nginx_substitutions_filter Note: this module is not distributed with the Nginx source. Installation instructions can be found below.
Description nginx_substitutions_filter is a filter module which can do both regular expression and fixed string substitutions on response bodies. This module is quite different from the Nginx's native Substitution Module. It scans the output chains buffer and matches string line by line, just like Apache's mod_substitute (http://httpd.apache.org/docs/trunk/mod/mod_substitute.html).
Example location / {
subs_filter_types text/html text/css text/xml;
subs_filter st(\d*).example.com $1.example.com ir;
subs_filter a.example.com s.example.com;
subs_filter http://$host https://$host;
}
Directives
subs_filter_types
subs_filter
subs_filter_types syntax: subs_filter_types mime-type [mime-types]
default: subs_filter_types text/html
context: http, server, location
subs_filter_types is used to specify which content types should be checked for subs_filter, in addition to text/html. The default is only text/html.
This module just works with plain text. If the response is compressed, it can't uncompress the response and will ignore this response. This module can be compatible with gzip filter module. But it will not work with proxy compressed response. You can disable the compressed response like this:
proxy_set_header Accept-Encoding "";
subs_filter syntax: subs_filter source_str destination_str [gior]
default: none
context: http, server, location
subs_filter allows replacing source string(regular expression or fixed) in the nginx response with destination string. The variables in matching text is only avaiable under fixed string mode, which means the matching text could not contain variables if it is a regular expression. Substitution text may contain variables. More than one substitution rules per location is supported. The meaning of the third flags are:
g(default): Replace all the match strings.
i: Perform a case-insensitive match.
o: Just replace the first one.
r: The pattern is treated as a regular expression, default is fixed string.
subs_filter_bypass syntax: subs_filter_bypass $variable1 ...
default: none
context: http, server, location
You can specify several variables with this directive. If at least one of the variable is not empty and is not equal to '0', this substitution filter will be disabled.
Installation To install, get the source with subversion:
git clone git://github.com/yaoweibin/ngx_http_substitutions_filter_module.git
and then compile nginx with the following option:
./configure --add-module=/path/to/module
Known issue
Can't substitute the response header.
CHANGES Changes with nginx_substitutions_filter 0.6.4 2014-02-15
Now non-200 response will work
added the subs_filter_bypass directive
Changes with nginx_substitutions_filter 0.6.2 2012-08-26
fixed a bug of buffer overlap
fixed a bug with last zero buffer
Changes with nginx_substitutions_filter 0.6.0 2012-06-30
refactor this module
Changes with nginx_substitutions_filter 0.5.2 2010-08-11
do many optimizing for this module
fix a bug of buffer overlap
fix a segment fault bug when output chain return NGX_AGAIN.
fix a bug about last buffer with no linefeed. This may cause segment fault. Thanks for Josef Fröhle
Changes with nginx_substitutions_filter 0.5 2010-04-15
refactor the source structure, create branches of dev
fix a bug of small chunk of buffers causing lose content
fix the bug of last_buf and the nginx's compatibility above 0.8.25
fix a bug with unwanted capture config error in fix string substitution
add feature of regex captures
Changes with nginx_substitutions_filter 0.4 2009-12-23
fix many bugs
Changes with nginx_substitutions_filter 0.3 2009-02-04
Initial public release
Reporting a bug Questions/patches may be directed to Weibin Yao, yaoweibin@gmail.com.
Copyright & License This module is licensed under the BSD license.
Copyright (C) 2014 by Weibin Yao yaoweibin@gmail.com.
All rights reserved.
Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.