Merge pull request #9 from Jip-Hop/delete-cmd

Delete and list jails

jlmkr.py

@@ -13,6 +13,7 @@ import shutil
 import stat
 import subprocess
 import sys
+import time
 import urllib.request
 
 from inspect import cleandoc
@@ -59,12 +60,16 @@ def fail(*args, **kwargs):
     sys.exit(1)
 
 
+def get_jail_path(jail_name):
+    return os.path.join(JAILS_DIR_PATH, jail_name)
+
+
 def start_jail(jail_name):
     """
     Start jail with given name.
     """
 
-    jail_path = os.path.join(JAILS_DIR_PATH, jail_name)
+    jail_path = get_jail_path(jail_name)
     jail_config_path = os.path.join(jail_path, JAIL_CONFIG_NAME)
 
     config = configparser.ConfigParser()
@@ -188,7 +193,7 @@ def start_jail(jail_name):
 
     print(dedent(f"""
         Starting jail with the following command:
-        
+
         {shlex.join(cmd)}
 
         Starting jail with name: {jail_name}
@@ -284,6 +289,38 @@ def get_mount_point(path):
     return path
 
 
+def check_jail_name_valid(jail_name, warn=True):
+    """
+    Return True if jail name matches the required format.
+    """
+    if re.match(r"^[.a-zA-Z0-9-]{1,64}$", jail_name) and not jail_name.startswith(".") and ".." not in jail_name:
+        return True
+
+    if warn:
+        eprint(dedent(f"""
+            {YELLOW}{BOLD}WARNING: INVALID NAME{NORMAL}
+
+            A valid name consists of:
+            - allowed characters (alphanumeric, dash, dot)
+            - no leading or trailing dots
+            - no sequences of multiple dots
+            - max 64 characters"""))
+    return False
+
+
+def check_jail_name_available(jail_name, warn=True):
+    """
+    Return True if jail name is not yet taken.
+    """
+    if not os.path.exists(get_jail_path(jail_name)):
+        return True
+
+    if warn:
+        print()
+        eprint("A jail with this name already exists.")
+    return False
+
+
 def create_jail(jail_name):
     """
     Create jail with given name.
@@ -365,29 +402,14 @@ def create_jail(jail_name):
 
         release = input("Release: ")
 
-    jail_path = None
-
-    while jail_path == None:
+    while True:
         print()
         jail_name = input_with_default("Enter jail name: ", jail_name).strip()
-        if not re.match(r"^[.a-zA-Z0-9-]{1,64}$", jail_name) or jail_name.startswith(".") or ".." in jail_name:
-            eprint(dedent(f"""
+        if check_jail_name_valid(jail_name):
+            if check_jail_name_available(jail_name):
+                break
 
-                {YELLOW}{BOLD}WARNING: INVALID NAME{NORMAL}
-
-                A valid name consists of:
-                - allowed characters (alphanumeric, dash, dot)
-                - no leading or trailing dots
-                - no sequences of multiple dots
-                - max 64 characters
-
-            """))
-        else:
-            jail_path = os.path.join(JAILS_DIR_PATH, jail_name)
-            if os.path.exists(jail_path):
-                print()
-                eprint("A jail with this name already exists.")
-                jail_path = None
+    jail_path = get_jail_path(jail_name)
 
     # Cleanup in except, but only once the jail_path is final
     # Otherwise we may cleanup the wrong directory
@@ -412,7 +434,7 @@ def create_jail(jail_name):
 
         print(dedent(f"""
             {YELLOW}{BOLD}WARNING: CHECK SYNTAX{NORMAL}
-        
+
             You may pass additional flags to systemd-nspawn.
             With incorrect flags the jail may not start.
             It is possible to correct/add/remove flags post-install.
@@ -500,7 +522,7 @@ def create_jail(jail_name):
                 os.path.join(jail_rootfs_path, 'sbin/init'))) != "systemd":
             print(dedent(f"""
                 {YELLOW}{BOLD}WARNING: DISTRO NOT SUPPORTED{NORMAL}
-                
+
                 Chosen distro appears not to use systemd...
 
                 You probably will not get a shell with:
@@ -616,6 +638,44 @@ def create_jail(jail_name):
         start_jail(jail_name)
 
 
+def delete_jail(jail_name):
+    """
+    Delete jail with given name.
+    """
+
+    if check_jail_name_valid(jail_name):
+        if check_jail_name_available(jail_name, False):
+            eprint(f"A jail with name {jail_name} does not exist.")
+        else:
+            check = input(f'\nCAUTION: Type "{jail_name}" to confirm jail deletion!\n\n') or ""
+            if check == jail_name:
+                jail_path = get_jail_path(jail_name)
+                print(f"\nTrying to stop {jail_name} if it was running...")
+                subprocess.run(['machinectl', 'stop', jail_name])
+                # Need to sleep since deleting immediately after stop causes problems...
+                time.sleep(1)
+                print(f"Cleaning up: {jail_path}")
+                shutil.rmtree(jail_path)
+            else:
+                eprint("Wrong name, nothing happened.")
+
+def list_jails():
+    """
+    List all available and running jails.
+    """
+
+    jails = next(os.walk('jails'))[1]
+
+    print("Available jails:\n")
+    if not len(jails):
+        print("No jails.")
+    else:
+        for jail in jails:
+            print(f"{jail}")
+
+    print("\nCurrently running:\n")
+    os.system(f"machinectl list")
+
 def main():
     if os.stat(__file__).st_uid != 0:
         fail("This script should be owned by the root user...")
@@ -627,10 +687,16 @@ def main():
     subparsers = parser.add_subparsers(title='commands', dest='subcommand')
 
     create_parser = subparsers.add_parser(name='create', epilog=DISCLAIMER)
-    create_parser.add_argument('name', nargs='?', help='name of the jail')
+    create_parser.add_argument(
+        'name', nargs='?', help='name of the jail to create')
 
     start_parser = subparsers.add_parser(name='start', epilog=DISCLAIMER)
-    start_parser.add_argument('name', help='name of the jail')
+    start_parser.add_argument('name', help='name of the jail to start')
+
+    start_parser = subparsers.add_parser(name='delete', epilog=DISCLAIMER)
+    start_parser.add_argument('name', help='name of the jail to delete')
+
+    start_parser = subparsers.add_parser(name='list', epilog=DISCLAIMER)
 
     parser.usage = f"{parser.format_usage()[7:]}{create_parser.format_usage()}{start_parser.format_usage()}"
 
@@ -653,6 +719,12 @@ def main():
     elif args.subcommand == 'create':
         create_jail(args.name)
 
+    elif args.subcommand == 'delete':
+        delete_jail(args.name)
+
+    elif args.subcommand == 'list':
+        list_jails()
+
     elif args.subcommand:
         parser.print_usage()