From 7d9ad960219a95a63f7f9b1b7d3041c1d1923ff1 Mon Sep 17 00:00:00 2001
From: Feng <ery.lee@gmail.com>
Date: Fri, 9 Sep 2016 22:52:17 +0800
Subject: [PATCH] refactor emqttd_conf

---
 src/emqttd.erl      |  6 +++---
 src/emqttd_app.erl  |  2 +-
 src/emqttd_conf.erl | 52 +++++++++++++++++++++++++--------------------
 3 files changed, 33 insertions(+), 27 deletions(-)

diff --git a/src/emqttd.erl b/src/emqttd.erl
index e57b56e0d..5221969de 100644
--- a/src/emqttd.erl
+++ b/src/emqttd.erl
@@ -53,7 +53,7 @@
 -define(APP, ?MODULE).
 
 %%--------------------------------------------------------------------
-%% Bootstrap, environment, is_running...
+%% Bootstrap, environment, configuration, is_running...
 %%--------------------------------------------------------------------
 
 %% @doc Start emqttd application.
@@ -62,10 +62,10 @@ start() -> application:start(?APP).
 
 %% @doc Get Config
 -spec(conf(Key :: atom()) -> any()).
-conf(Key) -> gen_conf:value(?APP, Key).
+conf(Key) -> emqttd_conf:value(Key).
 
 -spec(conf(Key :: atom(), Default :: any()) -> any()).
-conf(Key, Default) -> gen_conf:value(?APP, Key, Default).
+conf(Key, Default) -> emqttd_conf:value(Key, Default).
 
 %% @doc Environment
 -spec(env(Key:: atom()) -> any()).
diff --git a/src/emqttd_app.erl b/src/emqttd_app.erl
index 65af78ec3..81f1d329c 100644
--- a/src/emqttd_app.erl
+++ b/src/emqttd_app.erl
@@ -42,7 +42,7 @@
       Reason    :: term()).
 start(_StartType, _StartArgs) ->
     print_banner(),
-    gen_conf:init(emqttd),
+    emqttd_conf:init(),
     emqttd_mnesia:start(),
     {ok, Sup} = emqttd_sup:start_link(),
     start_servers(Sup),
diff --git a/src/emqttd_conf.erl b/src/emqttd_conf.erl
index 5836f93a4..b3677d6b4 100644
--- a/src/emqttd_conf.erl
+++ b/src/emqttd_conf.erl
@@ -16,83 +16,90 @@
 
 -module(emqttd_conf).
 
--import(gen_conf, [value/3]).
+-export([init/0]).
 
 -export([mqtt/0, session/0, queue/0, bridge/0, pubsub/0]).
 
--export([list/1]).
+-export([value/1, value/2, list/1]).
 
 -define(APP, emqttd).
 
+init() -> gen_conf:init(?APP).
+
 mqtt() ->
     with_env(mqtt_protocol, [
         %% Max ClientId Length Allowed.
-        {max_clientid_len,    value(?APP, mqtt_max_clientid_len, 512)},
+        {max_clientid_len,    value(mqtt_max_clientid_len, 512)},
         %% Max Packet Size Allowed, 64K by default.
-        {max_packet_size,     value(?APP, mqtt_max_packet_size, 65536)},
+        {max_packet_size,     value(mqtt_max_packet_size, 65536)},
         %% Client Idle Timeout.
-        {client_idle_timeout, value(?APP, mqtt_client_idle_timeout, 30)}
+        {client_idle_timeout, value(mqtt_client_idle_timeout, 30)}
     ]).
 
 session() ->
     with_env(mqtt_session, [
         %% Max number of QoS 1 and 2 messages that can be “inflight” at one time.
         %% 0 means no limit
-        {max_inflight,         value(?APP, session_max_inflight, 100)},
+        {max_inflight,         value(session_max_inflight, 100)},
 
         %% Retry interval for redelivering QoS1/2 messages.
-        {unack_retry_interval, value(?APP, session_unack_retry_interval, 60)},
+        {unack_retry_interval, value(session_unack_retry_interval, 60)},
 
         %% Awaiting PUBREL Timeout
-        {await_rel_timeout,    value(?APP, session_await_rel_timeout, 20)},
+        {await_rel_timeout,    value(session_await_rel_timeout, 20)},
 
         %% Max Packets that Awaiting PUBREL, 0 means no limit
-        {max_awaiting_rel,     value(?APP, session_max_awaiting_rel, 0)},
+        {max_awaiting_rel,     value(session_max_awaiting_rel, 0)},
 
         %% Statistics Collection Interval(seconds)
-        {collect_interval,     value(?APP, session_collect_interval, 0)},
+        {collect_interval,     value(session_collect_interval, 0)},
 
         %% Expired after 2 day (unit: minute)
-        {expired_after,        value(?APP, session_expired_after, 2880)}
+        {expired_after,        value(session_expired_after, 2880)}
     ]).
 
 queue() ->
     with_env(mqtt_queue, [
         %% Type: simple | priority
-        {type, value(?APP, queue_type, simple)},
+        {type,             value(queue_type, simple)},
 
         %% Topic Priority: 0~255, Default is 0
-        {priority, value(?APP, queue_priority, [])},
+        {priority,         value(queue_priority, [])},
 
         %% Max queue length. Enqueued messages when persistent client disconnected,
         %% or inflight window is full.
-        {max_length, value(?APP, queue_max_length, infinity)},
+        {max_length,       value(queue_max_length, infinity)},
 
         %% Low-water mark of queued messages
-        {low_watermark, value(?APP, queue_low_watermark, 0.2)},
+        {low_watermark,    value(queue_low_watermark, 0.2)},
 
         %% High-water mark of queued messages
-        {high_watermark, value(?APP, queue_high_watermark, 0.6)},
+        {high_watermark,   value(queue_high_watermark, 0.6)},
 
         %% Queue Qos0 messages?
-        {queue_qos0, value(?APP, queue_qos0, true)}
+        {queue_qos0,       value(queue_qos0, true)}
     ]).
 
 bridge() ->
     with_env(mqtt_bridge, [
-        %% TODO: Bridge Queue Size
-        {max_queue_len,      value(?APP, bridge_max_queue_len, 10000)},
+        {max_queue_len,      value(bridge_max_queue_len, 10000)},
 
         %% Ping Interval of bridge node
-        {ping_down_interval, value(?APP, bridge_ping_down_interval, 1)}
+        {ping_down_interval, value(bridge_ping_down_interval, 1)}
     ]).
 
 pubsub() ->
     with_env(mqtt_pubsub, [
         %% PubSub and Router. Default should be scheduler numbers.
-        {pool_size, value(?APP, pubsub_pool_size, 8)}
+        {pool_size, value(pubsub_pool_size, 8)}
     ]).
 
+value(Key) ->
+    with_env(Key, gen_conf:value(?APP, Key)).
+
+value(Key, Default) ->
+    with_env(Key, gen_conf:value(?APP, Key, Default)).
+
 with_env(Key, Conf) ->
     case application:get_env(?APP, Key) of
         undefined ->
@@ -101,6 +108,5 @@ with_env(Key, Conf) ->
             Val
     end.
 
-list(Key) ->
-    gen_conf:list(?APP, Key).
+list(Key) -> gen_conf:list(?APP, Key).