Erlang General Non-blocking TCP/SSL Socket Server.
- General Non-blocking TCP/SSL Socket Server
- Acceptor Pool and Asynchronous TCP Accept
- UDP/DTLS Server
- Max connections management
- Allow/Deny by peer address
- Proxy Protocol V1/V2
- Keepalive Support
- Rate Limit
- IPv6 Support
A Simple TCP Echo Server:
-module(echo_server). -export([start_link/2, init/2]). start_link(Transport, Sock) -> {ok, spawn_link(?MODULE, init, [Transport, Sock])}. init(Transport, Sock) -> case Transport:wait(Sock) of {ok, NewSock} -> loop(Transport, NewSock); Error -> Error end. loop(Transport, Sock) -> case Transport:recv(Sock, 0) of {ok, Data} -> {ok, Peername} = Transport:peername(Sock), Transport:send(Sock, Data), loop(Transport, Sock); {error, Reason} -> io:format("TCP Error: ~s~n", [Reason]), {stop, Reason} end. Setup Echo Server:
%% Start esockd application ok = esockd:start(). Options = [{acceptors, 10}, {max_connections, 1024}, {tcp_options, [binary, {reuseaddr, true}]}]. MFArgs = {echo_server, start_link, []}, esockd:open(echo, 5000, Options, MFArgs). | Example | Description |
|---|---|
| examples/async_recv | prim_net async recv/send |
| examples/gen_server | gen_server behaviour |
| examples/simple | simple echo server |
| examples/ssl | ssl echo server |
| examples/proxy_protocol | proxy protocol v1/2 |
| examples/udp | udp echo server |
| examples/dtls | dtls echo server |
esockd:open(echo, 5000, [{tcp_options, [binary, {reuseaddr, true}]}], {echo_server, start_link, []}). esockd:open(echo, {"127.0.0.1", 6000}, [{tcp_options, [binary, {reuseaddr, true}]}], {echo_server, start_link, []}). Spec:
-spec(open(Protocol, ListenOn, Options, MFArgs) -> {ok, pid()} | {error, term()} when Protocol :: atom(), ListenOn :: inet:port_number() | {host(), inet:port_number()}), Options :: [option()], MFArgs :: esockd:mfargs()). Option:
-type(option() :: {acceptors, pos_integer()} | {max_connections, pos_integer()} | {max_conn_rate, pos_integer()} | {access_rules, [esockd_access:rule()]} | {shutdown, brutal_kill | infinity | pos_integer()} | tune_buffer | {tune_buffer, boolean()} | proxy_protocol | {proxy_protocol, boolean()} | {proxy_protocol_timeout, timeout()} | {ssl_options, [ssl:ssl_option()]} | {udp_options, [gen_udp:option()]} | {dtls_options, [gen_udp:option() | ssl:ssl_option()]}). MFArgs:
-type(mfargs() :: atom() | {atom(), atom()} | {module(), atom(), [term()]}). Get stats:
esockd:get_stats({echo, 5000}). Get acceptors:
esockd:get_acceptors({echo, {"127.0.0.1", 6000}}). Get/Set max connections:
esockd:get_max_connections({echo, 5000}). esockd:set_max_connections({echo, 5000}, 100000). Same to Allow/Deny Syntax of nginx:
allow address | CIDR | all; deny address | CIDR | all; allow/deny by options:
esockd:open(echo, 5000, [{access, [{deny, "192.168.1.1"}, {allow, "192.168.1.0/24"}, {deny, all}]}], MFArgs). allow/deny by API:
esockd:allow({echo, 5000}, all). esockd:allow({echo, 5000}, "192.168.0.1/24"). esockd:deny({echo, 5000}, all). esockd:deny({echo, 5000}, "10.10.0.0/16"). esockd:close(echo, 5000). esockd:close(echo, {"127.0.0.1", 6000}). Spec:
-spec(close(Protocol, ListenOn) -> ok when Protocol :: atom(), ListenOn :: inet:port_number() | {host(), inet:port_number()}). Connecting to ssl_echo_server:
openssl s_client -connect 127.0.0.1:5000 -ssl3 openssl s_client -connect 127.0.0.1:5000 -tls1 esockd_sup -> esockd_listener_sup -> esockd_listener -> esockd_acceptor_sup -> esockd_acceptor -> esockd_acceptor -> ...... -> esockd_connection_sup -> esockd_connection -> esockd_connection -> ...... -
Acceptor Pool
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Suspend for one second when e{n, m}file errors happened
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Create a connection, and let it run...
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Control maximum connections
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Count active connections
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Count shutdown reasons
CIDR Wiki: https://en.wikipedia.org/wiki/Classless_Inter-Domain_Routing
Benchmark 2.1.0-alpha release on one 8 cores, 32G memory ubuntu/14.04 server::
250K concurrent connections, 50K messages/sec, 40Mbps In/Out consumed 5G memory, 20% CPU/core Apache License Version 2.0
EMQX Team.