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Issue 825547 link

Starred by 3 users

Issue metadata

Status: Untriaged
Owner: ----
Cc:
Components:
EstimatedDays: ----
NextAction: ----
OS: Linux , Windows , Mac
Pri: 2
Type: Feature



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Send no-cache if a url has no cached assets and protocol is HTTP/2

Reported by skuldw...@gmail.com, Mar 25 2018

Issue description

UserAgent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/65.0.3325.181 Safari/537.36

Example URL:

Steps to reproduce the problem:
N/A

What is the expected behavior?

What went wrong?
When a url has preload link headers it's possible the web server pay push assets the browser already cached.

If browser sent "Cache-Control: no-cache" to the server then this could act as a indicator (to the server) that the browser has no cached assets for the url.

This should be backwards compatible and not break anything existing, but webmasters/developers could check for the no-cache and do a full asset push for the requested url.

A browser could also use no-cache in case it suspects that it has some of the assets for a url (a different page on the same site in the same sub-folder maybe).
This would allow the browser to cherry pick among the preload links in the header instead.

Did this work before? N/A 

Chrome version: 65.0.3325.181  Channel: stable
OS Version: 10.0
Flash Version:
 
Labels: Needs-Triage-M65
Labels: Triaged-ET Needs-Feedback
@Reporter: Please provide sample URL/test case to test this issue from TE end. This would help in further triaging of the issue.

Thanks!

Comment 3 by lassey@google.com, Mar 27 2018

Components: -Internals>Network Internals>Network>Cache Internals>Network>HTTP2

Comment 4 by skuldw...@gmail.com, Mar 31 2018

Sorry, this was meant to be a feature request. Forgot to put "(feature)" at end of subject.

The first line also has typos and is meant to be:
"When a url returns preload link headers it is possible that the web server may push assets the browser already cached."

I can't put up a test as the hosting company's server is apache and a caching proxy is nginx and for some reason PHP is told the protocol is HTTP/1.0 so I can't detect http2.

I'm not sure if $_SERVER['HTTP_PROTOCOL'] can be relied to be HTTP/2.0 or not anyway.

So instead I've attached a crude PHP script of a revised idea to illustrate what I mean.

Cache-Control: h2, no-cache

To indicate that the browser supports (and will accept) http2 push and that it's cache for this url is empty.

I have not done any tests to see if a PHP script is able to properly push however.
index.php
632 bytes View Download
Project Member

Comment 5 by sheriffbot@chromium.org, Mar 31 2018

Cc: sindhu.chelamcherla@chromium.org
Labels: -Needs-Feedback
Thank you for providing more feedback. Adding the requester to the cc list.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot
Cc: vamshi.kommuri@chromium.org
Labels: -Type-Bug M-67 Target-67 FoundIn-67 OS-Linux OS-Mac Type-Feature
Status: Untriaged (was: Unconfirmed)
As per comment#4 by reporter it is understood that this seems to be a feature request, hence changing the type to Feature and marking it as Untriaged.

Thanks!

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