feat(tracing): add net.peer.name attribute if balancer_data.hostname is available

CHANGELOG.md

@@ -88,6 +88,8 @@
   [#11082](https://github.com/Kong/kong/pull/11082)
 - Fix an issue where the router of flavor `expressions` can not configure https redirection.
   [#11166](https://github.com/Kong/kong/pull/11166)
+- Added new span attribute `net.peer.name` if balancer_data.hostname is available.
+  [#10723](https://github.com/Kong/kong/pull/10729)
 
 #### Admin API
 

kong/tracing/instrumentation.lua

@@ -111,6 +111,10 @@ function _M.balancer(ctx)
         span:set_attribute("http.status_code", try.code)
         span:set_status(2)
       end
+
+      if balancer_data.hostname ~= nil then
+        span:set_attribute("net.peer.name", balancer_data.hostname)
+      end
 
       if try.balancer_latency_ns ~= nil then
         local try_upstream_connect_time = (tonumber(upstream_connect_time[i], 10) or 0) * 1000
@@ -128,6 +132,10 @@ function _M.balancer(ctx)
         span:set_attribute("http.status_code", try.code)
         span:set_status(2)
       end
+
+      if balancer_data.hostname ~= nil then
+        span:set_attribute("net.peer.name", balancer_data.hostname)
+      end
 
       local upstream_finish_time = ctx.KONG_BODY_FILTER_ENDED_AT_NS
       span:finish(upstream_finish_time)

spec/02-integration/14-tracing/01-instrumentations_spec.lua

@@ -409,6 +409,7 @@ for _, strategy in helpers.each_strategy() do
         assert_has_attributes(balancer_span, {
           ["net.peer.ip"] = "127.0.0.1",
           ["net.peer.port"] = "%d+",
+          ["net.peer.name"]  = "127.0.0.1",
         })
 
         assert_has_attributes(db_span, {