From f653565658417417d25338993a073fcf8533665c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Wojciech=20Przytu=C5=82a?=
 <59482568+wprzytula@users.noreply.github.com>
Date: Thu, 8 Sep 2022 00:55:18 +0200
Subject: [PATCH] opentelemetry: fix `on_event` not respecting events' explicit
 parents (#2296)

One can want to have an event added from outside context of a span,
especially in an async code (e.g. between polls of the future, or
between polling multiple futures instrumented with that span). Then it
is expected that the event will be attached indeed to the span specified
as the parent and not the contextual one.

Fixes: #2295

See #2295
---
 tracing-opentelemetry/src/layer.rs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tracing-opentelemetry/src/layer.rs b/tracing-opentelemetry/src/layer.rs
index 533fe19406..b966e4372d 100644
--- a/tracing-opentelemetry/src/layer.rs
+++ b/tracing-opentelemetry/src/layer.rs
@@ -804,8 +804,8 @@ where
     /// [`ERROR`]: tracing::Level::ERROR
     /// [`Error`]: opentelemetry::trace::StatusCode::Error
     fn on_event(&self, event: &Event<'_>, ctx: Context<'_, S>) {
-        // Ignore events that are not in the context of a span
-        if let Some(span) = ctx.lookup_current() {
+        // Ignore events that have no explicit parent set *and* are not in the context of a span
+        if let Some(span) = ctx.event_span(event) {
             // Performing read operations before getting a write lock to avoid a deadlock
             // See https://github.com/tokio-rs/tracing/issues/763
             #[cfg(feature = "tracing-log")]