How can I print only match pattern word in Terraform

Question

If i got value like

email = "Mark Johnson (mark@johnson.com)"

How can i print only word in the () and output become

mark@johnson.com

Currently I using regex but It seems doesn't work with my pattern

email = regex("x{(,)}", "var.email")

How can i solve this issue , Thanks for your help.

https://stackoverflow.com/questions/42407785/regex-extract-email-from-strings — Ajay Tom George, May 26 '20 at 05:59
That's a strange looking pattern, and doesn't even come close to what you are after. If I may suggest something, possibly a pattern like `(?<=\()[^)]+` or a bit extended with lookahead too will do the job. — JvdV, May 26 '20 at 06:02

score 3 · Answer 1 · answered May 26 '20 at 08:33

Terrafrom used RE2 regex engine, and the regex function returns only the captured value if you define a capturing group in the regex pattern. It will return a list of captures if you have more than one capturing group in your pattern, but here, you need just one.

To extract all text inside parentheses:

> regex("[(]([^()]+)[)]", "Mark Johnson (mark@johnson.com)")

The [(] matches a ( char, ([^()]+) captures into Group 1 any one or more chars into Group 1, and [)] matches a ) char.

To extract an email-like string from parentheses:

> regex("[(]([^()@[:space:]]+@[^()[:space:]]+[.][^()[:space:]]+)[)]", "Mark Johnson (mark@johnson.com)")

Here, [^()@[:space:]]+ matches 1 or more chars other than (, ), @ and whitespace.

See the regex demo

How can I print only match pattern word in Terraform

1 Answers1