From 4ee29d8504964e7a94b205f17f033009100cfce6 Mon Sep 17 00:00:00 2001
From: Simon Cruanes <simon.cruanes.2007@m4x.org>
Date: Thu, 12 Jun 2025 09:14:45 -0400
Subject: [PATCH] feat: add `Globals.service_version`

---
 src/core/opentelemetry.ml | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/src/core/opentelemetry.ml b/src/core/opentelemetry.ml
index e494ea88..350568d8 100644
--- a/src/core/opentelemetry.ml
+++ b/src/core/opentelemetry.ml
@@ -687,6 +687,10 @@ module Globals = struct
   (** Unique identifier for the service *)
   let service_instance_id = ref None
 
+  (** Version for the service
+      @since NEXT_RELEASE *)
+  let service_version = ref None
+
   let instrumentation_library =
     default_instrumentation_scope ~version:"%%VERSION_NUM%%" ~name:"ocaml-otel"
       ()
@@ -746,6 +750,14 @@ module Globals = struct
           ~value:(Some (String_value v)) ()
         :: l
     in
+    let l =
+      match !service_version with
+      | None -> l
+      | Some v ->
+        default_key_value ~key:Conventions.Attributes.Service.version
+          ~value:(Some (String_value v)) ()
+        :: l
+    in
     l |> merge_global_attributes_
 end