需要掌握的知识：
1、函数
2、文件处理
3、tag的用法
4、程序的解耦
需求：
1：查询
2：添加
3：删除
4：修改
5：退出
haproxy.conf 配置文件内容：
1 global 2 log 127.0.0.1 local2 3 daemon 4 maxconn 256 5 log 127.0.0.1 local2 info 6 defaults 7 log global 8 mode http 9 timeout connect 5000ms 10 timeout client 50000ms 11 timeout server 50000ms 12 option dontlognull 13 14 listen stats :8888 15 stats enable 16 stats uri /admin 17 stats auth admin:1234 18 19 frontend oldboy.org 20 bind 0.0.0.0:80 21 option httplog 22 option httpclose 23 option forwardfor 24 log global 25 acl www hdr_reg(host) -i www.oldboy.org 26 use_backend www.oldboy.org if www 27 28 backend www.oldboy1.org 29 server 10.10.0.10 10.10.0.10 weight 9999 maxconn 33333333333 30 server 10.10.10.1 10.10.10.1 weight 22 maxconn 2000 31 server 2.2.2.4 2.2.2.4 weight 20 maxconn 3000 32 backend www.oldboy2.org 33 server 3.3.3.3 3.3.3.3 weight 20 maxconn 3000 34 backend www.oldboy20.org 35 server 10.10.0.10 10.10.0.10 weight 9999 maxconn 33333333333
一、优化后的代码：
1 #!/usr/bin/env python 2 # -*- coding:utf-8 -*- 3 #Author: nulige 4 5 6 import os 7 def file_handle(filename,backend_data,record_list=None,type='fetch'): #type:fetch append change 8 new_file=filename+'_new' 9 bak_file=filename+'_bak' 10 if type == 'fetch': 11 r_list = [] 12 with open(filename, 'r') as f: 13 tag = False 14 for line in f: 15 if line.strip() == backend_data: 16 tag = True 17 continue 18 if tag and line.startswith('backend'): 19 break 20 if tag and line: 21 r_list.append(line.strip()) 22 for line in r_list: 23 print(line) 24 return r_list 25 elif type == 'append': 26 with open(filename, 'r') as read_file, 27 open(new_file, 'w') as write_file: 28 for r_line in read_file: 29 write_file.write(r_line) 30 31 for new_line in record_list: 32 if new_line.startswith('backend'): 33 write_file.write(new_line + ' ') 34 else: 35 write_file.write("%s%s " % (' ' * 8, new_line)) 36 os.rename(filename, bak_file) 37 os.rename(new_file, filename) 38 os.remove(bak_file) 39 elif type == 'change': 40 with open(filename, 'r') as read_file, 41 open(new_file, 'w') as write_file: 42 tag=False 43 has_write=False 44 for r_line in read_file: 45 if r_line.strip() == backend_data: 46 tag=True 47 continue 48 if tag and r_line.startswith('backend'): 49 tag=False 50 if not tag: 51 write_file.write(r_line) 52 else: 53 if not has_write: 54 for new_line in record_list: 55 if new_line.startswith('backend'): 56 write_file.write(new_line+' ') 57 else: 58 write_file.write('%s%s ' %(' '*8,new_line)) 59 has_write=True 60 os.rename(filename, bak_file) 61 os.rename(new_file, filename) 62 os.remove(bak_file) 63 64 65 def fetch(data): 66 backend_data="backend %s" %data 67 return file_handle('haproxy.conf',backend_data,type='fetch') 68 69 def add(data): 70 backend=data['backend'] 71 record_list=fetch(backend) 72 current_record="server %s %s weight %s maxconn %s" %(data['record']['server'], 73 data['record']['server'], 74 data['record']['weight'], 75 data['record']['maxconn']) 76 backend_data="backend %s" %backend 77 78 if not record_list: 79 record_list.append(backend_data) 80 record_list.append(current_record) 81 file_handle('haproxy.conf',backend_data,record_list,type='append') 82 else: 83 record_list.insert(0,backend_data) 84 if current_record not in record_list: 85 record_list.append(current_record) 86 file_handle('haproxy.conf',backend_data,record_list,type='change') 87 88 def remove(data): 89 backend=data['backend'] 90 record_list=fetch(backend) 91 current_record="server %s %s weight %s maxconn %s" %(data['record']['server'], 92 data['record']['server'], 93 data['record']['weight'], 94 data['record']['maxconn']) 95 backend_data = "backend %s" % backend 96 if not record_list or current_record not in record_list: 97 print(' 33[33;1m无此条记录 33[0m') 98 return 99 else: 100 if len(record_list) == 1: #判断record_list是否还有一条记录 101 record_list.remove(current_record) #如果只剩一条记录，就把最后一条记录和backend都删除掉 102 else: 103 record_list.insert(0,backend_data) 104 record_list.remove(current_record) 105 file_handle('haproxy.conf',backend_data,record_list,type='change') 106 107 #{'backend':'www.oldboy20.org','record':{'server':'10.10.0.10','weight':9999,'maxconn':33333333333}} 108 109 def change(data): 110 backend=data[0]['backend'] 111 record_list=fetch(backend) 112 113 old_record="server %s %s weight %s maxconn %s" %(data[0]['record']['server'], 114 data[0]['record']['server'], 115 data[0]['record']['weight'], 116 data[0]['record']['maxconn']) 117 118 new_record = "server %s %s weight %s maxconn %s" % (data[1]['record']['server'], 119 data[1]['record']['server'], 120 data[1]['record']['weight'], 121 data[1]['record']['maxconn']) 122 backend_data="backend %s" %backend 123 124 if not record_list or old_record not in record_list: 125 print(' 33[33;1m无此内容 33[0m') 126 return 127 else: 128 record_list.insert(0,backend_data) 129 index=record_list.index(old_record) 130 record_list[index]=new_record 131 file_handle('haproxy.conf',backend_data,record_list,type='change') 132 133 134 if __name__ == '__main__': 135 msg=''' 136 1：查询 137 2：添加 138 3：删除 139 4：修改 140 5：退出 141 ''' 142 menu_dic={ 143 '1':fetch, 144 '2':add, 145 '3':remove, 146 '4':change, 147 '5':exit, 148 } 149 while True: 150 print(msg) 151 choice=input("操作>>: ").strip() 152 if len(choice) == 0 or choice not in menu_dic:continue 153 if choice == '5':break 154 155 data=input("数据>>: ").strip() 156 157 #menu_dic[choice](data)==fetch(data) 158 if choice != '1': 159 data=eval(data) 160 menu_dic[choice](data) #add(data) 161 162 163 # [{'backend':'www.oldboy20.org','record':{'server':'2.2.2.3','weight':20,'maxconn':3000}},{'backend':'www.oldboy10.org','record':{'server':'10.10.0.10','weight':9999,'maxconn':33333333333}}]
二、分解实现上面过程：
1 #!/usr/bin/env python 2 # -*- coding:utf-8 -*- 3 #Author: nulige 4 5 import os 6 7 #def file_handle(filename,backend_data,record_list=None,type='fetch'): 8 9 #实现查询功能 10 11 def fetch(data): 12 backend_data="backend %s" %data #backend www.oldboy1.org 查找匹配到这行，找到对应的server记录，用字符串拼接的方法 13 record_list=[] #定义一个空列表 14 with open('haproxy.conf','r') as f: #打开haproxy.conf配置文件 15 tag=False #报警器不响 16 for line in f: #去查找文件 17 if line.strip() == backend_data: #把文件的每一行 去掉，才能进行比较，就找到这行backend www.oldboy1.org 18 tag=True #找到人就响警报 19 continue #就跳出这个循环 20 if tag and line.startswith('backend'): #找到下一行的backend,backend www.oldboy2.org 我们就跳出循环 21 break 22 if tag and line: #相当于警报响了 23 record_list.append(line.strip()) #找到了server 10.10.0.10 10.10.0.10 weight 9999 maxconn 33333333333，就要把他加到列表中 24 for line in record_list: 25 print(line) #给用户打印找到的信息 26 return record_list #给用户返回处理的信息 27 28 def add(data): 29 30 backend=data['backend'] 31 record_list=fetch(backend) 32 current_record = "server %s %s weight %s maxconn %s" % (data['record']['server'], 33 data['record']['server'], 34 data['record']['weight'], 35 data['record']['maxconn']) 36 backend_data = "backend %s" % backend 37 38 if not record_list: 39 record_list.append(backend_data) 40 record_list.append(current_record) 41 with open('haproxy.conf','r') as read_file, 42 open('haproxy_new.conf','w') as write_file: 43 for r_line in read_file: 44 write_file.write(r_line) 45 46 for new_line in record_list: 47 if new_line.startswith('backend'): 48 write_file.write(new_line+' ') 49 else: 50 write_file.write("%s%s " %(' '*8,new_line)) 51 52 else: 53 #处理recard_list 54 record_list.insert(0,backend_data) 55 record_list.append(current_record) 56 with open('haproxy.conf','r') as read_file, 57 open('haproxy_new.conf','w') as write_file: 58 tag = False 59 has_write = False 60 for r_line in read_file: 61 if r_line.strip() == backend_data: 62 tag = True 63 continue 64 if tag and r_line.startswith('backend'): 65 tag = False 66 if not tag: 67 write_file.write(r_line) 68 else: 69 if not has_write: 70 for new_line in record_list: 71 if new_line.startswith('backend'): 72 write_file.write(new_line + ' ') 73 else: 74 write_file.write("%s%s " % (' ' * 8, new_line)) 75 has_write = True 76 os.rename('haproxy.conf','haproxy_bak.conf') 77 os.rename('haproxy_new.conf','haproxy.conf') 78 os.remove('haproxy_bak.conf') 79 80 #{'backend':'lhf.oldboy.org','record':{'server':'1.1.1.1','weight':2,'maxconn':200}} 81 82 def remove(data): 83 84 backend=data['backend'] 85 record_list=fetch(backend) 86 current_record = "server %s %s weight %s maxconn %s" % (data['record']['server'], 87 data['record']['server'], 88 data['record']['weight'], 89 data['record']['maxconn']) 90 backend_data = "backend %s" % backend 91 if not record_list and current_record not in record_list: 92 print(' 33[33:[1m无此条记录 33[0]') 93 return 94 else: 95 #处理recard_list 96 record_list.insert(0,backend_data) 97 record_list.remove(current_record) 98 with open('haproxy.conf','r') as read_file, 99 open('haproxy_new.conf','w') as write_file: 100 tag = False 101 has_write = False 102 for r_line in read_file: 103 if r_line.strip() == backend_data: 104 tag = True 105 continue 106 if tag and r_line.startswith('backend'): 107 tag = False 108 if not tag: 109 write_file.write(r_line) 110 else: 111 if not has_write: 112 for new_line in record_list: 113 if new_line.startswith('backend'): 114 write_file.write(new_line + ' ') 115 else: 116 write_file.write("%s%s " % (' ' * 8, new_line)) 117 has_write = True 118 os.rename('haproxy.conf','haproxy_bak.conf') 119 os.rename('haproxy_new.conf','haproxy.conf') 120 os.remove('haproxy_bak.conf') 121 122 #{'backend':'www.oldboy1.org11111','record':{'server':'11.100.200.1','weight':22,'maxconn':200}} 123 124 125 def change(data): 126 backend=data[0]['backend'] #找到要修改的第一条记录 127 record_list=fetch(backend) 128 old_record = "server %s %s weight %s maxconn %s" % (data[0]['record']['server'], 129 data[0]['record']['server'], 130 data[0]['record']['weight'], 131 data[0]['record']['maxconn']) 132 133 new_record = "server %s %s weight %s maxconn %s" % (data[1]['record']['server'], 134 data[1]['record']['server'], 135 data[1]['record']['weight'], 136 data[1]['record']['maxconn']) 137 backend_data = "backend %s" % backend 138 if not record_list and old_record not in record_list: #判断这个文件在原文件中不存在 139 print(' 33[33:[1m无此内容 33[0]') 140 return 141 else: 142 record_list.insert(0,backend_data) #判断文件存在原文件中 143 index=record_list.index(old_record) #求出这个索引 144 record_list[index]=new_record #用新的记录，替换掉旧记录 145 with open('haproxy.conf','r') as read_file, 146 open('haproxy_new.conf','w') as write_file: 147 tag = False 148 has_write = False 149 for r_line in read_file: 150 if r_line.strip() == backend_data: 151 tag = True 152 continue 153 if tag and r_line.startswith('backend'): 154 tag = False 155 if not tag: 156 write_file.write(r_line) 157 else: 158 if not has_write: 159 for new_line in record_list: 160 if new_line.startswith('backend'): 161 write_file.write(new_line + ' ') 162 else: 163 write_file.write("%s%s " % (' ' * 8, new_line)) 164 has_write = True 165 os.rename('haproxy.conf','haproxy_bak.conf') 166 os.rename('haproxy_new.conf','haproxy.conf') 167 os.remove('haproxy_bak.conf') 168 169 #backend www.oldboy2.org 170 #server 3.3.3.3 3.3.3.3 weight 20 maxconn 3000 171 #[{'backend':'www.oldboy2.org','record':{'server':'3.3.3.3','weight':20,'maxconn':3000}},{'backend':'www.oldboy2.org','record':{'server':'10.10.10.10','weight':30,'maxconn':3000000}}] 172 173 def exit(data): 174 pass 175 176 177 if __name__ == '__main__': #__name__是python的内置变量，他会把__name__赋值给__main__ 178 msg=''' 179 1：查询 180 2：添加 181 3：删除 182 4: 修改 183 5：退出 184 ''' 185 # 定义一个字典，key对应fetch函数，其它也相同 186 menu_dic={ 187 '1':fetch, 188 '2':add, 189 '3':remove, 190 '4':change, 191 '5':exit, 192 } 193 while True: #死循环，不断跟用户交互 194 print(msg) #打印出msg信息，让用户选择菜单 195 choice=input("操作>>: ").strip() #去掉空格 196 if len(choice) == 0 or choice not in menu_dic:continue #len(choice)==0,判断他是不是空，choice不在字典里，就跳出这个操作 197 if choice == '5':break 198 199 data=input("数据>>: ").strip() #用户输入的是字符串 200 201 #menu_dic[choice](data)==fetch(data) 202 if choice != '1': #如果输入的不是查询的话，就需要把字符串转换成字典 203 data=eval(data) #因为添加和删除都要求是字典的形式，所以我们要把用户输入的字符串转成字典的形式 204 menu_dic[choice](data) #add(data)