Fix(Backup): show a warning in the task log if a writer fails, an err…

…or if they all fails

@xen-orchestra/backups/_VmBackup.js

@@ -153,6 +153,9 @@ class VmBackup {
         errors.push(error)
         this.delete(writer)
         warn(warnMessage, { error, writer: writer.constructor.name })
+        Task.warning(
+          `the writer ${writer.constructor.name} has failed the step ${warnMessage} with error ${error.message}. It won't be used anymore in this job execution.`
+        )
       }
     })
     if (writers.size === 0) {
@@ -433,6 +436,7 @@ class VmBackup {
     )
 
     await this._callWriters(async writer => {
+      await Task.run({ name: 'beforeBackup' }, () => writer.beforeBackup())
       await writer.beforeBackup()
       $defer(async () => {
         await writer.afterBackup()

CHANGELOG.unreleased.md

@@ -11,6 +11,8 @@
 
 > Users must be able to say: “I had this issue, happy to know it's fixed”
 
+- [Backup] show a warning in the task log if a writer fails, an error if they all fail (PR [#6266](https://github.com/vatesfr/xen-orchestra/pull/6266))
+
 ### Packages to release
 
 > When modifying a package, add it here with its release type.
@@ -26,6 +28,7 @@
 <!--packages-start-->
 
 - @xen-orchestra/xapi minor
+- @xen-orchestra/backups minor
 - xo-server patch
 
 <!--packages-end-->