Flush support bundle logs when copied from stream (#8716)

Fixes #8711

Author: smklein

nexus/src/app/background/tasks/support_bundle_collector.rs

@@ -51,6 +51,7 @@ use std::num::NonZeroU64;
 use std::sync::Arc;
 use tokio::io::AsyncReadExt;
 use tokio::io::AsyncSeekExt;
+use tokio::io::AsyncWriteExt;
 use tokio::io::SeekFrom;
 use tufaceous_artifact::ArtifactHash;
 use zip::ZipArchive;
@@ -983,29 +984,30 @@ async fn save_zone_log_zip_or_error(
         Ok(res) => {
             let bytestream = res.into_inner();
             let output_dir = path.join(format!("logs/{zone}"));
-            let output_file = output_dir.join("logs.zip");
+            let output_path = output_dir.join("logs.zip");
 
             // Ensure the logs output directory exists.
             tokio::fs::create_dir_all(&output_dir).await.with_context(
                 || format!("failed to create output directory: {output_dir}"),
             )?;
 
             let mut file =
-                tokio::fs::File::create(&output_file).await.with_context(
-                    || format!("failed to create file: {output_file}"),
+                tokio::fs::File::create(&output_path).await.with_context(
+                    || format!("failed to create file: {output_path}"),
                 )?;
 
             let stream = bytestream.into_inner().map(|chunk| {
                 chunk.map_err(|e| std::io::Error::other(e.to_string()))
             });
             let mut reader = tokio_util::io::StreamReader::new(stream);
             let _nbytes = tokio::io::copy(&mut reader, &mut file).await?;
+            file.flush().await?;
 
             // Unpack the zip so we don't end up with zip files inside of our
             // final zip
-            let zipfile = output_file.clone();
+            let zipfile_path = output_path.clone();
             tokio::task::spawn_blocking(move || {
-                extract_zip_file(&output_dir, &zipfile)
+                extract_zip_file(&output_dir, &zipfile_path)
             })
             .await
             .map_err(|join_error| {
@@ -1014,12 +1016,12 @@ async fn save_zone_log_zip_or_error(
             })??;
 
             // Cleanup the zip file since we no longer need it
-            if let Err(e) = tokio::fs::remove_file(&output_file).await {
+            if let Err(e) = tokio::fs::remove_file(&output_path).await {
                 error!(
                     logger,
                     "failed to cleanup temporary logs zip file";
                     "error" => %e,
-                    "file" => %output_file,
+                    "file" => %output_path,
 
                 );
             }