处理 couchdb 通知的外部进程导致崩溃

Question

我在通过 python 脚本处理对 couchdb 数据库的更改时遇到问题。

data = 'test'
f = open('/home/username/test','w')
f.write(data + '\n')
f.close()

这是我尝试运行的脚本（用于测试目的）。它叫做 "list.py"，它位于“/usr/local/src/couchdb”中。我在我的“/etc/couchdb”文件夹中修改我的 "local.ini" 添加：

[update_notification]
list = python /usr/local/src/couchdb/list.py

每次进行修改时都应调用此脚本，但它会导致 couchdb 在我启动服务器后几乎立即崩溃。这是错误日志（我认为）。

 [Sat, 24 Oct 2015 23:05:09 GMT] [error] [<0.6468.0>] {error_report,<0.31.0>,
                  {<0.6468.0>,crash_report,
                   [[{initial_call,
                      {couch_os_process,init,['Argument__1']}},
                     {pid,<0.6468.0>},
                     {registered_name,[]},
                     {error_info,
                      {exit,
                       {exit_status,1},
                       [{gen_server,terminate,6,
                         [{file,"gen_server.erl"},{line,744}]},
                        {proc_lib,init_p_do_apply,3,
                         [{file,"proc_lib.erl"},{line,239}]}]}},
                     {ancestors,
                      [couch_db_update,couch_primary_services,
                       couch_server_sup,<0.32.0>]},
                     {messages,[]},
                     {links,[<0.5922.0>]},
                     {dictionary,[]},
                     {trap_exit,false},
                     {status,running},
                     {heap_size,987},
                     {stack_size,27},
                     {reductions,884}],
                    []]}}

 [Sat, 24 Oct 2015 23:05:09 GMT] [error] [<0.5922.0>] Update notification 
 process <0.6468.0> died: {exit_status,

 [Sat, 24 Oct 2015 23:05:09 GMT] [error] [<0.6430.0>] {error_report,<0.31.0>,
                  {<0.6430.0>,supervisor_report,
                   [{supervisor,{local,couch_db_update_notifier_sup}},
                    {errorContext,child_terminated},
                    {reason,normal},
                    {offender,
                     [{pid,<0.6467.0>},
                      {name,"list"},
                      {mfargs,
                       {couch_db_update_notifier,start_link,
                        ["python /usr/local/src/couchdb/list.py"]}},
                      {restart_type,permanent},
                      {shutdown,1000},
                      {child_type,supervisor}]}]}}

 [Sat, 24 Oct 2015 23:05:09 GMT] [error] [<0.6472.0>] ** Generic server <0.6472.0> terminating 
** Last message in was {#Port<0.5590>,{exit_status,1}}
** When Server state == {os_proc,"python /usr/local/src/couchdb/list.py",
                             #Port<0.5590>,
                             #Fun<couch_os_process.2.14837184>,
                             #Fun<couch_os_process.3.14837184>,5000}
** Reason for termination == 
** {exit_status,1}

我错过了什么？非常感谢

Answer 1

couchdb 进程是否有权 read/write 访问脚本中的文件？它可能归您所有，而 couchdb 进程可能无权写入它

Answer 2

所以，似乎在 couchdb 中处理通知的外部进程需要一个无限循环，每次出现时都会读取标准输入，否则它不起作用。

import sys

line = str(sys.stdin.readline())
while line:
    print(line)
    line = sys.stdin.readline()

例如此代码 (python) 读取每个通知并打印它...

处理 couchdb 通知的外部进程导致崩溃

External process to handle couchdb notification causes crash

python

crash

couchdb

process