GaoYusong/erlang-traffic-control

A traffic control library written in Erlang uses the token bucket algorithm to manage the rate of flow.

Erlang traffic control

A traffic control application written in erlang, you can use it to control the rate of flow, now it is implemented by using token buckets algorithm.

Notice

1. master branch is stable now, you can use it directly.
2. the project has been stable for two years running in our system
3. i wrote this project when i was an erlang learner, so the code style may be not good -:(

Two ways to use it

It can be used by block or non-block your application, and you can find demo in src/demo_worker.erl.

Block demo

start(Pid) ->
start(1000000, Pid).

start(N, Pid) ->
    spawn(fun() ->
        for(N, fun() -> tokens_queue:request_tokens(Pid) end)
    end).

for (0, _Func) ->
	ok;
for (N, Func) ->
	Func(),
	for (N - 1, Func).

Run block demo

{ok, Pid} = tokens_queue_manager:new_tokens_queue(100),
demo_worker:start(Pid).

%% show status
tokens_queue:infos(Pid).

Non-block demo

start_with_callback(Pid) ->
spawn(fun() ->
		Self = self(),
		tokens_queue:set_callback_function(Pid, fun() -> Self ! wakeup end),
		tokens_queue:request_tokens_cast(Pid),
		loop(Pid)
	end).

loop(Pid) ->
	receive
		wakeup ->
			tokens_queue:request_tokens_cast(Pid),
			loop(Pid);
		_Other ->
			io:format("I am fine!~n"),
			loop(Pid)
	end.

Run non-block demo

{ok, Pid} = tokens_queue_manager:new_tokens_queue(100),
UserPid = demo_worker:start_with_callback(Pid).

%% show status
tokens_queue:infos(Pid).

Unified MySQL Platform

This application is used in proxy module in Unified MySQL Platform from taobao to control sql query per second.

TODO

• Add a good tutorial.
• Add a lisence file, maybe BSD like license is good choice.