regex - 如何在bash中使用grep命令解析以下日期

Question

json 文件中的给定日期为 "ts":"2021-04-23T13:11:57Z"或 "2021-05-05T07:22:54+05:00"我想使用 grep 读取字符串。
需要帮助形成最后一部分的正则表达式，即时区。
我当前的命令就像grep -Po '"ts":"\K([0-9]{4}-[0-9]{2}-[0-9]{2}T[0-2][0-9]:[0-5][0-9]:[0-5][0-9]+Z这适用于第一种格式我如何修改它以便它适用于两种格式..

Answer 1

使用您展示的 GNU 样本 grep的 PCRE 选项，您可以尝试按照正则表达式来匹配两个时间。grep -oP '(?:"ts":)?"\d{4}-\d{2}-\d{2}T(?:[0-1][1-9]|2[0-4]):(?:[0-4][0-9]|5[0-9])[+:](?:[0-4][0-9]|5[0-9])(?:Z"|\+(?:[0-4][0-9]|5[0-9]):(?:[0-4][0-9]|5[0-9])")' Input_file 说明:为上述添加详细说明。

(?:"ts":)?                ##In a non-capturing group matching "ts": keeping it optional here.
"\d{4}-\d{2}-\d{2}T       ##Matching " followed by 4 digits-2digits-2digits T here.
(?:                       ##Starting 1st non-capturing group here.
   [0-1][1-9]|2[0-4]      ##Matching 0 to 19 and 20 to 24 here to cover 24 hours.
):                        ##Closing 1st non-capturing group followed by colon here.
(?:                       ##Starting 2nd non-capturing group here.
   [0-4][0-9]|5[0-9]      ##Matching 00 to 59 for mins here.
)                         ##Closing 2nd non-capturing group here.
[+:]                      ##Matching either + or : here.
(?:                       ##Starting 3rd capturing group here.
   [0-4][0-9]|5[0-9]      ##Matching 00 to 59 for seconds here.
)                         ##Closing 3rd non-capturing group here.
(?:                       ##Starting 4th non-capturing group here.
   Z"|\+                  ##Matching Z" OR +(literal character) here.
   (?:                    ##Starting non-capturing group here.
     [0-4][0-9]|5[0-9]    ##Matching 00 to 59 here.
   )                      ##Closing non-capturing group here.
   :                      ##Matching colon here.
   (?:                    ##Starting non-capturing group here.
     [0-4][0-9]|5[0-9]    ##Matching 00 to 59 here.
   )"                     ##Closing non-capturing group here, followed by "
)                         ##Closing 4th non-capturing group here.