fix(xo-server/backup): restore VM from proxied remote (#6179)

CHANGELOG.unreleased.md

@@ -13,6 +13,7 @@
 
 - [Plugins] Automatically configure plugins when a configuration file is imported (PR [#6171](https://github.com/vatesfr/xen-orchestra/pull/6171))
 - [VMDK Export] Fix `VBOX_E_FILE_ERROR (0x80BB0004)` when importing in VirtualBox (PR [#6163](https://github.com/vatesfr/xen-orchestra/pull/6163))
+- [Backup] Fix "Cannot read properties of undefined" error when restoring from a proxied remote (PR [#6179](https://github.com/vatesfr/xen-orchestra/pull/6179))
 
 ### Packages to release
 

packages/xo-server/src/_handleBackupLog.mjs

@@ -1,7 +1,28 @@
+function forwardResult(log) {
+  if (log.status === 'failure') {
+    throw log.result
+  }
+  return log.result
+}
+
 // it records logs generated by `@xen-orchestra/backups/Task#run`
-export const handleBackupLog = (log, { logger, localTaskIds, runJobId, handleRootTaskId }) => {
+export const handleBackupLog = (log, { logger, localTaskIds, rootTaskId, runJobId = rootTaskId, handleRootTaskId }) => {
   const { event, message, taskId } = log
 
+  // If `runJobId` is defined, it means that the root task is already handled by `runJob`
+  if (runJobId !== undefined) {
+    // Ignore the start of the root task
+    if (event === 'start' && log.parentId === undefined) {
+      localTaskIds[taskId] = runJobId
+      return
+    }
+
+    // Return/throw the result of the root task
+    if (event === 'end' && localTaskIds[taskId] === runJobId) {
+      return forwardResult(log)
+    }
+  }
+
   const common = {
     data: log.data,
     event: 'task.' + event,
@@ -9,19 +30,6 @@ export const handleBackupLog = (log, { logger, localTaskIds, runJobId, handleRoo
     status: log.status,
   }
 
-  // ignore root task (already handled by runJob)
-  if (runJobId !== undefined) {
-    if (event === 'start' && log.parentId === undefined) {
-      localTaskIds[taskId] = runJobId
-      return
-    } else if (event === 'end' && localTaskIds[taskId] === runJobId) {
-      if (log.status === 'failure') {
-        throw log.result
-      }
-      return log.result
-    }
-  }
-
   if (event === 'start') {
     const { parentId } = log
     if (parentId === undefined) {
@@ -34,4 +42,9 @@ export const handleBackupLog = (log, { logger, localTaskIds, runJobId, handleRoo
     common.taskId = localTaskIds[taskId]
     logger.notice(message, common)
   }
+
+  // special case for the end of the root task: return/throw the result
+  if (event === 'end' && localTaskIds[taskId] === rootTaskId) {
+    return forwardResult(log)
+  }
 }

packages/xo-server/src/xo-mixins/backups-ng/index.mjs

@@ -423,6 +423,7 @@ export default class BackupNg {
             result = handleBackupLog(log, {
               logger,
               localTaskIds,
+              rootTaskId,
               handleRootTaskId: id => {
                 this._runningRestores.add(id)
                 rootTaskId = id