Capturing regexp which excludes two literals

Question

In a Spring controller I want an updateuser endpoint, a deleteuser endpoint and a generic one that captures the rest of options:

@PostMapping(value = "/{action:^((?!(updateuser|deleteuser)).)+}")
// Do something depending on `action`, need to capture the match

@PostMapping(value = "/updateuser")
// Update user

@PostMapping(value = "/deleteuser")
// Delete user

Using that regexp throws:

The number of capturing groups in the pattern segment (^((?!updateuser|deleteuser).)*) does not match the number of URI template variables it defines, which can occur if capturing groups are used in a URI template regex. Use non-capturing groups instead.

I have no problem if I use @PostMapping(value = "/{action:^.*(?!updateuser)}")

Which would be the correct regexp?

Try `^(?:(?!(?:update|delete)user).)+$` or `^(?!.*(?:update|delete)user).+$` — The fourth bird, May 05 '22 at 12:14
`^(?!.*(?:update|delete)user).+$` worked, thanks! If you put in an answer I will mark as accepted. — Eneko, May 05 '22 at 15:54

score 1 · Accepted Answer · answered May 05 '22 at 15:59

You can exclude the updateuser and deleteuser by using a single negative lookahead without a capture group, instead of using a tempered greedy token approach matching a single character followed by the assertion.

^(?!.*(?:update|delete)user).+$

If it should be more strict, you can use word boundaries to prevent partial word matches:

^(?!.*\b(?:update|delete)user\b).+$

See a regex demo.

Capturing regexp which excludes two literals

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