Weaken outgoing ETags

[dougwilson]

When the response is compressed, alter any ETag response header to make it a weak ETag.

This is the easiest solution to deal with ETags. It's also what nginx did semi-recently to solve this (before their patch, they always dropped the ETag header completely) in http://trac.nginx.org/nginx/changeset/e491b26fa5a1908eb22dd96d19b4d26e25eeca2c/nginx

[mickaeltr]

Hello @dougwilson,

I noticed that strong ETags (generated by Express) are the same for compressed and uncompressed responses. Is it somehow possible to generate a different strong ETag when the response is compressed?

My use-case: we have an Express application => nginx => Akamai

• Akamai only supports strong ETags
• if the compression is done by nginx, it sets a weak ETag => FAIL
• if the compression is done by Express, it sends the same (strong) ETag as for the uncompressed response => FAIL

Thank you