[pbs-devel] [PATCH v2 proxmox-backup 7/9] file-restore: fallback to mpxar if catalog not present

[Christian Ebner]

The `proxmox-file-restore list` command will uses the provided path to
lookup and list directory entries via the catalog. Fallback to using
the metadata archive if the catalog is not present for fast lookups in
a backup snapshot.

This is in preparation for dropping encoding of the catalog for
snapshots using split archive encoding. Proxmox VE's storage plugin
uses this to allow single file restore for LXCs.

Signed-off-by: Christian Ebner <c.ebner at proxmox.com>
---
 proxmox-file-restore/src/main.rs | 69 +++++++++++++++++++++++++-------
 1 file changed, 54 insertions(+), 15 deletions(-)

diff --git a/proxmox-file-restore/src/main.rs b/proxmox-file-restore/src/main.rs
index 0f16f3d42..a09873467 100644
--- a/proxmox-file-restore/src/main.rs
+++ b/proxmox-file-restore/src/main.rs
@@ -147,24 +147,63 @@ async fn list_files(
             Ok(entries)
         }
         ExtractPath::Pxar(file, mut path) => {
-            let index = client
-                .download_dynamic_index(&manifest, CATALOG_NAME)
+            if let Ok(file_info) = manifest.lookup_file_info(CATALOG_NAME) {
+                let index = client
+                    .download_dynamic_index(&manifest, CATALOG_NAME)
+                    .await?;
+                let most_used = index.find_most_used_chunks(8);
+                let chunk_reader = RemoteChunkReader::new(
+                    client.clone(),
+                    crypt_config,
+                    file_info.chunk_crypt_mode(),
+                    most_used,
+                );
+                let reader = BufferedDynamicReader::new(index, chunk_reader);
+                let mut catalog_reader = CatalogReader::new(reader);
+
+                let mut fullpath = file.into_bytes();
+                fullpath.append(&mut path);
+
+                catalog_reader.list_dir_contents(&fullpath)
+            } else {
+                if path.is_empty() {
+                    path = vec![b'/'];
+                }
+
+                let (archive_name, payload_archive_name) =
+                    pbs_client::tools::get_pxar_archive_names(&file, &manifest)?;
+
+                let (reader, archive_size) = get_remote_pxar_reader(
+                    &archive_name,
+                    client.clone(),
+                    &manifest,
+                    crypt_config.clone(),
+                )
                 .await?;
-            let most_used = index.find_most_used_chunks(8);
-            let file_info = manifest.lookup_file_info(CATALOG_NAME)?;
-            let chunk_reader = RemoteChunkReader::new(
-                client.clone(),
-                crypt_config,
-                file_info.chunk_crypt_mode(),
-                most_used,
-            );
-            let reader = BufferedDynamicReader::new(index, chunk_reader);
-            let mut catalog_reader = CatalogReader::new(reader);
 
-            let mut fullpath = file.into_bytes();
-            fullpath.append(&mut path);
+                let reader = if let Some(payload_archive_name) = payload_archive_name {
+                    let (payload_reader, payload_size) = get_remote_pxar_reader(
+                        &payload_archive_name,
+                        client,
+                        &manifest,
+                        crypt_config,
+                    )
+                    .await?;
+                    pxar::PxarVariant::Split(reader, (payload_reader, payload_size))
+                } else {
+                    pxar::PxarVariant::Unified(reader)
+                };
+
+                let accessor = Accessor::new(reader, archive_size).await?;
+                let path = OsStr::from_bytes(&path);
 
-            catalog_reader.list_dir_contents(&fullpath)
+                pbs_client::tools::pxar_metadata_catalog_lookup(
+                    accessor,
+                    &path,
+                    Some(&archive_name),
+                )
+                .await
+            }
         }
         ExtractPath::VM(file, path) => {
             let details = SnapRestoreDetails {
-- 
2.39.2