From 752f2ea565c5a5ee7174c3836d2e7b2c1e47c463 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Oto=20Pet=C5=99=C3=ADk?= <oto.petrik@gmail.com>
Date: Sat, 30 Jul 2022 02:22:40 +0200
Subject: [PATCH] Avoid reboot when resizing disks. (#104)

There is no need to shutdown VM before resizing disks.
In addition to boot time, system in VM can be configured to resize
partitions and filesystems in response to udev events.

Co-authored-by: Pavel Boldyrev <627562+bpg@users.noreply.github.com>
---
 proxmoxtf/resource_virtual_environment_vm.go | 34 +++++++++++---------
 1 file changed, 18 insertions(+), 16 deletions(-)

diff --git a/proxmoxtf/resource_virtual_environment_vm.go b/proxmoxtf/resource_virtual_environment_vm.go
index 0c0f65e2..a263d18b 100644
--- a/proxmoxtf/resource_virtual_environment_vm.go
+++ b/proxmoxtf/resource_virtual_environment_vm.go
@@ -3463,8 +3463,6 @@ func resourceVirtualEnvironmentVMUpdate(ctx context.Context, d *schema.ResourceD
 				}
 			}
 		}
-
-		rebootRequired = true
 	}
 
 	// Prepare the new cloud-init configuration.
@@ -3655,6 +3653,8 @@ func resourceVirtualEnvironmentVMUpdateDiskLocationAndSize(ctx context.Context,
 		var diskMoveBodies []*proxmox.VirtualEnvironmentVMMoveDiskRequestBody
 		var diskResizeBodies []*proxmox.VirtualEnvironmentVMResizeDiskRequestBody
 
+		var shutdownForDisksRequired bool = false
+
 		for prefix, diskMap := range diskOldEntries {
 			for oldKey, oldDisk := range diskMap {
 				if _, present := diskNewEntries[prefix][oldKey]; !present {
@@ -3669,6 +3669,9 @@ func resourceVirtualEnvironmentVMUpdateDiskLocationAndSize(ctx context.Context,
 						Disk:               *oldDisk.Interface,
 						TargetStorage:      *diskNewEntries[prefix][oldKey].ID,
 					})
+
+					// Cannot be done while VM is running.
+					shutdownForDisksRequired = true
 				}
 
 				if *oldDisk.SizeInt <= *diskNewEntries[prefix][oldKey].SizeInt {
@@ -3680,21 +3683,17 @@ func resourceVirtualEnvironmentVMUpdateDiskLocationAndSize(ctx context.Context,
 			}
 		}
 
-		if len(diskMoveBodies) > 0 || len(diskResizeBodies) > 0 {
-			if !template {
-				forceStop := proxmox.CustomBool(true)
-				shutdownTimeout := d.Get(mkResourceVirtualEnvironmentVMTimeoutShutdownVM).(int)
+		if shutdownForDisksRequired && !template {
+			forceStop := proxmox.CustomBool(true)
+			shutdownTimeout := d.Get(mkResourceVirtualEnvironmentVMTimeoutShutdownVM).(int)
 
-				err = veClient.ShutdownVM(ctx, nodeName, vmID, &proxmox.VirtualEnvironmentVMShutdownRequestBody{
-					ForceStop: &forceStop,
-					Timeout:   &shutdownTimeout,
-				}, shutdownTimeout+30)
-				if err != nil {
-					return diag.FromErr(err)
-				}
+			err = veClient.ShutdownVM(ctx, nodeName, vmID, &proxmox.VirtualEnvironmentVMShutdownRequestBody{
+				ForceStop: &forceStop,
+				Timeout:   &shutdownTimeout,
+			}, shutdownTimeout+30)
+			if err != nil {
+				return diag.FromErr(err)
 			}
-
-			reboot = false
 		}
 
 		for _, reqBody := range diskMoveBodies {
@@ -3712,12 +3711,15 @@ func resourceVirtualEnvironmentVMUpdateDiskLocationAndSize(ctx context.Context,
 			}
 		}
 
-		if (len(diskMoveBodies) > 0 || len(diskResizeBodies) > 0) && started && !template {
+		if shutdownForDisksRequired && started && !template {
 			startVMTimeout := d.Get(mkResourceVirtualEnvironmentVMTimeoutStartVM).(int)
 			err = veClient.StartVM(ctx, nodeName, vmID, startVMTimeout)
 			if err != nil {
 				return diag.FromErr(err)
 			}
+
+			// This concludes an equivalent of a reboot, avoid doing another.
+			reboot = false
 		}
 	}