[pbs-devel] [PATCH v3 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 2:
- use of `PathPatterns` instead of Array of Strings for pattern
  parameters
- use simple reference instead of `as_slice()` when passing vector of
  patterns

 proxmox-backup-client/src/main.rs | 27 +++++++++++++++++++++++----
 1 file changed, 23 insertions(+), 4 deletions(-)

diff --git a/proxmox-backup-client/src/main.rs b/proxmox-backup-client/src/main.rs
index f1c7fbf93..9cc6f889a 100644
--- a/proxmox-backup-client/src/main.rs
+++ b/proxmox-backup-client/src/main.rs
@@ -26,8 +26,8 @@ use pxar::accessor::{MaybeReady, ReadAt, ReadAtOperation};
 
 use pbs_api_types::{
     Authid, BackupDir, BackupGroup, BackupNamespace, BackupPart, BackupType, CryptMode,
-    Fingerprint, GroupListItem, PruneJobOptions, PruneListItem, RateLimitConfig, SnapshotListItem,
-    StorageStatus, BACKUP_ID_SCHEMA, BACKUP_NAMESPACE_SCHEMA, BACKUP_TIME_SCHEMA,
+    Fingerprint, GroupListItem, PathPatterns, PruneJobOptions, PruneListItem, RateLimitConfig,
+    SnapshotListItem, StorageStatus, BACKUP_ID_SCHEMA, BACKUP_NAMESPACE_SCHEMA, BACKUP_TIME_SCHEMA,
     BACKUP_TYPE_SCHEMA, TRAFFIC_CONTROL_BURST_SCHEMA, TRAFFIC_CONTROL_RATE_SCHEMA,
 };
 use pbs_client::catalog_shell::Shell;
@@ -1389,6 +1389,10 @@ We do not extract '.pxar' archives when writing to standard output.
 
 "###
             },
+            pattern: {
+                type: PathPatterns,
+                optional: true,
+            },
             rate: {
                 schema: TRAFFIC_CONTROL_RATE_SCHEMA,
                 optional: true,
@@ -1514,6 +1518,21 @@ 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!("matches 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 {
@@ -1635,8 +1654,8 @@ async fn restore(
             .map(|path| PathBuf::from(path));
 
         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