chore(gw): more comment for coap options

apps/emqx_gateway/etc/emqx_gateway.conf

@@ -29,13 +29,11 @@ gateway.stomp {
     password = "${Packet.headers.passcode}"
   }
 
-  authentication: [
-      # {
-      #   name = "authenticator1"
-      #   type = "password-based:built-in-database"
-      #   user_id_type = clientid
-      #  }
-  ]
+  authentication: {
+    name = "authenticator1"
+    type = "password-based:built-in-database"
+    user_id_type = clientid
+  }
 
   listeners.tcp.default {
     bind = 61613
@@ -98,16 +96,55 @@ gateway.coap {
   ## When publishing or subscribing, prefix all topics with a mountpoint string.
   mountpoint = ""
 
-  notify_type = qos
+  ## Enable or disable connection mode
+  ## If true, you need to establish a connection before send any publish/subscribe
+  ## requests
+  ##
+  ## Default: false
+  #connection_required = false
 
-  ## if true, you need to establish a connection before use
-  connection_required = false
-  subscribe_qos = qos0
-  publish_qos = qos1
+  ## The Notification Message Type.
+  ## The notification message will be delivered to the CoAP client if a new
+  ## message received on an observed topic.
+  ## The type of delivered coap message can be set to:
+  ##  - non: Non-confirmable
+  ##  - con: Confirmable
+  ##  - qos: Mapping from QoS type of the recevied message.
+  ##         QoS0 -> non,  QoS1,2 -> con.
+  ##
+  ## Enum: non | con | qos
+  ## Default: qos
+  #notify_type = qos
+
+  ## The *Default QoS Level* indicator for subscribe request.
+  ## This option specifies the QoS level for the CoAP Client when establishing
+  ## a subscription membership, if the subscribe request is not carried `qos`
+  ## option.
+  ## The indicator can be set to:
+  ##  - qos0, qos1, qos2: Fixed default QoS level
+  ##  - coap: Dynamic QoS level by the message type of subscribe request
+  ##    * qos0: If the subscribe request is non-confirmable
+  ##    * qos1: If the subscribe request is confirmable
+  ##
+  ## Enum: qos0 | qos1 | qos2 | coap
+  ## Default: coap
+  #subscribe_qos = coap
+
+  ## The *Default QoS Level* indicator for publish request.
+  ## This option specifies the QoS level for the CoAP Client when publishing a
+  ## message to EMQ X PUB/SUB system, if the publish request is not carried `qos`
+  ## option.
+  ## The indicator can be set to:
+  ## - qos0, qos1, qos2: Fixed default QoS level
+  ## - coap: Dynamic QoS level by the message type of publish request
+  ##    * qos0: If the publish request is non-confirmable
+  ##    * qos1: If the publish request is confirmable
+  ##
+  ## Enum: qos0 | qos1 | qos2 | coap
+  #publish_qos = coap
 
   listeners.udp.default {
     bind = 5683
-    acceptors = 4
     max_connections = 102400
     max_conn_rate = 1000
 
@@ -133,6 +170,7 @@ gateway.coap {
     dtls.keyfile = "{{ platform_etc_dir }}/certs/key.pem"
     dtls.certfile = "{{ platform_etc_dir }}/certs/cert.pem"
     dtls.cacertfile = "{{ platform_etc_dir }}/certs/cacert.pem"
+    dtls.handshake_timeout = 15s
   }
 }
 
@@ -219,9 +257,14 @@ gateway.lwm2m {
 
   xml_dir = "{{ platform_etc_dir }}/lwm2m_xml"
 
+  ##
+  ##
   lifetime_min = 1s
+
   lifetime_max = 86400s
-  qmode_time_windonw = 22
+
+  qmode_time_window = 22
+
   auto_observe = false
 
   ## always | contains_object_list