This reduces layering violation and simplifies the logic of AIO preread, since
it's now triggered by the send chain function itself without falling back to
the copy filter. The context of AIO operation is now stored per file buffer,
which makes it possible to properly handle cases when multiple buffers come
from different locations, each with its own configuration.
If fastcgi_pass (or any look-alike that doesn't imply a default
port) is specified as an IP literal (as opposed to a hostname),
port absence was not detected at configuration time and could
result in EADDRNOTAVAIL at run time.
Fixed this in such a way that configs like
http {
server {
location / {
fastcgi_pass 127.0.0.1;
}
}
upstream 127.0.0.1 {
server 10.0.0.1:12345;
}
}
still work. That is, port absence check is delayed until after
we make sure there's no explicit upstream with such a name.
If use_temp_path is set to off, a subdirectory "temp" is created in the cache
directory. It's used instead of proxy_temp_path and friends for caching
upstream response.
Some parts of code related to handling variants of a resource moved into
a separate function that is called earlier. This allows to use cache file
name as a prefix for temporary file in the following patch.
The configuration handling code has changed to look similar to the proxy_store
directive and friends. This simplifies adding variable support in the following
patch.
No functional changes.
Currently, storing and caching mechanisms cannot work together, and a
configuration error is thrown when the proxy_store and proxy_cache
directives (as well as their friends) are configured on the same level.
But configurations like in the example below were allowed and could result
in critical errors in the error log:
proxy_store on;
location / {
proxy_cache one;
}
Only proxy_store worked in this case.
For more predictable and errorless behavior these directives now prevent
each other from being inherited from the previous level.
This changes internal API related to handling of the "store"
flag in ngx_http_upstream_conf_t. Previously, a non-null value
of "store_lengths" was enough to enable store functionality with
custom path. Now, the "store" flag is also required to be set.
No functional changes.
The proxy_store, fastcgi_store, scgi_store and uwsgi_store were inherited
incorrectly if a directive with variables was defined, and then redefined
to the "on" value, i.e. in configurations like:
proxy_store /data/www$upstream_http_x_store;
location / {
proxy_store on;
}
In the following configuration request was sent to a backend without
URI changed to '/' due to if:
location /proxy-pass-uri {
proxy_pass http://127.0.0.1:8080/;
set $true 1;
if ($true) {
# nothing
}
}
Fix is to inherit conf->location from the location where proxy_pass was
configured, much like it's done with conf->vars.
The proxy_pass directive and other handlers are not expected to be inherited
into nested locations, but there is a special code to inherit upstream
handlers into limit_except blocks, as well as a configuration into if{}
blocks. This caused incorrect behaviour in configurations with nested
locations and limit_except blocks, like this:
location / {
proxy_pass http://u;
location /inner/ {
# no proxy_pass here
limit_except GET {
# nothing
}
}
}
In such a configuration the limit_except block inside "location /inner/"
unexpectedly used proxy_pass defined in "location /", while it shouldn't.
Fix is to avoid inheritance of conf->upstream.upstream (and
conf->proxy_lengths) into locations which don't have noname flag.
Instead of independant inheritance of conf->upstream.upstream (proxy_pass
without variables) and conf->proxy_lengths (proxy_pass with variables)
we now test them both and inherit only if neither is set. Additionally,
SSL context is also inherited only in this case now.
Based on the patch by Alexey Radkov.
RFC7232 says:
The 304 (Not Modified) status code indicates that a conditional GET
or HEAD request has been received and would have resulted in a 200
(OK) response if it were not for the fact that the condition
evaluated to false.
which means that there is no reason to send requests with "If-None-Match"
and/or "If-Modified-Since" headers for responses cached with other status
codes.
Also, sending conditional requests for responses cached with other status
codes could result in a strange behavior, e.g. upstream server returning
304 Not Modified for cached 404 Not Found responses, etc.
Signed-off-by: Piotr Sikora <piotr@cloudflare.com>
In case of a cache lock timeout and in the aio handler we now call
r->write_event_handler() instead of a connection write handler,
to make sure to run appropriate subrequest. Previous code failed to run
inactive subrequests and hence resulted in suboptimal behaviour, see
report by Yichun Zhang:
http://mailman.nginx.org/pipermail/nginx-devel/2013-October/004435.html
(Infinite hang claimed in the report seems impossible without 3rd party
modules, as subrequests will be eventually woken up by the postpone filter.)
To ensure proper logging make sure to set current_request in all event
handlers, including resolve, ssl handshake, cache lock wait timer and
aio read handlers. A macro ngx_http_set_log_request() introduced to
simplify this.
The alert was introduced in 03ff14058272 (1.5.4), and was triggered on each
post_action invocation.
There is no real need to call header filters in case of post_action,
so return NGX_OK from ngx_http_send_header() if r->post_action is set.
This helps to avoid delays in sending the last chunk of data because
of bad interaction between Nagle's algorithm on nginx side and
delayed ACK on the client side.
Delays could also be caused by TCP_CORK/TCP_NOPUSH if SPDY was
working without SSL and sendfile() was used.
The upstream modules remove and alter a number of client headers
before sending the request to upstream. This set of headers is
smaller or even empty when cache is disabled.
It's still possible that a request in a cache-enabled location is
uncached, for example, if cache entry counter is below min_uses.
In this case it's better to alter a smaller set of headers and
pass more client headers to backend unchanged. One of the benefits
is enabling server-side byte ranges in such requests.
Once this age is reached, the cache lock is discarded and another
request can acquire the lock. Requests which failed to acquire
the lock are not allowed to cache the response.
For further progress a new buffer must be at least two bytes larger than
the remaining unparsed data. One more byte is needed for null-termination
and another one for further progress. Otherwise inflate() fails with
Z_BUF_ERROR.
Previously, nginx would emit empty values in a header with multiple,
NULL-separated values.
This is forbidden by the SPDY specification, which requires headers to
have either a single (possibly empty) value or multiple, NULL-separated
non-empty values.
Signed-off-by: Piotr Sikora <piotr@cloudflare.com>
When got multiple upstream IP addresses using DNS resolving, the number of
upstreams tries and the maxinum time spent for these tries were not affected.
This patch fixed it.
Spaces in Accept-Charset, Accept-Encoding, and Accept-Language headers
are now ignored. As per syntax of these headers spaces can only appear
in places where they are optional.
If a variant stored can't be used to respond to a request, the variant
hash is used as a secondary key.
Additionally, if we previously switched to a secondary key, while storing
a response to cache we check if the variant hash still apply. If not, we
switch back to the original key, to handle cases when Vary changes.
