.startswith('backend'):
write_file.write(i+'\n')
else:
write_file.write("%s%s\n" % (8*" ", i))
has_write = True
os.rename('ha','ha.bak')
os.rename('ha.new','ha')

if __name__ == '__main__':
"""
print '1、获取；2、添加；3、删除'
num = raw_input('请输入序号：')
data = raw_input('请输入内容：')
if num == '1':
fetch(data)
else:
dict_data = json.loads(data)
if num == '2':
add(dict_data)
elif num == '3':
remove(dict_data)
else:
pass
"""
#data = "www.oldboy.org"
#fetch(data)
#data = '{"backend": "tettst.oldboy.org","record":{"server": "100.1.7.90","weight": 20,"maxconn": 30}}'
#dict_data = json.loads(data)
#add(dict_data)
#remove(dict_data)

demo