%%
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 2003-2016. All Rights Reserved.
%%
%% Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
%%
%% Unless required by applicable law or agreed to in writing, software
%% distributed under the License is distributed on an "AS IS" BASIS,
%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
%% See the License for the specific language governing permissions and
%% limitations under the License.
%%
%% %CopyrightEnd%
%%
-module(snmp_app).
-behaviour(application).
-include("snmp_debug.hrl").
%%%-----------------------------------------------------------------
%%% This module implements the SNMP application.
%%%-----------------------------------------------------------------
-export([start/2, stop/0, stop/1, config_change/3]).
-export([start_agent/0, start_agent/1, start_agent/2]).
-export([start_manager/0, start_manager/1, start_manager/2]).
start(Type, []) ->
?d("start -> entry with"
"~n Type. ~p", [Type]),
%% This is the new snmp application config format
%% First start the (new) central supervisor,
{ok, Pid} = snmp_app_sup:start_link(),
Entities = entities(),
ok = start_entities(Type, Entities),
{ok, Pid}.
entities() ->
entities([agent, manager], []).
entities([], []) ->
?d("entities -> entry when no entities", []),
%% Could be old style snmp (agent) application config format
%% but could also be a skeleton start, which means that neither
%% agent nor manager config has been specified
case get_env() of
[] ->
%% Skeleton start
?d("entities -> skeleton start", []),
[];
OldConf when is_list(OldConf) ->
?d("entities -> old style config: ~n~p", [OldConf]),
%% Old style snmp (agent) application config format
Conf = snmpa_app:convert_config(OldConf),
?d("entities -> converted config: ~n~p", [Conf]),
[{agent, Conf}]
end;
entities([], Acc) ->
?d("entities -> done", []),
lists:reverse(Acc);
entities([Ent|Ents], Acc) ->
?d("entities -> entry with"
"~n Ent: ~p", [Ent]),
case application:get_env(snmp, Ent) of
{ok, Conf} ->
entities(Ents, [{Ent, Conf}|Acc]);
_ ->
entities(Ents, Acc)
end.
start_entities(_Type, []) ->
ok;
start_entities(Type, [{agent, Opts}|Entities]) ->
case start_agent(Type, Opts) of
ok ->
start_entities(Type, Entities);
Error ->
Error
end;
start_entities(Type, [{manager, Opts}|Entities]) ->
case start_manager(Type, Opts) of
ok ->
start_entities(Type, Entities);
Error ->
Error
end;
start_entities(Type, [BadEntity|Entities]) ->
error_msg("Bad snmp configuration: ~n: ~p", [BadEntity]),
start_entities(Type, Entities).
start_agent() ->
start_agent(normal).
start_agent(Type) when is_atom(Type) ->
case application:get_env(snmp, agent) of
{ok, Opts} ->
start_agent(Type, Opts);
_ ->
{error, missing_config}
end;
start_agent(Opts) when is_list(Opts) ->
start_agent(normal, Opts);
start_agent(BadArg) ->
{error, {bad_arg, BadArg}}.
start_agent(Type, Opts) ->
?d("start_agent -> entry", []),
case snmp_app_sup:start_agent(Type, Opts) of
{ok, _} ->
ok;
Error ->
Error
end.
start_manager() ->
start_manager(normal).
start_manager(Type) when is_atom(Type) ->
case application:get_env(snmp, manager) of
{ok, Opts} ->
start_manager(Type, Opts);
_ ->
{error, missing_config}
end;
start_manager(Opts) when is_list(Opts) ->
start_manager(normal, Opts);
start_manager(BadArg) ->
{error, {bad_arg, BadArg}}.
start_manager(Type, Opts) ->
?d("start manager -> entry", []),
case snmp_app_sup:start_manager(Type, Opts) of
{ok, _} ->
ok;
Error ->
Error
end.
stop(_) ->
ok.
stop() ->
snmp_app_sup:stop().
get_env() ->
Env = application:get_all_env(snmp),
DeleteElem = [included_applications],
F = fun({Key, _}) -> lists:member(Key, DeleteElem) end,
lists:dropwhile(F, Env).
%%-----------------------------------------------------------------
%% The presence of this function means that we will accept changes
%% in the configuration parameters. However, we won't react upon
%% those changes until the app is restarted. So we just return
%% ok.
%%-----------------------------------------------------------------
config_change(_Changed, _New, _Removed) ->
ok.
%% ---------------------------------------------------------------------
error_msg(F, A) ->
error_logger:error_msg("~w: " ++ F ++ "~n", [?MODULE|A]).
