Cleanup tags when OTLP sink is used

* Remove `otel.status` if it's just "OK" as it is not really helpful.
* Remove `otel.scope.name` as it just mirrors service name as a tag.
* Replace `otel.scope.version` with a process level `service.version`,
  which is more a appropriate and a stable version.

Author: bobrik

foundations/src/telemetry/otlp_conversion/common.rs

@@ -2,20 +2,10 @@ use crate::ServiceInfo;
 use opentelemetry_proto::tonic as otlp;
 use std::time::{Duration, SystemTime, UNIX_EPOCH};
 
-pub(super) fn convert_service_info_to_instrumentation_scope(
-    service_info: &ServiceInfo,
-) -> otlp::common::v1::InstrumentationScope {
-    otlp::common::v1::InstrumentationScope {
-        name: service_info.name.to_string(),
-        version: service_info.version.to_string(),
-        ..Default::default()
-    }
-}
-
 pub(super) fn convert_service_info_to_resource(
     service_info: &ServiceInfo,
 ) -> otlp::resource::v1::Resource {
-    let service_name_attr = otlp::common::v1::KeyValue {
+    let service_name = otlp::common::v1::KeyValue {
         key: "service.name".to_string(),
         value: Some(otlp::common::v1::AnyValue {
             value: Some(otlp::common::v1::any_value::Value::StringValue(
@@ -24,8 +14,17 @@ pub(super) fn convert_service_info_to_resource(
         }),
     };
 
+    let service_version = otlp::common::v1::KeyValue {
+        key: "service.version".to_string(),
+        value: Some(otlp::common::v1::AnyValue {
+            value: Some(otlp::common::v1::any_value::Value::StringValue(
+                service_info.version.to_string(),
+            )),
+        }),
+    };
+
     otlp::resource::v1::Resource {
-        attributes: vec![service_name_attr],
+        attributes: vec![service_name, service_version],
         dropped_attributes_count: 0,
         entity_refs: vec![],
     }

foundations/src/telemetry/otlp_conversion/tracing.rs

@@ -1,6 +1,4 @@
-use super::common::{
-    convert_service_info_to_instrumentation_scope, convert_service_info_to_resource, convert_time,
-};
+use super::common::{convert_service_info_to_resource, convert_time};
 use crate::ServiceInfo;
 use cf_rustracing::log::Log;
 use cf_rustracing::span::SpanReference;
@@ -104,12 +102,19 @@ pub(crate) fn convert_span(
     let span_state = span.context().state();
     let (status_code, attributes) = convert_tags(&span);
 
+    let status = (status_code == otlp::trace::v1::status::StatusCode::Error).then(|| {
+        otlp::trace::v1::Status {
+            code: status_code.into(),
+            message: Default::default(),
+        }
+    });
+
     otlp::trace::v1::ResourceSpans {
         resource: Some(convert_service_info_to_resource(service_info)),
         schema_url: Default::default(),
         scope_spans: vec![otlp::trace::v1::ScopeSpans {
             schema_url: Default::default(),
-            scope: Some(convert_service_info_to_instrumentation_scope(service_info)),
+            scope: None,
             spans: vec![otlp::trace::v1::Span {
                 trace_id: convert_trace_id(span_state),
                 span_id: span_state.span_id().to_be_bytes().to_vec(),
@@ -126,10 +131,7 @@ pub(crate) fn convert_span(
                 events: span.logs().iter().map(convert_log_entry).collect(),
                 dropped_links_count: Default::default(),
                 links: Default::default(),
-                status: Some(otlp::trace::v1::Status {
-                    code: status_code.into(),
-                    message: Default::default(),
-                }),
+                status,
             }],
         }],
     }