=encoding utf-8

=head1 NAME

ngx_http_spdy_module - Module ngx_http_spdy_module




=head1



The C<ngx_http_spdy_module> module provides experimental
support for L<SPDY|http://www.chromium.org/spdy/spdy-protocol>.
Currently,
L<draft
3.1|http://www.chromium.org/spdy/spdy-protocol/spdy-protocol-draft3-1> of SPDY protocol is implemented.

B<NOTE>

Before version 1.5.10,
L<draft
2|http://www.chromium.org/spdy/spdy-protocol/spdy-protocol-draft2> of SPDY protocol was implemented.






This module is not built by default, it should be enabled with
the C<--with-http_spdy_module>
configuration parameter.






B<NOTE>

This module was superseded by the
L<ngx_http_v2_module|ngx_http_v2_module> module
in 1.9.5.





=head1 Known Issues



The module is experimental, caveat emptor applies.





Current implementation of SPDY protocol does not support “server push”.





In versions prior to 1.5.9, responses in SPDY connections could not be
L<rate limited|ngx_http_core_module>.





Buffering of a client request body cannot be disabled
regardless of
L<ngx_http_proxy_module>,
L<ngx_http_fastcgi_module>,
L<ngx_http_uwsgi_module>, and
L<ngx_http_scgi_module>
directive values.




=head1 Example Configuration




    
    server {
        listen 443 ssl spdy;
    
        ssl_certificate server.crt;
        ssl_certificate_key server.key;
        ...
    }



B<NOTE>

Note that in order to accept both
L<HTTPS|ngx_http_ssl_module> and SPDY connections
simultaneously on the same port,
L<OpenSSL|http://www.openssl.org> library used should support
“Next Protocol Negotiation” TLS extension, available since OpenSSL
version 1.0.1.





=head1 Directives

=head2 spdy_chunk_size


B<syntax:> spdy_chunk_size I<I<C<size>>>


B<default:> I<8k>


B<context:> I<http>


B<context:> I<server>


B<context:> I<location>



This directive appeared in version 1.5.9.





Sets the maximum size of chunks
into which the response body is
L<sliced|http://www.chromium.org/spdy/spdy-protocol/spdy-protocol-draft2#TOC-Data-frames>.
A too low value results in higher overhead.
A too high value impairs prioritization due to
L<HOL blocking|http://en.wikipedia.org/wiki/Head-of-line_blocking>.







=head2 spdy_headers_comp


B<syntax:> spdy_headers_comp I<I<C<level>>>


B<default:> I<0>


B<context:> I<http>


B<context:> I<server>





Sets the header compression I<C<level>> of a response in a range from
1 (fastest, less compression) to 9 (slowest, best compression).
The special value 0 turns off the header compression.







=head1 Embedded Variables



The C<ngx_http_spdy_module> module
supports the following embedded variables:

=over



=item C<$spdy>




SPDY protocol version for SPDY connections,
or an empty string otherwise;



=item C<$spdy_request_priority>





request priority for SPDY connections,
or an empty string otherwise.




=back