The CrowdHandler pattern matching engine uses POSIX-Extended regular expression syntax.

https://en.wikibooks.org/wiki/Regular_Expressions/POSIX_Basic_Regular_Expressions

https://www.regular-expressions.info/posix.html

https://www.ibm.com/docs/en/watson-explorer/11.0.1?topic=queries-posix-regular-expression-syntax-examples

For example:

.od matches any three-character string ending with "od", including "hod", "mod", and "nod".

[hm]od matches "hod" and "mod".

[^m]od matches all strings matched by .od except "mod".

^[hm]od matches "hod" and "mod", but only at the beginning of the string or line.

[hm]od$ matches "hod" and "mod", but only at the end of the string or line.

\[.\] matches any single character surrounded by "[" and "]" since the brackets are escaped, for example: "[a]" and "[b]".

/(product1|product2)$

Matches:

https://my-domain.com/product1

https://my-domain.com/product2

but NOT

https://my-domain.com/product1/

https://my-domain.com/products/product1

https://my-domain.com/product3


.*\/(product1|product2)\/$

Matches:

https://my-domain.com/product1/

https://my-domain.com/product2/

AND

https://my-domain.com/products/product1/

but NOT

https://my-domain.com/product1

https://my-domain.com/product2

https://my-domain.com/product3


.*\/(product1|product2)\/?$

Matches:

https://my-domain.com/product1

https://my-domain.com/product2

AND

https://my-domain.com/product1

https://my-domain.com/product1/

https://my-domain.com/products/product1

https://my-domain.com/products/product1/

https://my-domain.com/product2

https://my-domain.com/product2/

https://my-domain.com/products/product2

https://my-domain.com/products/product2/

https://my-domain.com/products/details/product1

etc

but NOT

https://my-domain.com/product3

https://my-domain.com/products/product3