fix(lxc): fixes for datastore-backed volume mounts (#772)

Signed-off-by: Pavel Boldyrev <627562+bpg@users.noreply.github.com>

docs/resources/virtual_environment_container.md

@@ -47,8 +47,16 @@ resource "proxmox_virtual_environment_container" "ubuntu_container" {
   }
 
   mount_point {
+    # bind mount, *requires* root@pam authentication
     volume = "/mnt/bindmounts/shared"
-    path   = "/shared"
+    path   = "/mnt/shared"
+  }
+
+  mount_point {
+    # volume mount, a new volume will be created by PVE
+    volume = "local-lvm"
+    size   = "10G"
+    path   = "/mnt/volume"
   }
 
 }
@@ -155,7 +163,7 @@ output "ubuntu_container_public_key" {
   - `replicate` (Optional) Will include this volume to a storage replica job.
   - `shared` (Optional) Mark this non-volume mount point as available on all
       nodes.
-  - `size` (Optional) Volume size (only for ZFS storage backed mount points).
+  - `size` (Optional) Volume size (only for volume mount points).
       Can be specified with a unit suffix (e.g. `10G`).
   - `volume` (Required) Volume, device or directory to mount into the
       container.

example/resource_virtual_environment_container.tf

@@ -6,6 +6,13 @@ resource "proxmox_virtual_environment_container" "example_template" {
     size         = 10
   }
 
+  mount_point {
+    // volume mount
+    volume = element(data.proxmox_virtual_environment_datastores.example.datastore_ids, index(data.proxmox_virtual_environment_datastores.example.datastore_ids, "local-lvm"))
+    size   = "4G"
+    path   = "mnt/local"
+  }
+
   initialization {
     dns {
       server = "1.1.1.1"
@@ -63,6 +70,7 @@ resource "proxmox_virtual_environment_container" "example" {
   }
 
   mount_point {
+    // bind mount, requires root@pam
     volume = "/mnt/bindmounts/shared"
     path    = "/shared"
   }

proxmoxtf/resource/container.go

@@ -51,6 +51,7 @@ const (
 	dvResourceVirtualEnvironmentContainerMemorySwap                        = 0
 	dvResourceVirtualEnvironmentContainerMountPointACL                     = false
 	dvResourceVirtualEnvironmentContainerMountPointBackup                  = true
+	dvResourceVirtualEnvironmentContainerMountPointPath                    = ""
 	dvResourceVirtualEnvironmentContainerMountPointQuota                   = false
 	dvResourceVirtualEnvironmentContainerMountPointReadOnly                = false
 	dvResourceVirtualEnvironmentContainerMountPointReplicate               = true
@@ -576,10 +577,17 @@ func Container() *schema.Resource {
 							Type:        schema.TypeString,
 							Description: "Path to the mount point as seen from inside the container",
 							Required:    true,
+							// StateFunc: func(i interface{}) string {
+							// 	// PVE strips leading slashes from the path, so we have to do the same
+							// 	return strings.TrimPrefix(i.(string), "/")
+							// },
+							DiffSuppressFunc: func(k, oldVal, newVal string, d *schema.ResourceData) bool {
+								return "/"+oldVal == newVal
+							},
 						},
 						mkResourceVirtualEnvironmentContainerMountPointQuota: {
 							Type:        schema.TypeBool,
-							Description: "Enable user quotas inside the container (not supported with zfs subvolumes)",
+							Description: "Enable user quotas inside the container (not supported with volume mounts)",
 							Optional:    true,
 							Default:     dvResourceVirtualEnvironmentContainerMountPointQuota,
 						},
@@ -612,6 +620,16 @@ func Container() *schema.Resource {
 							Type:        schema.TypeString,
 							Description: "Volume, device or directory to mount into the container",
 							Required:    true,
+							DiffSuppressFunc: func(k, oldVal, newVal string, d *schema.ResourceData) bool {
+								// For *new* volume mounts PVE returns an actual volume ID which is saved in the stare,
+								// so on reapply the provider will try override it:"
+								//   "local-lvm" -> "local-lvm:vm-101-disk-1"
+								//   "local-lvm:8" -> "local-lvm:vm-101-disk-1"
+								// There is also an option to mount an existing volume, so
+								//   "local-lvm:vm-101-disk-1" -> "local-lvm:vm-101-disk-1"
+								// which is a valid case.
+								return oldVal == newVal || strings.HasPrefix(oldVal, strings.Split(newVal, ":")[0]+":")
+							},
 						},
 					},
 				},
@@ -1330,6 +1348,8 @@ func containerCreateCustom(ctx context.Context, d *schema.ResourceData, m interf
 	mountPoint := d.Get(mkResourceVirtualEnvironmentContainerMountPoint).([]interface{})
 	mountPointArray := make(containers.CustomMountPointArray, 0, len(mountPoint))
 
+	// because of default bool values:
+	//nolint:gosimple
 	for _, mp := range mountPoint {
 		mountPointMap := mp.(map[string]interface{})
 		mountPointObject := containers.CustomMountPoint{}
@@ -1345,13 +1365,34 @@ func containerCreateCustom(ctx context.Context, d *schema.ResourceData, m interf
 		size := mountPointMap[mkResourceVirtualEnvironmentContainerMountPointSize].(string)
 		volume := mountPointMap[mkResourceVirtualEnvironmentContainerMountPointVolume].(string)
 
-		mountPointObject.ACL = &acl
-		mountPointObject.Backup = &backup
-		mountPointObject.MountPoint = path
-		mountPointObject.Quota = &quota
-		mountPointObject.ReadOnly = &readOnly
-		mountPointObject.Replicate = &replicate
-		mountPointObject.Shared = &shared
+		// we have to set only the values that are different from the provider's defaults,
+		if acl != dvResourceVirtualEnvironmentContainerMountPointACL {
+			mountPointObject.ACL = &acl
+		}
+
+		if backup != dvResourceVirtualEnvironmentContainerMountPointBackup {
+			mountPointObject.Backup = &backup
+		}
+
+		if path != dvResourceVirtualEnvironmentContainerMountPointPath {
+			mountPointObject.MountPoint = path
+		}
+
+		if quota != dvResourceVirtualEnvironmentContainerMountPointQuota {
+			mountPointObject.Quota = &quota
+		}
+
+		if readOnly != dvResourceVirtualEnvironmentContainerMountPointReadOnly {
+			mountPointObject.ReadOnly = &readOnly
+		}
+
+		if replicate != dvResourceVirtualEnvironmentContainerMountPointReplicate {
+			mountPointObject.Replicate = &replicate
+		}
+
+		if shared != dvResourceVirtualEnvironmentContainerMountPointShared {
+			mountPointObject.Shared = &shared
+		}
 
 		if len(size) > 0 {
 			var ds types.DiskSize