Adds mount_remote_dir

Adds the mount_remote_dir method to the synchroniser, this allows to
mount the remote directory in order to access it with the generated
links.
Also adds the background parameter to the documentation of update_links

src/unisync/synchroniser.py

@@ -7,6 +7,8 @@ import sys
 import time
 import logging
 
+from pathlib import Path
+
 logger = logging.getLogger(__name__)
 
 class Synchroniser:
@@ -141,7 +143,7 @@ class Synchroniser:
         First calls cleanlinks to remove deadlinks and empty directories.
         Then calls lndir to create the new links.
         Args:
-        - 
+        - background: controls if the update is done in the background or waited for
         """
 
         link_update_script = (f"cd {self.remote_dir}/links && "
@@ -168,3 +170,21 @@ class Synchroniser:
             link_update_process.wait()
             print("Done")
 
+    def mount_remote_dir(self):
+        """
+        Mount the remote directory to make the local links work.
+        This is achieved using sshfs.
+        Raise:
+        - subprocess.CalledProcessError: An error occured with sshfs
+        """
+        command = [
+                "/usr/bin/sshfs",
+                "-o", "ControlPath={self.control_path}",
+                "-o", "ServerAliveInterval=15",
+                "-p", str(self.remote_port),
+                f"{self.remote_user}@{self.remote_ip}:{self.remote_dir}/.data",
+                # Get the absolute path to the correct .data directory resolving symlinks
+                str(Path(f"{self.local}/../.data").resolve())
+                ]
+        completed_process = subprocess.run(command)
+        completed_process.check_returncode()