fix self_trace by just relying on Trace_provider

src/client-cohttp-eio/opentelemetry_client_cohttp_eio.ml

@@ -185,7 +185,8 @@ let setup_ ~sw ~config env : unit =
     config.log_level;
 
   Opentelemetry.Self_debug.log Opentelemetry.Self_debug.Info (fun () ->
-      "opentelemetry: cohttp-eio exporter installed")
+      "opentelemetry: cohttp-eio exporter installed");
+  Opentelemetry_client.Self_trace.set_enabled config.self_trace
 
 let setup ?(config = Config.make ()) ?(enable = true) ~sw env =
   if enable && not config.sdk_disabled then setup_ ~sw ~config env

src/client-cohttp-lwt/opentelemetry_client_cohttp_lwt.ml

@@ -119,7 +119,7 @@ let setup_ ~config () : unit =
 
   Opentelemetry.Self_debug.log Opentelemetry.Self_debug.Info (fun () ->
       "opentelemetry: cohttp-lwt exporter installed");
-
+  Opentelemetry_client.Self_trace.set_enabled config.self_trace;
   ()
 
 let setup ?(config = Config.make ()) ?(enable = true) () =

src/client-ocurl-lwt/opentelemetry_client_ocurl_lwt.ml

@@ -94,6 +94,7 @@ let setup_ ~config () : Exporter.t =
 
   Opentelemetry.Self_debug.log Opentelemetry.Self_debug.Info (fun () ->
       "opentelemetry: ocurl-lwt exporter installed");
+  Opentelemetry_client.Self_trace.set_enabled config.self_trace;
 
   exp
 

src/client/self_trace.ml

@@ -2,27 +2,12 @@ open Common_
 
 let enabled = Atomic.make false
 
-let tracer = Atomic.make OTEL.Tracer.default
-
 let[@inline] add_event (scope : OTEL.Span.t) ev = OTEL.Span.add_event scope ev
 
-let set_tracer tr = Atomic.set tracer tr
+let set_enabled b = Atomic.set enabled b
-
-let dummy_trace_id_ = OTEL.Trace_id.dummy
-
-let dummy_span_id = OTEL.Span_id.dummy
 
 let with_ ?kind ?attrs name f =
-  if Atomic.get enabled then (
+  if Atomic.get enabled then
-    let tracer = Atomic.get tracer in
+    OTEL.Tracer.with_ ~tracer:(OTEL.Trace_provider.get ()) ?kind ?attrs name f
-    OTEL.Tracer.with_ ~tracer ?kind ?attrs name f
+  else
-  ) else (
+    f OTEL.Span.dummy
-    (* A new scope is needed here because it might be modified *)
-    let span : OTEL.Span.t =
-      OTEL.Span.make ~trace_id:dummy_trace_id_ ~id:dummy_span_id ~start_time:0L
-        ~end_time:0L name
-    in
-    f span
-  )
-
-let set_enabled b = Atomic.set enabled b

src/client/self_trace.mli

@@ -1,5 +1,7 @@
-(** Mini tracing module for OTEL itself (disabled if [config.self_trace=false])
+(** Mini tracing module for OTEL itself.
-*)
+
+    When enabled via {!set_enabled}, emits spans via the current
+    {!OTEL.Trace_provider}. Disabled by default. *)
 
 open Common_
 
@@ -11,12 +13,8 @@ val with_ :
   string ->
   (OTEL.Span.t -> 'a) ->
   'a
-(** A simple way to create spans to instrument parts of the OTEL SDK itself. *)
+(** Instrument a section of SDK code with a span. No-ops when disabled. *)
-
-val set_tracer : OTEL.Tracer.t -> unit
-(** Set the tracer to use for self-tracing. We need to make sure it will not
-    lead to infinite loops (if the tracer itself is self-tracing, it might
-    invoke itself recursively, and so on). *)
 
 val set_enabled : bool -> unit
-(** Enable self tracing. A tracer must also be set. *)
+(** Enable or disable self-tracing. When enabled, uses the current
+    {!OTEL.Trace_provider} to emit spans. *)