Remove fancy follows-from code

Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 name = "tracing-awc"
 description = "Tracing instrumentation for the awc http client"
-version = "0.1.0-beta.12"
+version = "0.1.0-beta.13"
 authors = ["asonix <asonix@asonix.dog"]
 edition = "2018"
 license = "AGPL-3.0"

src/lib.rs

@@ -11,7 +11,7 @@ use std::{
     pin::Pin,
     task::{Context, Poll},
 };
-use tracing::{instrument::Instrumented, Id, Instrument, Span};
+use tracing::{instrument::Instrumented, Instrument, Span};
 
 #[cfg(feature = "opentelemetry_0_13")]
 use opentelemetry_0_13_pkg as opentelemetry;
@@ -138,39 +138,6 @@ where
     }
 }
 
-enum IdOrSpan {
-    Id(Option<Id>),
-    Span(Span),
-}
-
-impl IdOrSpan {
-    fn from_id(id: Option<Id>) -> Self {
-        IdOrSpan::Id(id)
-    }
-
-    fn take(&mut self) -> Self {
-        std::mem::replace(self, IdOrSpan::Id(None))
-    }
-
-    fn span(&self) -> Option<&Span> {
-        match self {
-            IdOrSpan::Span(ref span) => Some(span),
-            _ => None,
-        }
-    }
-
-    fn as_span(&mut self, f: impl Fn(Option<Id>) -> Span) -> &Span {
-        let span = match self.take() {
-            Self::Id(id) => f(id),
-            Self::Span(span) => span,
-        };
-
-        *self = Self::Span(span);
-
-        self.span().expect("Span should always exist")
-    }
-}
-
 pin_project_lite::pin_project! {
     pub struct TracingFuture<F> {
         span: Span,
@@ -204,8 +171,10 @@ where
                         }
 
                         ConnectResponse::Client(client_response.map_body(|_, payload| {
-                            let instrumented =
-                                InstrumentedBody::new(IdOrSpan::from_id(span.id()), payload);
+                            let body_span =
+                                tracing::info_span!(parent: None, "HTTP Client Response Body");
+                            body_span.follows_from(span.id());
+                            let instrumented = InstrumentedBody::new(body_span, payload);
                             let pinned: Pin<Box<dyn Stream<Item = Result<Bytes, PayloadError>>>> =
                                 Box::pin(instrumented);
 
@@ -243,7 +212,7 @@ where
 
 pin_project_lite::pin_project! {
     struct InstrumentedBody<S> {
-        span: IdOrSpan,
+        span: Span,
 
         #[pin]
         body: S,
@@ -254,7 +223,7 @@ impl<S> InstrumentedBody<S>
 where
     S: Stream<Item = Result<Bytes, PayloadError>>,
 {
-    fn new(span: IdOrSpan, body: S) -> InstrumentedBody<S> {
+    fn new(span: Span, body: S) -> InstrumentedBody<S> {
         InstrumentedBody { span, body }
     }
 }
@@ -268,11 +237,7 @@ where
     fn poll_next(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Option<Self::Item>> {
         let this = self.as_mut().project();
 
-        let span = this.span.as_span(|id| {
-            let span = tracing::info_span!("HTTP Client Response Body");
-            span.follows_from(id);
-            span
-        });
+        let span = this.span;
         let body = this.body;
 
         span.in_scope(|| body.poll_next(cx))