The r->request_body_no_buffering flag was introduced. It instructs
client request body reading code to avoid reading the whole body, and
to call post_handler early instead. The caller should use the
ngx_http_read_unbuffered_request_body() function to read remaining
parts of the body.
Upstream module is now able to use this mode, if configured with
the proxy_request_buffering directive.
In case of filter finalization, r->upstream might be changed during
the ngx_event_pipe() call. Added an argument to preserve it while
calling the ngx_http_upstream_process_request() function.
A request may be already finalized when ngx_http_upstream_finalize_request()
is called, due to filter finalization: after filter finalization upstream
can be finalized via ngx_http_upstream_cleanup(), either from
ngx_http_terminate_request(), or because a new request was initiated
to an upstream. Then the upstream code will see an error returned from
the filter chain and will call the ngx_http_upstream_finalize_request()
function again.
To prevent corruption of various upstream data in this situation, make sure
to do nothing but merely call ngx_http_finalize_request().
Prodded by Yichun Zhang, for details see the thread at
http://nginx.org/pipermail/nginx-devel/2015-February/006539.html.
When replacing a stale cache entry, its last_modified and etag could be
inherited from the old entry if the response code is not 200 or 206. Moreover,
etag could be inherited with any response code if it's missing in the new
response. As a result, the cache entry is left with invalid last_modified or
etag which could lead to broken revalidation.
For example, when a file is deleted from backend, its last_modified is copied to
the new 404 cache entry and is used later for revalidation. Once the old file
appears again with its original timestamp, revalidation succeeds and the cached
404 response is sent to client instead of the file.
The problem appeared with etags in 44b9ab7752e3 (1.7.3) and affected
last_modified in 1573fc7875fa (1.7.9).
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.
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.
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>
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.
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.
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.
To cache responses with Vary, we now calculate hash of headers listed
in Vary, and return the response from cache only if new request headers
match.
As of now, only one variant of the same resource can be stored in cache.
Due to the u->headers_in.last_modified_time not being correctly initialized,
this variable was evaluated to "Thu, 01 Jan 1970 00:00:00 GMT" for responses
cached without the "Last-Modified" header which resulted in subsequent proxy
requests being sent with "If-Modified-Since: Thu, 01 Jan 1970 00:00:00 GMT"
header.
Signed-off-by: Piotr Sikora <piotr@cloudflare.com>
Previously, a file buffer start position was reset to the file start.
Now it's reset to the previous file buffer end. This fixes
reinitialization of requests having multiple successive parts of a
single file. Such requests are generated by fastcgi module.
The new directives {proxy,fastcgi,scgi,uwsgi,memcached}_next_upstream_tries
and {proxy,fastcgi,scgi,uwsgi,memcached}_next_upstream_timeout limit
the number of upstreams tried and the maximum time spent for these tries
when searching for a valid upstream.
When memory allocation failed in ngx_http_upstream_cache(), the connection
would be terminated directly in ngx_http_upstream_init_request().
Return a INTERNAL_SERVER_ERROR response instead.
Timeout may not be set on an upstream connection when we call
ngx_ssl_handshake() in ngx_http_upstream_ssl_init_connection(),
so make sure to arm it if it's not set.
Based on a patch by Yichun Zhang.
Previously, ngx_http_map_uri_to_path() errors were not checked in
ngx_http_upstream_store(). Moreover, in case of errors temporary
files were not deleted, as u->store was set to 0, preventing cleanup
code in ngx_http_upstream_finalize_request() from removing them. With
this patch, u->store is set to 0 only if there were no errors.
Reported by Feng Gu.
Previously, nginx closed client connection in cases when a response body
from upstream was needed to be cached or stored but shouldn't be sent to
the client. While this is normal for HTTP, it is unacceptable for SPDY.
Fix is to use instead the p->downstream_error flag to prevent nginx from
sending anything downstream. To make this work, the event pipe code was
modified to properly cache empty responses with the flag set.
The ngx_http_upstream_dummy_handler() must be set regardless of
the read event state. This prevents possible additional call of
ngx_http_upstream_send_request_handler().
Previously, last_modified_time was tested against -1 to check if the
not modified filter should be skipped. Notably, this prevented nginx
from additional If-Modified-Since (et al.) checks on proxied responses.
Such behaviour is suboptimal in some cases though, as checks are always
skipped on responses from a cache with ETag only (without Last-Modified),
resulting in If-None-Match being ignored in such cases. Additionally,
it was not possible to return 412 from the If-Unmodified-Since if last
modification time was not known for some reason.
This change introduces explicit r->disable_not_modified flag instead,
which is set by ngx_http_upstream_process_headers().
Previous code in ngx_http_upstream_send_response() used last modified time
from r->headers_out.last_modified_time after the header filter chain was
already called. At this point, last_modified_time may be already cleared,
e.g., with SSI, resulting in incorrect last modified time stored in a
cache file. Fix is to introduce u->headers_in.last_modified_time instead.
Clearing of the r->headers_out.last_modified_time field if a response
isn't cacheable in ngx_http_upstream_send_response() was introduced
in 3b6afa999c2f, the commit to enable not modified filter for cacheable
responses. It doesn't make sense though, as at this point header was
already sent, and not modified filter was already executed. Therefore,
the line was removed to simplify code.
The 7022564a9e0e changeset made ineffective workaround from 2464ccebdb52
to avoid NULL pointer dereference with "if". It is now restored by
moving the u->ssl_name initialization after the check.
Found by Coverity (CID 1210408).