Add Span to repository traversal

ldp/src/traverse.rs

@@ -7,6 +7,7 @@ use reqwest_middleware::reqwest::Url;
 use std::collections::HashSet;
 use std::pin::Pin;
 use std::task::{Context, Poll, ready};
+use tracing::debug_span;
 
 /// Recursively traverse an entire repository.
 ///
@@ -21,6 +22,7 @@ pub struct Traverse<'a> {
     visited_urls: HashSet<Url>,
     pending_urls: HashSet<Url>,
     parallelism: Option<usize>,
+    span: tracing::Span,
 }
 
 impl<'a> Traverse<'a> {
@@ -35,6 +37,7 @@ impl<'a> Traverse<'a> {
             visited_urls: HashSet::new(),
             pending_urls: HashSet::new(),
             parallelism,
+            span: debug_span!("Traverse Repository", %root),
         };
         this.visited_urls.insert(root.clone());
         this.stream
@@ -89,6 +92,7 @@ impl<'a> Stream for Traverse<'a> {
     type Item = crate::Result<RdfSource<Dataset>>;
 
     fn poll_next(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Option<Self::Item>> {
+        let _enter = self.span.clone().entered();
         let result = match ready!(self.stream.poll_next_unpin(cx)) {
             Some(Ok(document)) => {
                 self.visited_urls.insert(document.origin().clone());