[erlang-questions] upnp device discovery

[Alexander Harju]

> Has anybody got some erlang code for upnp device disovery?
>
> /Joe
>

Hi.
I was just experimenting with last weekend.

For discovery you just have to send the discovery message to multicast
address 239.255.255.250:1900

-define(UPNP_DISCOVER,
    "M-SEARCH * HTTP/1.1\r\n"
    "Host: 239.255.255.250:1900\r\n"
    "Man: \"ssdp:discover\"\r\n"
    "ST: upnp:rootdevice\r\n"
    "MX: 3\r\n\r\n").


{ok, S} = gen_udp:open(1900, [{reuseaddr,true}]),

gen_udp:send(S, {239,255,255,250}, 1900, ?UPNP_DISCOVER),
receive
    {udp, S, _, _, Msg0} ->
        [_|Msg] = lists:reverse(Msg0),
        io:format("~s~n", [lists:reverse(Msg)])
    after 5000 ->
           ok
end.

The rest is "just" handling the UPnP massive SOAP protocol. xmerl and inets
or yaws, erlsom.


You can also listen to UPnP multicasts like this:

Opts = [{multicast_loop,false},
              {multicast_if,{0,0,0,0}},
              {multicast_ttl,4}],

{ok, S} = gen_udp**:open(1900, Opts),
inet:setopts(S, [{add_membership, {Ip, {0,0,0,0}}}]),

receive
    {udp, S, ...

BR
// Alex