Today, on a whim, I released a module called HTTP::Request::AsCurl to CPAN. It converts an HTTP::Request object to a curl command.

use HTTP::Request::Common;
use HTTP::Request::AsCurl;

my $request = POST('api.earth.defense/weapon1', { 
    target => 'mothership', 
    when   => 'now' 
});

say join "\n", $request->as_curl;
# curl --dump-header - -XPOST "api.earth.defense/weapon1" \
# --data 'target=mothership' \
# --data 'when=now'

It works by injecting the as_curl() method into the HTTP::Request namespace. This must be a bad idea and probably not a great bit of code to rely on in a production environment. But it is pretty convenient syntax for debugging a REST API and I couldn’t resist. Thoughts, suggestions, criticism?

– UPDATE (2014-06-01) –

I released a new version which has a totally different user interface. Here is the new synopsis:

use HTTP::Request::Common;
use HTTP::Request::AsCurl qw/as_curl/;

my $request = POST('api.earth.defense/weapon1', { 
    target => 'mothership', 
    when   => 'now' 
});

system as_curl($request);

print as_curl($request, pretty => 1, newline => "\n", shell => 'bourne');
# curl \
# --request POST api.earth.defense/weapon1 \
# --dump-header - \
# --data target=mothership \
# --data when=now

There are 2 major changes.

1. I’m no longer doing namespace injection. I really liked the syntax, but it was problematic and unnecessary.
2. The old version returned a formatted array of strings which was not very useful. The problem with a formatted string (as was helpfully pointed out to me) is you have worry about stuff like newlines which depends on the system you are targeting and shell escaping which depends on the shell you are targeting. This is a can of worms. Hopefully this new interface is an improvement.