Page Comparison

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event:attr("url").extract(re#httpre#https?://([^/:]+)#)

Note that the syntax above has been deprecated in favor of

event:attrs{"url"}.extract(re#httpre#https?://([^/:]+)#)

Other alternatives

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event:attrs.get("url").extract(re#httpre#https?://([^/:]+)#)

That works because event:attrs evaluates to a KRL map, so that any of Map Operators and expressions can be used with it. As an additional example, if we just wanted to see if the attributes included an attribute named “url” we could use:

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Finally, as one of the matches in a select when we could use (see Event Expressions in the Grammar page):

url re#httpre#https?://([^/:]+)# setting(domain)

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