Merge ~afreiberger/charm-juju-lxd:init_with_dir_storage into charm-juju-lxd:master

[Drew Freiberger]

[Drew Freiberger (afreiberger)]

This is untested. we should add this as a new charm to yobuko, and rebuild one of the boxes under this charm to test dir-based lxd deployment. Charmlab3/ewah is free for this from my perspective.

This change is necessary to work around https://github.com/conjure-up/conjure-up/issues/1430 where kubernetes-worker won't run kubelet service under a zfs/btrfs backed lxd.

[Chris Sanders (chris.sanders)]

lgtm, one day testing for this charm would be nice, but I wouldn't block on a complete port of testing just to land this change in the charm lab.

review: Approve

diff --git a/config.yaml b/config.yaml
index 698900c..8db0ec4 100644
--- a/config.yaml
+++ b/config.yaml
@@ -3,3 +3,7 @@ options:
     type: string
     default: "bootstack-squad"
     description: user group that should have members added to local lxd group
+  use-zfs:
+    type: boolean
+    default: false
+    description: Whether to use zfs backend for LXD storage - default is dir
diff --git a/reactive/juju_lxd.py b/reactive/juju_lxd.py
index c48a917..c6c83ff 100644
--- a/reactive/juju_lxd.py
+++ b/reactive/juju_lxd.py
@@ -78,12 +78,19 @@ def check_reconfig():
 def lxd_init():
     # f = open("files/lxd-init-preseed.yaml", "r")
     # subprocess.call(['lxd', 'init', '--preseed'], stdin=f)
+    config = hookenv.config()
+    use_zfs = config.get('use-zfs')
+
     subprocess.call(['apt-get', '-t', 'xenial-backports', 'install', '-y',
                      'lxd', 'lxd-client'])
 
-    subprocess.call(['lxd', 'init', '--auto', '--storage-backend', 'zfs',
-                     '--storage-pool', 'lxd', '--storage-create-loop', '100'])
-    subprocess.call(['zpool', 'set', 'autoexpand=on', 'lxd'])
+    if use_zfs:
+        subprocess.call(['lxd', 'init', '--auto', '--storage-backend', 'zfs',
+                         '--storage-pool', 'lxd', '--storage-create-loop', '100'])
+        subprocess.call(['zpool', 'set', 'autoexpand=on', 'lxd'])
+    else:
+        subprocess.call(['lxd', 'init', '--auto', '--storage-backend', 'dir'])
+
 
     subprocess.call(['lxc', 'network', 'delete', 'lxdbr0'])
     subprocess.call(['lxc', 'network', 'create', 'lxdbr0',