fix(backups/ImportVmBackup): use transfered size instead of backup size

Backup size is smaller in case of delta VHDs.

@xen-orchestra/backups/ImportVmBackup.js

@@ -3,6 +3,7 @@ const assert = require('assert')
 const { formatFilenameDate } = require('./_filenameDate')
 const { importDeltaVm } = require('./_deltaVm')
 const { Task } = require('./Task')
+const { watchStreamSize } = require('./_watchStreamSize')
 
 exports.ImportVmBackup = class ImportVmBackup {
   constructor({ adapter, metadata, srUuid, xapi, settings: { newMacAddresses } = {} }) {
@@ -18,13 +19,17 @@ exports.ImportVmBackup = class ImportVmBackup {
     const metadata = this._metadata
     const isFull = metadata.mode === 'full'
 
+    const sizeContainer = { size: 0 }
+
     let backup
     if (isFull) {
       backup = await adapter.readFullVmBackup(metadata)
+      watchStreamSize(backup, sizeContainer)
     } else {
       assert.strictEqual(metadata.mode, 'delta')
 
       backup = await adapter.readDeltaVmBackup(metadata)
+      Object.values(backup.streams).forEach(stream => watchStreamSize(stream, sizeContainer))
     }
 
     return Task.run(
@@ -52,7 +57,7 @@ exports.ImportVmBackup = class ImportVmBackup {
         ])
 
         return {
-          size: metadata.size,
+          size: sizeContainer.size,
           id: await xapi.getField('VM', vmRef, 'uuid'),
         }
       }

@xen-orchestra/backups/_watchStreamSize.js

@@ -1,5 +1,4 @@
-exports.watchStreamSize = function watchStreamSize(stream) {
-  const container = { size: 0 }
+exports.watchStreamSize = function watchStreamSize(stream, container = { size: 0 }) {
   stream.on('data', data => {
     container.size += data.length
   })

CHANGELOG.unreleased.md

@@ -17,6 +17,7 @@
 - [Backup] Fix `vm.refresh_snapshots is not a function` error
 - [Backup] Fix `cannot read property "length" of undefined` when using _delete first_ [Forum post](https://xcp-ng.org/forum/topic/4440/error-on-delta-backup-cannot-read-property-length-of-undefined)
 - [Delta backup] Fix merge task not under corresponding remote and missing merge size in summary [#5708](https://github.com/vatesfr/xen-orchestra/issues/5708)
+- [Delta backup restore] Fix incorrect reported size (and speed)
 - [Settings/Logs] Correctly hide `pool.listMissingPatches` and `host.stats` errors
 - [Plugins] Fix `strict mode: unknown keyword` when configuring some plugins