[pbs-devel] [PATCH v5 proxmox-backup 4/4] fix #2996: client: allow optional match patterns for restore

[Christian Ebner]

When the user is only interested in a subset of the entries stored in
a file-level backup, it is convenient to be able to provide a list of
match patterns for the entries intended to be restored.

The required restore logic is already in place. Therefore, expose it
for the `proxmox-backup-client restore` command by adding the optional
array of patterns as command line argument and parse these before
passing them via the pxar restore options to the archive extractor.

Link to bugtracker issue:
https://bugzilla.proxmox.com/show_bug.cgi?id=2996

Signed-off-by: Christian Ebner <c.ebner at proxmox.com>
---
changes since version 4:
- rebased on current master

 proxmox-backup-client/src/main.rs | 29 ++++++++++++++++++++++++-----
 1 file changed, 24 insertions(+), 5 deletions(-)

diff --git a/proxmox-backup-client/src/main.rs b/proxmox-backup-client/src/main.rs
index e4034aa99..817235dbe 100644
--- a/proxmox-backup-client/src/main.rs
+++ b/proxmox-backup-client/src/main.rs
@@ -26,9 +26,9 @@ use pxar::accessor::{MaybeReady, ReadAt, ReadAtOperation};
 
 use pbs_api_types::{
     Authid, BackupDir, BackupGroup, BackupNamespace, BackupPart, BackupType, ClientRateLimitConfig,
-    CryptMode, Fingerprint, GroupListItem, PruneJobOptions, PruneListItem, RateLimitConfig,
-    SnapshotListItem, StorageStatus, BACKUP_ID_SCHEMA, BACKUP_NAMESPACE_SCHEMA, BACKUP_TIME_SCHEMA,
-    BACKUP_TYPE_SCHEMA,
+    CryptMode, Fingerprint, GroupListItem, PathPatterns, PruneJobOptions, PruneListItem,
+    RateLimitConfig, SnapshotListItem, StorageStatus, BACKUP_ID_SCHEMA, BACKUP_NAMESPACE_SCHEMA,
+    BACKUP_TIME_SCHEMA, BACKUP_TYPE_SCHEMA,
 };
 use pbs_client::catalog_shell::Shell;
 use pbs_client::pxar::{ErrorHandler as PxarErrorHandler, MetadataArchiveReader, PxarPrevRef};
@@ -1394,6 +1394,10 @@ We do not extract '.pxar' archives when writing to standard output.
                 type: ClientRateLimitConfig,
                 flatten: true,
             },
+            pattern: {
+                type: PathPatterns,
+                optional: true,
+            },
             "allow-existing-dirs": {
                 type: Boolean,
                 description: "Do not fail if directories already exists.",
@@ -1503,6 +1507,21 @@ async fn restore(
     let target = json::required_string_param(&param, "target")?;
     let target = if target == "-" { None } else { Some(target) };
 
+    let mut match_list = Vec::new();
+    if let Some(pattern) = param["pattern"].as_array() {
+        if target.is_none() {
+            bail!("patterns not allowed when restoring to stdout");
+        }
+
+        for p in pattern {
+            if let Some(pattern) = p.as_str() {
+                let match_entry =
+                    MatchEntry::parse_pattern(pattern, PatternFlag::PATH_NAME, MatchType::Include)?;
+                match_list.push(match_entry);
+            }
+        }
+    };
+
     let crypto = crypto_parameters(&param)?;
 
     let crypt_config = match crypto.enc_key {
@@ -1622,8 +1641,8 @@ async fn restore(
         let prelude_path = param["prelude-target"].as_str().map(PathBuf::from);
 
         let options = pbs_client::pxar::PxarExtractOptions {
-            match_list: &[],
-            extract_match_default: true,
+            match_list: &match_list,
+            extract_match_default: match_list.is_empty(),
             allow_existing_dirs,
             overwrite_flags,
             on_error,
-- 
2.39.2