Jmeter - getting 401 unauthorized error after login

Question

I have to record a large test plan including 4 transactional controllers and response assertions for the UI side but at the time of login there is token generated and I am doing correlation manually.

I have used the regular expression extractor to extract the token from my login response but it gives the following error:

org.apache.oro.text.MalformedCachePatternException: Invalid expression: (?<=("|')token("|'):("|'))(.*?)("|')(=?) Sequence (?<...) not recognized.

Please guide me also how can I pass this TOKEN on the further request as each request has its own header manager. How I can pass THIS TOKEN OVER 4 TRANSACTIONAL CONTROLLER. I am adding my test plan for reference. Please guide me on a suitable process to do this.

Answer 1

The exception clearly states that Sequence (?<...) not recognized

As per jmeter documentation https://jmeter.apache.org/usermanual/regular_expressions.html, Lookbehind expression (?<=) is not supported.

So use:

("|')token("|'):("|')(.*?)("|')

Here we have 5 groups, the actual token is in the 4th group and to get just the token value set template field as: $4$