Is there some property on req object to get ip's family (IPv4 or IPv6)? Or how can I figure it out? I want to change behavior based on this info. I'm not sure if checking if the string contains a colon is the right way.

CodePudding user response：

You can use the built-in net package for this:

• net.isIPv4(input)
• net.isIPv6(input)

You also have net.isIP(input) which will return 6, 4 or 0 if the parameter is respectively an IPv6, an IPv4, or not an IP.