From be97e0a55b9ab76119b00ef944a4810e3aea0e96 Mon Sep 17 00:00:00 2001
From: Dominik Csapak <d.csapak@proxmox.com>
Date: Thu, 5 May 2022 14:12:36 +0200
Subject: [PATCH] tape: add namespaces mapping type

and the relevant parser for it

Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>
---
 pbs-api-types/src/datastore.rs | 33 +++++++++++++++
 src/api2/tape/restore.rs       | 74 ++++++++++++++++++++++++++++++++--
 2 files changed, 103 insertions(+), 4 deletions(-)

diff --git a/pbs-api-types/src/datastore.rs b/pbs-api-types/src/datastore.rs
index 95ef7120..88179832 100644
--- a/pbs-api-types/src/datastore.rs
+++ b/pbs-api-types/src/datastore.rs
@@ -1464,6 +1464,39 @@ pub const ADMIN_DATASTORE_PRUNE_RETURN_TYPE: ReturnType = ReturnType {
     .schema(),
 };
 
+#[api(
+    properties: {
+        store: {
+            schema: DATASTORE_SCHEMA,
+        },
+        "max-depth": {
+            schema: NS_MAX_DEPTH_SCHEMA,
+            optional: true,
+        },
+     },
+)]
+#[derive(Serialize, Deserialize)]
+#[serde(rename_all = "kebab-case")]
+/// A namespace mapping
+pub struct TapeRestoreNamespace {
+    /// The source datastore
+    pub store: String,
+    /// The source namespace. Root namespace if omitted.
+    pub source: Option<BackupNamespace>,
+    /// The target namespace,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub target: Option<BackupNamespace>,
+    /// The (optional) recursion depth
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub max_depth: Option<usize>,
+}
+
+pub const TAPE_RESTORE_NAMESPACE_SCHEMA: Schema = StringSchema::new("A namespace mapping")
+    .format(&ApiStringFormat::PropertyString(
+        &TapeRestoreNamespace::API_SCHEMA,
+    ))
+    .schema();
+
 /// Parse snapshots in the form 'ns/foo/ns/bar/ct/100/1970-01-01T00:00:00Z'
 /// into a [`BackupNamespace`] and [`BackupDir`]
 pub fn parse_ns_and_snapshot(input: &str) -> Result<(BackupNamespace, BackupDir), Error> {
diff --git a/src/api2/tape/restore.rs b/src/api2/tape/restore.rs
index bbd3170c..c91a6e92 100644
--- a/src/api2/tape/restore.rs
+++ b/src/api2/tape/restore.rs
@@ -10,16 +10,17 @@ use serde_json::Value;
 
 use proxmox_io::ReadExt;
 use proxmox_router::{Permission, Router, RpcEnvironment, RpcEnvironmentType};
-use proxmox_schema::api;
+use proxmox_schema::{api, ApiType};
 use proxmox_section_config::SectionConfigData;
 use proxmox_sys::fs::{replace_file, CreateOptions};
 use proxmox_sys::{task_log, task_warn, WorkerTaskContext};
 use proxmox_uuid::Uuid;
 
 use pbs_api_types::{
-    Authid, BackupNamespace, CryptMode, Operation, Userid, DATASTORE_MAP_ARRAY_SCHEMA,
-    DATASTORE_MAP_LIST_SCHEMA, DRIVE_NAME_SCHEMA, PRIV_DATASTORE_BACKUP, PRIV_DATASTORE_MODIFY,
-    PRIV_TAPE_READ, TAPE_RESTORE_SNAPSHOT_SCHEMA, UPID_SCHEMA,
+    Authid, BackupNamespace, CryptMode, Operation, TapeRestoreNamespace, Userid,
+    DATASTORE_MAP_ARRAY_SCHEMA, DATASTORE_MAP_LIST_SCHEMA, DRIVE_NAME_SCHEMA, MAX_NAMESPACE_DEPTH,
+    PRIV_DATASTORE_BACKUP, PRIV_DATASTORE_MODIFY, PRIV_TAPE_READ, TAPE_RESTORE_SNAPSHOT_SCHEMA,
+    UPID_SCHEMA,
 };
 use pbs_config::CachedUserInfo;
 use pbs_datastore::dynamic_index::DynamicIndexReader;
@@ -56,6 +57,71 @@ pub struct DataStoreMap {
     default: Option<Arc<DataStore>>,
 }
 
+struct NamespaceMap {
+    map: HashMap<String, HashMap<BackupNamespace, (BackupNamespace, usize)>>,
+}
+
+impl TryFrom<Vec<String>> for NamespaceMap {
+    type Error = Error;
+
+    fn try_from(mappings: Vec<String>) -> Result<Self, Error> {
+        let mut map = HashMap::new();
+
+        let mappings = mappings.into_iter().map(|s| {
+            let value = TapeRestoreNamespace::API_SCHEMA.parse_property_string(&s)?;
+            let value: TapeRestoreNamespace = serde_json::from_value(value)?;
+            Ok::<_, Error>(value)
+        });
+
+        for mapping in mappings {
+            let mapping = mapping?;
+            let source = mapping.source.unwrap_or_default();
+            let target = mapping.target.unwrap_or_default();
+            let max_depth = mapping.max_depth.unwrap_or(MAX_NAMESPACE_DEPTH);
+
+            let ns_map: &mut HashMap<BackupNamespace, (BackupNamespace, usize)> =
+                map.entry(mapping.store).or_insert_with(HashMap::new);
+
+            if ns_map.insert(source, (target, max_depth)).is_some() {
+                bail!("duplicate mapping found");
+            }
+        }
+
+        Ok(Self { map })
+    }
+}
+
+impl NamespaceMap {
+    fn used_namespaces<'a>(&self, datastore: &str) -> HashSet<BackupNamespace> {
+        let mut set = HashSet::new();
+        if let Some(mapping) = self.map.get(datastore) {
+            for (ns, _) in mapping.values() {
+                set.insert(ns.clone());
+            }
+        }
+
+        set
+    }
+
+    fn get_namespaces(&self, source_ds: &str, source_ns: &BackupNamespace) -> Vec<BackupNamespace> {
+        if let Some(mapping) = self.map.get(source_ds) {
+            return mapping
+                .iter()
+                .filter_map(|(ns, (target_ns, max_depth))| {
+                    // filter out prefixes which are too long
+                    if ns.depth() > source_ns.depth() || source_ns.depth() - ns.depth() > *max_depth
+                    {
+                        return None;
+                    }
+                    source_ns.map_prefix(ns, target_ns).ok()
+                })
+                .collect();
+        }
+
+        vec![]
+    }
+}
+
 impl TryFrom<String> for DataStoreMap {
     type Error = Error;