Fiddler is a proxy server; it shows any traffic sent to it. It will show traffic from any browser to any remote server (regardless of the server technology). It will show traffic from
a server (e.g. an ASP.NET page, Node.js app, etc) if that server is configured to proxy its requests.
For a Node.js request, see, for instance: http://stackoverflow.com/questions/8697344/can-a-proxy-like-fiddler-be-used-with-node-jss-clientrequest
... the exact details depend on which of the myriad HTTP libraries you're using to issue requests from the node script.
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