bundles/backup-server: support raid0-ing multiple raidz

bundles/backup-server/metadata.py

@@ -1,3 +1,5 @@
+from bundlewrap.exceptions import BundleError
+
 defaults = {
     'backup-server': {
         'my_ssh_port': 22,
@@ -69,25 +71,51 @@ def zfs_pool(metadata):
         return {}
 
     crypt_devices = {}
-    pool_devices = set()
     unlock_actions = set()
 
-    for number, (device, passphrase) in enumerate(sorted(metadata.get('backup-server/encrypted-devices', {}).items())):
+    devices = metadata.get('backup-server/encrypted-devices')
-        crypt_devices[device] = {
-            'dm-name': f'backup{number}',
-            'passphrase': passphrase,
-        }
-        pool_devices.add(f'/dev/mapper/backup{number}')
-        unlock_actions.add(f'action:dm-crypt_open_backup{number}')
 
-    pool_opts = {
+    # TODO remove this once we have migrated all systems
-        'devices': pool_devices,
+    if isinstance(devices, dict):
-    }
+        pool_devices = set()
 
-    if len(pool_devices) > 2:
+        for number, (device, passphrase) in enumerate(sorted(devices.items())):
-        pool_opts['type'] = 'raidz'
+            crypt_devices[device] = {
-    elif len(pool_devices) > 1:
+                'dm-name': f'backup{number}',
-        pool_opts['type'] = 'mirror'
+                'passphrase': passphrase,
+            }
+            pool_devices.add(f'/dev/mapper/backup{number}')
+            unlock_actions.add(f'action:dm-crypt_open_backup{number}')
+
+        pool_config = [{
+            'devices': pool_devices,
+        }]
+
+        if len(pool_devices) > 2:
+            pool_config[0]['type'] = 'raidz'
+        elif len(pool_devices) > 1:
+            pool_config[0]['type'] = 'mirror'
+
+    elif isinstance(devices, list):
+        pool_config = []
+
+        for idx, intended_pool in enumerate(devices):
+            pool_devices = set()
+
+            for number, (device, passphrase) in enumerate(sorted(intended_pool.items())):
+                crypt_devices[device] = {
+                    'dm-name': f'backup{idx}-{number}',
+                    'passphrase': passphrase,
+                }
+                pool_devices.add(f'/dev/mapper/backup{idx}-{number}')
+                unlock_actions.add(f'action:dm-crypt_open_backup{idx}-{number}')
+
+            pool_config.append({
+                'devices': pool_devices,
+                'type': 'raidz',
+            })
+    else:
+        raise BundleError(f'{node.name}: unsupported configuration for backup-server/encrypted-devices')
 
     return {
         'backup-server': {
@@ -100,9 +128,8 @@ def zfs_pool(metadata):
             'pools': {
                 'backups': {
                     'when_creating': {
-                        'config': [
+                        'config': pool_config,
-                            pool_opts,
+                        **metadata.get('backup-server/zpool_create_options', {}),
-                        ],
                     },
                     'needs': unlock_actions,
                     # That's a bit hacky. We do it this way to auto-import