lhttpc_sup.erl

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%%% @author Oscar Hellström <oscar@hellstrom.st>
%%% @doc Top supervisor for the lhttpc application.
%%% This is normally started by the application behaviour implemented in
%%% {@link lhttpc}.
%%% @end
-module(lhttpc_sup).
-behaviour(supervisor).

-export([start_link/0, start_link/1]).
-export([init/1]).

-type child() :: {atom(), {atom(), atom(), list(any)},
    atom(), integer(), atom(), list(atom())}.

%% @spec () -> {ok, pid()} | {error, Reason}
%% Reason = atom()
%% @doc Starts and links to the supervisor.
%% This is normally called from an application behaviour or from another
%% supervisor.
%% @end
-spec start_link() -> {ok, pid()} | {error, atom()}.
start_link() ->
    supervisor:start_link({local, ?MODULE}, ?MODULE, []).

start_link(Args) ->
    supervisor:start_link({local, ?MODULE}, ?MODULE, Args).

%% @hidden
-spec init(any()) -> {ok, {{atom(), integer(), integer()}, [child()]}}.
init(Opts) ->
    init_ets(Opts),
    {ok, {{simple_one_for_one, 10, 1}, [
        {load_balancer,
         {lhttpc_lb, start_link, []},
         transient, 10000, worker, [lhttpc_lb]}
    ]}}.

init_ets(Opts) ->
    ETSOpts = proplists:get_value(ets, Opts, []),
    %% Only option supported so far -- others do not really make sense at this point
    ReadConc = {read_concurrency, proplists:get_value(read_concurrency, ETSOpts, false)},
    ets:new(lhttpc_lb, [named_table, set, public, ReadConc]).