如何使用re2正则表达式否定字符串模式? [英] How to negate string pattern using re2 regex?

问题描述

我正在使用Google re2 正则表达式来查询 Prometheus 在Grafana仪表板上.尝试通过以下3种可能的输入字符串从键中获取价值

I'm using google re2 regex for the purpose of querying Prometheus on Grafana dashboard. Trying to get value from key by below 3 types of possible input strings

 1. object{one="ab-vwxc",two="value1",key="abcd-eest-ed-xyz-bnn",four="obsoleteValues"}
 2. object{one="ab-vwxc",two="value1",key="abcd-eest-xyz-bnn",four="obsoleteValues"}
 3. object{one="ab-vwxc",two="value1",key="abcd-eest-xyz-bnn-ed",four="obsoleteValues"}

..具有以下所列的验证

..with validation as listed below

• 应包含abcd-
• 不应包含-ed

• should contain abcd-
• shouldn't contain -ed

以某种方式此正则表达式

\bkey="(abcd(?:-\w+)*[^-][^e][^d]\w)"

..满足第一个条件abcd-，但不满足第二个条件(取反-ed).

..satisfies the first condition abcd- but couldn't satisfy the second condition (negating -ed).

第二个输入选项的预期输出为abcd-eest-xyz-bnn.任何帮助将非常感激.非常感谢.

The expected output would be abcd-eest-xyz-bnn from the 2nd input option. Any help would be really appreciated. Thanks a lot.

推荐答案

如果我正确理解了您的要求，则以下模式应该有效:

If I understand your requirements correctly, the following pattern should work:

\bkey="(abcd(?:-e|-(?:[^e\W]|e[^d\W])\w*)*)"

演示 .

Demo.

重要部分的故障:

(?:                 # Start a non-capturing group.
    -e              # Match '-e' literally.
    |               # Or the following...
    -               # Match '-' literally.
    (?:             # Start a second non-capturing group.
        [^e\W]      # Match any word character except 'e'.
        |           # Or...
        e[^d\W]     # Match 'e' followed by any word character except 'd'.
    )               # Close non-capturing group.
    \w*             # Match zero or more additional word characters.
)                   # Close non-capturing group.

或者简单地说:

匹配连字符，然后:

Match a hyphen followed by:

• 仅字母"e". 或..
• 不是开头的单词 ^* . 或..
• 以'e'开头的单词，后面没有'd'.

• only the letter 'e'. Or..
• a word^* not starting with 'e'. Or..
• a word starting with 'e' not followed by 'd'.

---

^* _{一个单词"这里是指正则表达式中定义的一串字字符.}

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