sign-url

Sign urls to protect someone from tampering with it.

This module is a wrapper around crypto.createHmac and simplifies the process of signing urls with dynamic query parameters.

A signed url provides you with the certainty of the origin of that url. For example, a malicious user may try some url hacking in order to discover resources, or even DoS your application by forcing it to unneeded processing and io.

Of course, you'll need to keep track of the <secret> used to sign your urls yourself.

The url parameters, once signed, maybe re-ordered or mangled, internally, they are always normalized, and sorted before signing/signing checks.

Example:

   var url = "http://my.superproject.io?confirm=username@somewhwere.com&expiry=' + Date.now() + 3600000;
   var signed = Sign.url(url, '<SECRET>' );

   // gets you somethign like
   "http://my.superproject.io?confirm=username@somewhere.com&expiry=1392305771282&signature=SrO0X9p27LHFIe7xITBOpetZSpM%3D'