do not expose the trace_id in response header right now

NEXT_CHANGELOG.md

@@ -36,7 +36,7 @@ By [@garypen](https://github.com/garypen) in https://github.com/apollographql/ro
 
 ### Add `trace_id` in logs to identify all logs related to a specific request ([Issue #1981](https://github.com/apollographql/router/issues/1981))
 
-It automatically adds a `trace_id` on logs to identify which log is related to a specific request. Also adds `apollo_trace_id` in response headers to help the client to identify logs for this request.
+It automatically adds a `trace_id` on logs to identify which log is related to a specific request.
 
 Example of logs in text:
 

apollo-router/src/plugins/telemetry/tracing/apollo_telemetry.rs

@@ -427,17 +427,18 @@ impl Exporter {
             .map(|(header_name, value)| (header_name.to_lowercase(), Values { value }))
             .collect();
         // For now, only trace_id
-        let mut response_headers = HashMap::with_capacity(1);
-        response_headers.insert(
-            String::from("apollo_trace_id"),
-            Values {
-                value: vec![span.span_context.trace_id().to_string()],
-            },
-        );
+        // let mut response_headers = HashMap::with_capacity(1);
+        // FIXME: uncomment later
+        // response_headers.insert(
+        //     String::from("apollo_trace_id"),
+        //     Values {
+        //         value: vec![span.span_context.trace_id().to_string()],
+        //     },
+        // );
         Http {
             method: method.into(),
             request_headers,
-            response_headers,
+            response_headers: HashMap::new(),
             status_code: 0,
         }
     }

apollo-router/src/services/supergraph_service.rs

@@ -3,11 +3,9 @@
 use std::sync::Arc;
 use std::task::Poll;
 
-use axum::headers::HeaderName;
 use futures::future::BoxFuture;
 use futures::stream::StreamExt;
 use futures::TryFutureExt;
-use http::HeaderValue;
 use http::StatusCode;
 use indexmap::IndexMap;
 use multimap::MultiMap;
@@ -40,7 +38,6 @@ use crate::query_planner::CachingQueryPlanner;
 use crate::router_factory::Endpoint;
 use crate::router_factory::SupergraphServiceFactory;
 use crate::services::layers::ensure_query_presence::EnsureQueryPresence;
-use crate::tracer::TraceId;
 use crate::Configuration;
 use crate::Context;
 use crate::ExecutionRequest;
@@ -103,8 +100,8 @@ where
         let schema = self.schema.clone();
 
         let context_cloned = req.context.clone();
-        let fut = service_call(planning, execution, schema, req)
-            .or_else(|error: BoxError| async move {
+        let fut =
+            service_call(planning, execution, schema, req).or_else(|error: BoxError| async move {
                 let errors = vec![crate::error::Error {
                     message: error.to_string(),
                     extensions: serde_json_bytes::json!({
@@ -122,19 +119,20 @@ where
                     .context(context_cloned)
                     .build()
                     .expect("building a response like this should not fail"))
-            })
-            .and_then(|mut res| async move {
-                if let Some(trace_id) = TraceId::maybe_new().map(|t| t.to_string()) {
-                    let header_value = HeaderValue::from_str(trace_id.as_str());
-                    if let Ok(header_value) = header_value {
-                        res.response
-                            .headers_mut()
-                            .insert(HeaderName::from_static("apollo_trace_id"), header_value);
-                    }
-                }
-
-                Ok(res)
             });
+        // FIXME: Enable it later
+        // .and_then(|mut res| async move {
+        //     if let Some(trace_id) = TraceId::maybe_new().map(|t| t.to_string()) {
+        //         let header_value = HeaderValue::from_str(trace_id.as_str());
+        //         if let Ok(header_value) = header_value {
+        //             res.response
+        //                 .headers_mut()
+        //                 .insert(HeaderName::from_static("apollo_trace_id"), header_value);
+        //         }
+        //     }
+
+        //     Ok(res)
+        // });
 
         Box::pin(fut)
     }