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-module(erlbal).
-export([make_request/0, start_bal/0, kill_bal/0, start_server/1]).
start_server(ID) ->
PID = spawn(fun() -> serverloop(ID) end),
balancer ! {add_node, PID}.
serverloop(ID) ->
receive
{request, From} ->
balancer ! {response, From, ID},
serverloop(ID);
die ->
ok
end.
start_bal() ->
register(balancer, spawn(fun() -> balloop([], 1) end)).
kill_bal() ->
balancer ! die.
balloop(Serverlist, Nextserver) ->
receive
{add_node, PID} ->
balloop(Serverlist ++ [PID], Nextserver);
{request, From} ->
Serv = lists:nth(Nextserver, Serverlist),
Serv ! {request, From},
NS = Nextserver + 1,
SLL = length(Serverlist),
if
NS > SLL ->
balloop(Serverlist, 1);
true ->
balloop(Serverlist, Nextserver+1)
end;
{response, To, ID} ->
To ! ID,
balloop(Serverlist, Nextserver);
die ->
lists:foreach(fun(X) -> X ! die end, Serverlist)
end.
make_request() ->
balancer ! {request, self()},
receive
ID ->
ID
end.
|
