字符串替换到子进程调用

Question

如何在 Python 中正确执行这个 Unix 命令，将给定的值 index, username, password 代入命令中？

abc.py

import subprocess,datetime
cmd = '\./splunk search "| dbinspect index=%s |timeformat= "%s" rename state as category | stats min(earliestTime) as earliestTime max(latestTime) as latestTime sum(sizeOnDiskMB) as MB by category " -auth %s:%s | grep -v "category" | grep -v "-"' %(index, username, password)

subprocess.call(cmd, shell = True)

当我尝试执行命令时，我得到了错误：

TypeError: not enough arguments for format string

Answer 1

字符串中有四个“%s”格式描述符，(index, username, password) 元组中只有三个元素。

Answer 2

您收到的错误消息非常解释：您有四个 %s 是您的字符串，但您提供的元组中只有三个值。您可能忘记了timeformat 的值吗？

如果需要重用相同的参数，可以使用另一种形式的字符串格式化，使用'some text and {0}'.format(my_string)：

cmd = '\./splunk search "| dbinspect index={0} |timeformat= "{1}" rename state as category | stats min(earliestTime) as earliestTime max(latestTime) as latestTime sum(sizeOnDiskMB) as MB by category " -auth {2}:{3} | grep -v "category" | grep -v "-"'.format(index, timeformat, username, password)