From 1ba65539c6e39772e752dedf513df8ee83680858 Mon Sep 17 00:00:00 2001
From: JimMoen <LnJimMoen@outlook.com>
Date: Thu, 25 May 2023 15:28:56 +0800
Subject: [PATCH] chore: refine traces command usage

---
 apps/emqx_management/src/emqx_mgmt_cli.erl | 19 +++++++++++++------
 1 file changed, 13 insertions(+), 6 deletions(-)

diff --git a/apps/emqx_management/src/emqx_mgmt_cli.erl b/apps/emqx_management/src/emqx_mgmt_cli.erl
index 05ea5e4cf..27de11d0f 100644
--- a/apps/emqx_management/src/emqx_mgmt_cli.erl
+++ b/apps/emqx_management/src/emqx_mgmt_cli.erl
@@ -514,6 +514,8 @@ trace_off(Type, Filter) ->
 
 %%--------------------------------------------------------------------
 %% @doc Trace Cluster Command
+-define(DEFAULT_TRACE_DURATION, "1800").
+
 traces(["list"]) ->
     {200, List} = emqx_mgmt_api_trace:trace(get, []),
     case List of
@@ -542,7 +544,7 @@ traces(["stop", Name]) ->
 traces(["delete", Name]) ->
     trace_cluster_del(Name);
 traces(["start", Name, Operation, Filter]) ->
-    traces(["start", Name, Operation, Filter, "1800"]);
+    traces(["start", Name, Operation, Filter, ?DEFAULT_TRACE_DURATION]);
 traces(["start", Name, Operation, Filter0, DurationS]) ->
     case trace_type(Operation, Filter0) of
         {ok, Type, Filter} -> trace_cluster_on(Name, Type, Filter, DurationS);
@@ -551,11 +553,16 @@ traces(["start", Name, Operation, Filter0, DurationS]) ->
 traces(_) ->
     emqx_ctl:usage([
         {"traces list", "List all cluster traces started"},
-        {"traces start <Name> client <ClientId>", "Traces for a client in cluster"},
-        {"traces start <Name> topic <Topic>", "Traces for a topic in cluster"},
-        {"traces start <Name> ip_address <IPAddr>", "Traces for a IP in cluster"},
-        {"traces stop  <Name>", "Stop trace in cluster"},
-        {"traces delete  <Name>", "Delete trace in cluster"}
+        {"traces start <Name> client <ClientId> [<Duration>]", "Traces for a client in cluster"},
+        {"traces start <Name> topic <Topic> [<Duration>]", "Traces for a topic in cluster"},
+        {"traces start <Name> ip_address <IPAddr> [<Duration>]",
+            "Traces for a client IP in cluster\n"
+            "Trace will start immediately on all nodes, including the core and replicant,\n"
+            "and will end after <Duration> seconds. The default value for <Duration> is "
+            ?DEFAULT_TRACE_DURATION
+            " seconds."},
+        {"traces stop <Name>", "Stop trace in cluster"},
+        {"traces delete <Name>", "Delete trace in cluster"}
     ]).
 
 trace_cluster_on(Name, Type, Filter, DurationS0) ->