Merge ~ack/maas:root-dir-snap-overlay into maas:2.7

[Alberto Donato]

LP:1852405 - add overlay for /root directory in the snap, so ssh keys can be used

[Björn Tillenius (bjornt)]

+1. But please file a bug and link it to this MP, and reference the bug in the commit message.

review: Approve

diff --git a/snap/hooks/install b/snap/hooks/install
index 00c1c1a..ba8b96c 100755
--- a/snap/hooks/install
+++ b/snap/hooks/install
@@ -24,6 +24,7 @@ if [ "$user_migration_done" -ne 1 ]; then
     chown -R snap_daemon:snap_daemon "$SNAP_COMMON/log/proxy"
     chown -R snap_daemon:snap_daemon "$SNAP_COMMON/proxy/"{cache,spool}
 fi
+mkdir -p "$SNAP_DATA/root"
 mkdir -p "$SNAP_DATA/preseeds"
 mkdir -p "$SNAP_DATA/bind"
 mkdir -p "$SNAP_DATA/proxy"
diff --git a/snap/local/tree/bin/maas-deb-migrate b/snap/local/tree/bin/maas-deb-migrate
index f29a93f..751989e 100755
--- a/snap/local/tree/bin/maas-deb-migrate
+++ b/snap/local/tree/bin/maas-deb-migrate
@@ -58,6 +58,11 @@ migrate_data() {
     if [ -d /var/lib/maas ]; then
         mv /var/lib/maas "$SNAP_CURRENT/var/lib"
         chown -R root:root "$SNAP_CURRENT/var/lib/maas"
+
+        mkdir -p "$SNAP_CURRENT/root"
+        if [ -d "$SNAP_CURRENT/var/lib/maas/.ssh" ]; then
+           mv "$SNAP_CURRENT/var/lib/maas/.ssh" "$SNAP_CURRENT/root"
+        fi
     fi
     if [ -d /var/spool/maas-proxy ]; then
         mv /var/spool/maas-proxy/* /var/snap/maas/common/proxy/spool/
diff --git a/snap/snapcraft.yaml b/snap/snapcraft.yaml
index b771880..f703023 100644
--- a/snap/snapcraft.yaml
+++ b/snap/snapcraft.yaml
@@ -331,3 +331,5 @@ layout:
     bind: $SNAP/etc/libvirt
   /etc/freeipmi:
     bind: $SNAP/etc/freeipmi
+  /root:
+    bind: $SNAP_DATA/root