diff options
| -rw-r--r-- | src/rabbit_peer_discovery_dns.erl | 75 |
1 files changed, 75 insertions, 0 deletions
diff --git a/src/rabbit_peer_discovery_dns.erl b/src/rabbit_peer_discovery_dns.erl new file mode 100644 index 0000000000..5f20b66016 --- /dev/null +++ b/src/rabbit_peer_discovery_dns.erl @@ -0,0 +1,75 @@ +%% The contents of this file are subject to the Mozilla Public License +%% Version 1.1 (the "License"); you may not use this file except in +%% compliance with the License. You may obtain a copy of the License at +%% http://www.mozilla.org/MPL/ +%% +%% Software distributed under the License is distributed on an "AS IS" +%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See the +%% License for the specific language governing rights and limitations +%% under the License. +%% +%% The Original Code is RabbitMQ. +%% +%% The Initial Developer of the Original Code is GoPivotal, Inc. +%% Copyright (c) 2007-2016 Pivotal Software, Inc. All rights reserved. +%% + +-module(rabbit_peer_discovery_dns). +-behaviour(rabbit_peer_discovery_backend). + +-include("rabbit.hrl"). + +-export([list_nodes/0, register/0, unregister/0]). +-export([discover_nodes/2]). + +%% +%% API +%% + +-spec list_nodes() -> {ok, Nodes :: list()} | {error, Reason :: string()}. + +list_nodes() -> + case application:get_env(rabbit, autocluster) of + undefined -> io:format("rabbit.autocluster~n", []), {[], disc}; + {ok, Autocluster} -> + case proplists:get_value(peer_discovery_dns, Autocluster) of + undefined -> io:format("rabbit.autocluster.peer_discovery_dns~n", []), {[], disc}; + Proplist -> + Hostname = rabbit_data_coercion:to_list(proplists:get_value(hostname, Proplist)), + NodeType = proplists:get_value(node_type, Autocluster, disc), + + {discover_nodes(Hostname, net_kernel:longnames()), NodeType} + end + end. + +-spec register() -> ok. + +register() -> + ok. + +-spec unregister() -> ok. + +unregister() -> + ok. + + +%% +%% Implementation +%% + +discover_nodes(SeedHostname, LongNamesUsed) -> + discover_hostnames(SeedHostname, LongNamesUsed). + +discover_hostnames(SeedHostname, LongNamesUsed) -> + Hosts = [extract_host(inet_res:gethostbyaddr(A), LongNamesUsed) || A <- inet_res:lookup(SeedHostname, in, a)], + lists:filter(fun(E) -> E =/= error end, Hosts). + +%% long node names are used +extract_host({ok, {hostent, FQDN, _, _, _, _}}, true) -> + FQDN; +%% short node names are used +extract_host({ok, {hostent, FQDN, _, _, _, _}}, false) -> + lists:nth(1, string:tokens(FQDN, ".")); +extract_host(Error, _) -> + rabbit_log:error("DNS peer discovery failed: ~p", [Error]), + error. |