This vmod provides cURL bindings for Varnish so you can use Varnish
as an HTTP client and fetch headers and bodies from backends.

Usage:
./configure VARNISHSRC=DIR [VMODDIR=DIR]

VARNISHSRC is the directory of the Varnish source tree for which to
compile your vmod. Both the VARNISHSRC and VARNISHSRC/include
will be added to the include search paths for your module.

Optionally you can also set the vmod install directory by adding
VMODDIR=DIR (defaults to the pkg-config discovered directory from your
Varnish installation).

Make targets:
make - builds the vmod
make install - installs your vmod in VMODDIR
make check - runs the unit tests in src/tests/*.vtc

To use the vmod do something along the lines of:

import curl;

sub vcl_recv {
    curl.fetch("http://example.com/test");
    if (curl.header("X-Foo") == "bar") {
        …
    }
    curl.free();
}

See src/vmod_curl.vcc for the rest of the callable functions.

Development of this VMOD has been sponsored by the Norwegian company
Aspiro Music AS for usage on their WiMP music streaming service.