From c46aa151af89c8e6a3e3fca9a36c984c93ca06f4 Mon Sep 17 00:00:00 2001
From: ttt161 <losto@nix>
Date: Mon, 24 Aug 2026 10:45:38 +0300
Subject: [PATCH] add metrics for woody wrappers

---
 apps/ff_server/src/ff_server.erl              |  9 ++++++++-
 apps/ff_server/src/ff_woody_wrapper.erl       | 19 ++++++++++++------
 apps/hellgate/src/hellgate.erl                |  9 ++++++++-
 .../hg_proto/src/hg_woody_service_wrapper.erl | 20 ++++++++++++-------
 4 files changed, 42 insertions(+), 15 deletions(-)

diff --git a/apps/ff_server/src/ff_server.erl b/apps/ff_server/src/ff_server.erl
index a92fe25d..32e4e09a 100644
--- a/apps/ff_server/src/ff_server.erl
+++ b/apps/ff_server/src/ff_server.erl
@@ -131,4 +131,11 @@ wrap_handler(Handler, WrapperOpts) ->
 
 setup_metrics() ->
     ok = woody_ranch_prometheus_collector:setup(),
-    ok = woody_hackney_prometheus_collector:setup().
+    ok = woody_hackney_prometheus_collector:setup(),
+    _ = prometheus_histogram:declare([
+        {name, woody_wrapper_processing_duration_ms},
+        {help, "Duration of processing handle_function in millisecond"},
+        {buckets, [50, 150, 300, 500, 750, 1000]},
+        {labels, [handler, function]}
+    ]),
+    ok.
diff --git a/apps/ff_server/src/ff_woody_wrapper.erl b/apps/ff_server/src/ff_woody_wrapper.erl
index a6c47de0..3e77e6eb 100644
--- a/apps/ff_server/src/ff_woody_wrapper.erl
+++ b/apps/ff_server/src/ff_woody_wrapper.erl
@@ -37,12 +37,19 @@ handle_function(Func, Args, WoodyContext0, #{handler := Handler} = Opts) ->
     WoodyContext = ensure_woody_deadline_set(WoodyContext0, Opts),
     {HandlerMod, HandlerOptions} = get_handler_opts(Handler),
     ok = op_context:save(op_context:key(fistful), create_context(WoodyContext, Opts)),
-    try
-        HandlerMod:handle_function(
-            Func,
-            Args,
-            HandlerOptions
-        )
+    F = fun() -> HandlerMod:handle_function(Func, Args, HandlerOptions) end,
+    try timer:tc(F) of
+        {DurationMicro, Result} ->
+            DurationMs = DurationMicro div 1000,
+            HandlerBin = erlang:atom_to_binary(HandlerMod),
+            FuncBin = erlang:atom_to_binary(Func),
+            Labels = [HandlerBin, FuncBin],
+            ok = prometheus_histogram:observe(
+                woody_wrapper_processing_duration_ms,
+                Labels,
+                DurationMs
+            ),
+            Result
     after
         op_context:cleanup(fistful)
     end.
diff --git a/apps/hellgate/src/hellgate.erl b/apps/hellgate/src/hellgate.erl
index 64d934da..19df3675 100644
--- a/apps/hellgate/src/hellgate.erl
+++ b/apps/hellgate/src/hellgate.erl
@@ -111,4 +111,11 @@ stop(_State) ->
 
 setup_metrics() ->
     ok = woody_ranch_prometheus_collector:setup(),
-    ok = woody_hackney_prometheus_collector:setup().
+    ok = woody_hackney_prometheus_collector:setup(),
+    _ = prometheus_histogram:declare([
+        {name, woody_wrapper_processing_duration_ms},
+        {help, "Duration of processing handle_function in millisecond"},
+        {buckets, [50, 150, 300, 500, 750, 1000]},
+        {labels, [handler, function]}
+    ]),
+    ok.
diff --git a/apps/hg_proto/src/hg_woody_service_wrapper.erl b/apps/hg_proto/src/hg_woody_service_wrapper.erl
index 761bc1b8..613cb000 100644
--- a/apps/hg_proto/src/hg_woody_service_wrapper.erl
+++ b/apps/hg_proto/src/hg_woody_service_wrapper.erl
@@ -33,13 +33,19 @@
 handle_function(Func, Args, WoodyContext0, #{handler := Handler} = Opts) ->
     WoodyContext = ensure_woody_deadline_set(WoodyContext0, Opts),
     ok = op_context:save(op_context:key(hellgate), create_context(WoodyContext, Opts)),
-    try
-        Result = Handler:handle_function(
-            Func,
-            Args,
-            Opts
-        ),
-        {ok, Result}
+    F = fun() -> Handler:handle_function(Func, Args, Opts) end,
+    try timer:tc(F) of
+        {DurationMicro, Result} ->
+            DurationMs = DurationMicro div 1000,
+            HandlerBin = erlang:atom_to_binary(Handler),
+            FuncBin = erlang:atom_to_binary(Func),
+            Labels = [HandlerBin, FuncBin],
+            ok = prometheus_histogram:observe(
+                woody_wrapper_processing_duration_ms,
+                Labels,
+                DurationMs
+            ),
+            {ok, Result}
     catch
         throw:Reason ->
             raise(Reason)