backup_clouds-NFS adapter (#1055)

* backup_clouds-NFS adapter - initial version

* fix timeout issue for scheduled backup, improve error handling and logging

* Update packages/main.py

Hallo Lena,
das glaube ich einfach mal :-) 
Ich werde es testen wenn es im master ist.

Co-authored-by: LKuemmel <76958050+LKuemmel@users.noreply.github.com>

---------

Co-authored-by: LKuemmel <76958050+LKuemmel@users.noreply.github.com>

packages/modules/backup_clouds/nfs/backup_cloud.py

@@ -0,0 +1,73 @@
+#!/usr/bin/env python3
+import logging
+from subprocess import Popen, PIPE, CalledProcessError, run
+from pathlib import Path
+
+from modules.backup_clouds.nfs.config import NfsBackupCloud, NfsBackupCloudConfiguration
+from modules.common.abstract_device import DeviceDescriptor
+from modules.common.configurable_backup_cloud import ConfigurableBackupCloud
+
+log = logging.getLogger(__name__)
+nfs_mount = '/mnt/nfs_mount'
+
+
+# run command as subprocess with timeout, some exception handling and logging
+def _run(_cmd: str, _timeout: float, _shell: bool) -> bool:
+    log.info('backup-nfs: cmd ' + _cmd + ': starting')
+    try:
+        p = run([_cmd], timeout=_timeout, stdout=PIPE, stderr=PIPE, shell=_shell)
+        p.check_returncode()
+    except CalledProcessError as e:
+        log.exception('backup-nfs: cmd ' + _cmd + ', Faii: errorcode: '
+                      + str(e.returncode) + ', stderr: ' + p.stderr.decode('utf-8'))
+        raise e
+        return False
+    if p.stdout.decode('utf-8') is not None and p.stdout.decode('utf-8') != '':
+        log.info('backup-nfs: cmd ' + _cmd + ': Success, stdout: [' + p.stdout.decode('utf-8') + ']')
+    else:
+        log.info('backup-nfs: cmd ' + _cmd + ': Success')
+    return True
+
+
+def upload_backup(config: NfsBackupCloudConfiguration, backup_filename: str, backup_file: bytes) -> None:
+    nfs_share = config.nfs_share
+
+    # create nfs mount folder if not existent
+    p = Path(nfs_mount)
+    if p.is_dir():
+        log.warn('nfs mount folder ' + nfs_mount + ' exists - reuse it')
+        rc = True
+    else:
+        rc = _run('sudo mkdir ' + nfs_mount, 5, True)
+
+    # check if nfs is mounted already
+    if rc:
+        cmd = 'mount | grep "' + nfs_share + '" | wc -l'
+        p = Popen(cmd, shell=True, stdout=PIPE, stderr=PIPE)
+        stdout, stderr = p.communicate()
+        if int(stdout) != 0:
+            log.warn('nfs share seems tio be mounted - reuse it')
+        else:
+            rc = _run('sudo mount -t nfs ' + nfs_share + ' ' + nfs_mount, 10, True)
+
+    # copy backup file to nfs share
+    if rc:
+        rc = _run('sudo cp /var/www/html/openWB/data/backup/' + backup_filename +
+                  ' ' + nfs_mount + '/' + backup_filename, 5, True)
+
+    # umount nfs share
+    if rc:
+        rc = _run('sudo umount ' + nfs_mount, 5, True)
+
+    # remove mount point
+    if rc:
+        rc = _run('sudo rmdir ' + nfs_mount, 5, True)
+
+
+def create_backup_cloud(config: NfsBackupCloud):
+    def updater(backup_filename: str, backup_file: bytes):
+        upload_backup(config.configuration, backup_filename, backup_file)
+    return ConfigurableBackupCloud(config=config, component_updater=updater)
+
+
+device_descriptor = DeviceDescriptor(configuration_factory=NfsBackupCloud)

packages/modules/backup_clouds/nfs/config.py

@@ -0,0 +1,16 @@
+from typing import Optional
+
+
+class NfsBackupCloudConfiguration:
+    def __init__(self, nfs_share: Optional[str] = None):
+        self.nfs_share = nfs_share
+
+
+class NfsBackupCloud:
+    def __init__(self,
+                 name: str = "Nfs",
+                 type: str = "nfs",
+                 configuration: NfsBackupCloudConfiguration = None) -> None:
+        self.name = name
+        self.type = type
+        self.configuration = configuration or NfsBackupCloudConfiguration()