storage/volumes: support nesting

2 files changed, 20 insertions, 6 deletions

diff --git a/roles/storage/zfs/volume/defaults/main.yml b/roles/storage/zfs/volume/defaults/main.yml
index b4df433e..bb1c0c6d 100644
--- a/roles/storage/zfs/volume/defaults/main.yml
+++ b/roles/storage/zfs/volume/defaults/main.yml
@@ -1,5 +1,8 @@
 ---
 # zfs_volume:
+#   parent:
+#     type: zfs
+#     ...
 #   pool: tank
 #   name: foo/bar
 #   properties:
diff --git a/roles/storage/zfs/volume/tasks/main.yml b/roles/storage/zfs/volume/tasks/main.yml
index 1bd198bb..0dc0e82d 100644
--- a/roles/storage/zfs/volume/tasks/main.yml
+++ b/roles/storage/zfs/volume/tasks/main.yml
@@ -1,18 +1,29 @@
 ---
+  ## TODO: implement recursive nesting
+- name: check volume parent
+  when: "'parent' in zfs_volume"
+  assert:
+    msg: "the volume parent must be of type zfs and must not have a parent"
+    that:
+    - zfs_volume.parent.type == 'zfs'
+    - "'parent' not in zfs_volume.parent"
+
 - name: create zfs dataset
   zfs:
-    name: "{{ zfs_volume.pool }}/{{ zfs_volume.name }}"
+    name: "{{ ('parent' in zfs_volume) | ternary((zfs_volume.parent.pool | default(''))~'/'~(zfs_volume.parent.name | default('')), zfs_volume.pool) }}/{{ zfs_volume.name }}"
     extra_zfs_properties: "{{ zfs_volume.properties | dehumanize_zfs_properties | default(omit) }}"
     state: present
 
+- name: compute derivated mountpoint
+  set_fact:
+    zfs_volume_mountpoint: "{{ (zfs_pools[zfs_volume.parent.pool | default(zfs_volume.pool)].mountpoint, ('parent' in zfs_volume) | ternary((zfs_volume.parent.name | default('')), ''), zfs_volume.name) | path_join }}"
+
 - name: bind mount filesystem
-  vars:
-    zfs_mountpoint: "{{ (zfs_pools[zfs_volume.pool].mountpoint, zfs_volume.name) | path_join }}"
   when:
   - "'dest' in zfs_volume"
-  - zfs_volume.dest != zfs_mountpoint
+  - zfs_volume.dest != zfs_volume_mountpoint
   mount:
-    src: "{{ zfs_mountpoint }}"
+    src: "{{ zfs_volume_mountpoint }}"
     path: "{{ zfs_volume.dest }}"
     fstype: none
     opts: bind,x-systemd.automount,nofail
@@ -21,7 +32,7 @@
 - name: set volume owner/group and mode
   file:
     state: directory
-    path: "{{ zfs_volume.dest | default((zfs_pools[zfs_volume.pool].mountpoint, zfs_volume.name) | path_join) }}"
+    path: "{{ zfs_volume.dest | default(zfs_volume_mountpoint) }}"
     mode: "{{ zfs_volume.mode | default(omit) }}"
     owner: "{{ zfs_volume.owner | default(omit) }}"
     group: "{{ zfs_volume.group | default(omit) }}"