tag subrequests as such

This adds a hook during the flow where we move the write permit around
for subrequests to refresh stale assets to tag the parent span as being
part of a subrequest.

3 files changed, 10 insertions, 1 deletions

diff --git a/.bleep b/.bleep
index 334fc92..54ac764 100644
--- a/.bleep
+++ b/.bleep
@@ -1 +1 @@
-3dd34515725af2df875219491ab8542ecf59bd2b
\ No newline at end of file
+b6df57d294b9ccbe3a623b9ccd005e407cacc5a5
\ No newline at end of file
diff --git a/pingora-cache/src/lib.rs b/pingora-cache/src/lib.rs
index 1a97041..2aa2f7c 100644
--- a/pingora-cache/src/lib.rs
+++ b/pingora-cache/src/lib.rs
@@ -1142,6 +1142,14 @@ impl HttpCache {
             predictor.mark_uncacheable(self.cache_key(), reason);
         }
     }
+
+    /// Tag all spans as being part of a subrequest.
+    pub fn tag_as_subrequest(&mut self) {
+        self.inner_mut()
+            .traces
+            .cache_span
+            .set_tag(|| Tag::new("is_subrequest", true))
+    }
 }
 
 /// Set the header compression dictionary, which helps serialize http header.
diff --git a/pingora-proxy/src/proxy_cache.rs b/pingora-proxy/src/proxy_cache.rs
index e9914cf..865c592 100644
--- a/pingora-proxy/src/proxy_cache.rs
+++ b/pingora-proxy/src/proxy_cache.rs
@@ -153,6 +153,7 @@ impl<SV> HttpProxy<SV> {
                                 {
                                     // Put the write lock in the request
                                     session.cache.set_write_lock(write_lock);
+                                    session.cache.tag_as_subrequest();
                                     // and then let it go to upstream
                                     break None;
                                 }