Opened 8 years ago
Last modified 5 years ago
#1188 new enhancement
Send "immutable" keyword in Cache-Control when "expires max"
Reported by: | Owned by: | ||
---|---|---|---|
Priority: | minor | Milestone: | |
Component: | nginx-module | Version: | 1.11.x |
Keywords: | Cc: | ||
uname -a: | SunOS mordac 5.11 joyent_20160218T022556Z i86pc i386 i86pc | ||
nginx -V: |
nginx version: nginx/1.11.8
built by gcc 6.3.0 (GCC) built with OpenSSL 1.1.0c 10 Nov 2016 TLS SNI support enabled configure arguments: --prefix=/usr/local --conf-path=/usr/local/etc/nginx --with-ipv6 --with-http_ssl_module --with-http_realip_module --with-select_module --with-poll_module --with-http_stub_status_module --with-http_gzip_static_module --without-http_scgi_module --without-http_uwsgi_module --with-cc-opt='-I/usr/local/include -I/usr/local/ssl/include -DNGINX_DTRACE=1' --with-ld-opt='-L /usr/local/lib -L /usr/local/ssl/lib' --error-log-path=/tmp/nginx_error.log --with-http_v2_module --with-http_auth_request_module --with-stream |
Description
Per the documentation for ngx_http_headers_module:
The max parameter sets “Expires” to the value “Thu, 31 Dec 2037 23:55:55 GMT”,
and “Cache-Control” to 10 years.
At Facebook's urging, Firefox implemented an additional keyword to Cache-Control for immutable assets:
https://code.facebook.com/posts/557147474482256/this-browser-tweak-saved-60-of-requests-to-facebook/
https://hacks.mozilla.org/2017/01/using-immutable-caching-to-speed-up-the-web/
Adding this "immutable" keyword to the Cache-Control header for "expires max" requests would improve cache effectiveness for Firefox users.
The change itself is trivial:
--- src/http/modules/ngx_http_headers_filter_module.c.dist Thu Jan 26 11:14:29 2017 +++ src/http/modules/ngx_http_headers_filter_module.c Thu Jan 26 11:15:23 2017 @@ -301,7 +301,7 @@ if (expires == NGX_HTTP_EXPIRES_MAX) { e->value.data = (u_char *) "Thu, 31 Dec 2037 23:55:55 GMT"; /* 10 years */ - ngx_str_set(&cc->value, "max-age=315360000"); + ngx_str_set(&cc->value, "max-age=315360000, immutable"); return NGX_OK; }
Change History (4)
follow-up: 2 comment:1 by , 8 years ago
comment:2 by , 7 years ago
Replying to ru:
What's wrong with
add_header Cache-Control immutable;
?
Primarily because of:
Inheritance Rules for add_header Directives
NGINX configuration blocks inherit add_header directives from their enclosing blocks, so you just need to place the add_header directive in the top-level server block. There’s one important exception: if a block includes an add_header directive itself, it does not inherit headers from enclosing blocks, and you need to redeclare all add_header directives:
From: https://www.nginx.com/blog/http-strict-transport-security-hsts-and-nginx/
I replaced "expires max" with two add_header directives for Expires and Cache-Control which disabled add_header directives that were set elsewhere, notably for Strict-Transport-Security and X-Frame-Options.
comment:3 by , 6 years ago
Cache-Control: ...,immutable;
support is also in Webkit: https://bugs.webkit.org/show_bug.cgi?id=167497
Edge appears to have it since v15: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Cache-Control
(Chromium is wontfix: https://bugs.chromium.org/p/chromium/issues/detail?id=611416 )
I think this would be great to add with expires max
and I (naïvely) can't see any downside :D
comment:4 by , 5 years ago
I've created ngx_immutable module so one can specify immutable on;
in lieu of expires max;
.
What's wrong with
add_header Cache-Control immutable;
?