[pbs-devel] [RFC PATCH proxmox-backup 1/6] api2: Add `protected` parameter to `finish` endpoint

[Christoph Heiss <c.heiss@proxmox.com>]

Groundwork for fixing #4289. This way, a backup can be set as protected
without a separate API call and thus avoid locking problems.

Signed-off-by: Christoph Heiss <c.heiss@proxmox.com>
---
 pbs-client/src/backup_writer.rs |  4 ++--
 src/api2/backup/environment.rs  | 11 +++++++++++
 src/api2/backup/mod.rs          | 25 ++++++++++++++++++++-----
 3 files changed, 33 insertions(+), 7 deletions(-)

diff --git a/pbs-client/src/backup_writer.rs b/pbs-client/src/backup_writer.rs
index be6da2a6..3e4b4878 100644
--- a/pbs-client/src/backup_writer.rs
+++ b/pbs-client/src/backup_writer.rs
@@ -165,10 +165,10 @@ impl BackupWriter {
         self.h2.upload("PUT", path, param, content_type, data).await
     }

-    pub async fn finish(self: Arc<Self>) -> Result<(), Error> {
+    pub async fn finish(self: Arc<Self>, param: Option<Value>) -> Result<(), Error> {
         let h2 = self.h2.clone();

-        h2.post("finish", None)
+        h2.post("finish", param)
             .map_ok(move |_| {
                 self.abort.abort();
             })
diff --git a/src/api2/backup/environment.rs b/src/api2/backup/environment.rs
index 4f07f9b4..05ee12ea 100644
--- a/src/api2/backup/environment.rs
+++ b/src/api2/backup/environment.rs
@@ -590,6 +590,17 @@ impl BackupEnvironment {
         Ok(())
     }

+    /// Sets the backup as protected.
+    pub fn set_protected(&self) -> Result<(), Error> {
+        let state = self.state.lock().unwrap();
+        state.ensure_unfinished()?;
+
+        let protected_path = self.backup_dir.protected_file();
+        std::fs::File::create(protected_path)
+            .map(|_| ())
+            .map_err(|err| format_err!("could not create protection file: {}", err))
+    }
+
     /// Mark backup as finished
     pub fn finish_backup(&self) -> Result<(), Error> {
         let mut state = self.state.lock().unwrap();
diff --git a/src/api2/backup/mod.rs b/src/api2/backup/mod.rs
index 90e2ea7e..decad084 100644
--- a/src/api2/backup/mod.rs
+++ b/src/api2/backup/mod.rs
@@ -344,10 +344,7 @@ const BACKUP_API_SUBDIRS: SubdirMap = &[
     ),
     (
         "finish",
-        &Router::new().post(&ApiMethod::new(
-            &ApiHandler::Sync(&finish_backup),
-            &ObjectSchema::new("Mark backup as finished.", &[]),
-        )),
+        &Router::new().post(&API_METHOD_FINISH_BACKUP),
     ),
     (
         "fixed_chunk",
@@ -771,12 +768,30 @@ fn close_fixed_index(
     Ok(Value::Null)
 }

+#[sortable]
+const API_METHOD_FINISH_BACKUP: ApiMethod = ApiMethod::new(
+    &ApiHandler::Sync(&finish_backup),
+    &ObjectSchema::new(
+        "Mark backup as finished.",
+        &sorted!([
+            ("protected", true, &BooleanSchema::new("Mark backup as protected").schema()),
+        ]),
+    ),
+);
+
 fn finish_backup(
-    _param: Value,
+    param: Value,
     _info: &ApiMethod,
     rpcenv: &mut dyn RpcEnvironment,
 ) -> Result<Value, Error> {
     let env: &BackupEnvironment = rpcenv.as_ref();
+    let protected = param["protected"].as_bool().unwrap_or(false);
+
+    if protected {
+        if let Err(err) = env.set_protected() {
+            env.log(format!("failed to set backup protected: {}", err));
+        }
+    }

     env.finish_backup()?;
     env.log("successfully finished backup");
--
2.34.1