How to handle gziped capture?

[robert-martens]

This may be more of a question than an issue. I want to feed the body of one capture into another ex:
local res2 = ngx.location.capture("/cap2?"..res1.body)
However res1.body was gziped by the origin server. Any idea how I can prevent the gzip of the body (a special Accept-Encoding header maybe) or unzip it using something like the gzio library on luaforge (http://luaforge.net/projects/gzio/)?

[chaoslawful]

Remove Accept-Encoding header from the request can prevent server responsing with gzip compressed content. If this can't be done, you can also decompress gzip'd content in Lua by using birmworks' lua-zlib module or similar ones (https://github.com/brimworks/lua-zlib).

[agentzh]

If you're using the ngx_proxy module for your subrequests, try using the following directive to prevent forwarding your original request's headers:

proxy_pass_request_headers off;

See http://wiki.nginx.org/NginxHttpProxyModule#proxy_pass_request_headers for more details.

Alternatively, you can explicitly remove the Accep-Encoding header in your subrequest location like this:

 more_clear_input_headers Accept-Encoding;

You need the ngx_headers_more module though. See http://wiki.nginx.org/NginxHttpHeadersMoreModule#more_clear_input_headers for more details :)

[robert-martens]

Thank-you. All three options work.

OPTION ONE

Placed:
more_clear_input_headers Accept-Encoding;
in "location /cap2"

OPTION TWO

Placed:
proxy_pass_request_headers off;
in "location /cap2"

OPTION THREE

Downloaded https://github.com/brimworks/lua-zlib :
make linux
cp zlib.so /usr/lib/lua/5.1/zlib.so

added following to conf:
local zlib = require("zlib")
local stream = zlib.inflate()
local inflated_body = stream(res1.body)
local res2 = ngx.location.capture("/cap2?"..inflated_body)

I like having all three as options (may need gz some time and good to be able to modify the headers). I also like the work that both of you are doing; very cool.

[shann09]

zzlib may help