Add a preliminary checker to ensure the mount points in /etc/fstab are in the correct order

pleskdistup/actions/common_checks.py

@@ -7,7 +7,7 @@
 import typing
 from abc import abstractmethod
 
-from pleskdistup.common import action, log, packages, php, plesk, version
+from pleskdistup.common import action, log, mounts, packages, php, plesk, version
 
 
 # This action should be considered as deprecated
@@ -677,3 +677,25 @@ def _do_check(self) -> bool:
                     return True
 
         return False
+
+
+class AssertFstabOrderingIsFine(action.CheckAction):
+    FSTAB_PATH: str = "/etc/fstab"
+
+    def __init__(self):
+        self.name = "checking if /etc/fstab is ordered properly"
+        self.description = """The /etc/fstab file entries is not ordered properly.
+\t- {}"""
+
+    def _do_check(self) -> bool:
+        if not os.path.exists(self.FSTAB_PATH):
+            # Might be a problem, but it is not something we checking in scope of this check
+            return True
+
+        misorderings = mounts.get_fstab_configuration_misorderings(self.FSTAB_PATH)
+
+        if len(misorderings) == 0:
+            return True
+
+        self.description = self.description.format("\n\t- ".join([f"Mount point {mount_point} should be placed after {parent_dir}" for parent_dir, mount_point in misorderings]))
+        return False

pleskdistup/common/src/__init__.py

@@ -8,6 +8,7 @@
 from . import mariadb
 from . import leapp_configs
 from . import motd
+from . import mounts
 from . import packages
 from . import php
 from . import plesk

pleskdistup/common/src/mounts.py

@@ -0,0 +1,48 @@
+# Copyright 2023-2024. WebPros International GmbH. All rights reserved.
+import os
+import typing
+
+
+def get_fstab_configuration_misorderings(configpath: str) -> typing.List[typing.Tuple[str, str]]:
+    """
+    Analyzes the fstab configuration file to find misorderings in mount points.
+    This function reads the fstab configuration file specified by `configpath` and checks for any misorderings
+    in the mount points. A misordering is defined as a mount point that appears before its parent directory
+    in the fstab file.
+    Args:
+        configpath (str): The path to the fstab configuration file.
+    Returns:
+        List[Tuple[str, str]]: A list of tuples where each tuple contains a misordered parent directory and
+        its corresponding mount point.
+    Example:
+        >>> get_fstab_configuration_misorderings('/etc/fstab')
+        [('/home', '/home/user'), ('/var', '/var/log')]
+    """
+
+    if not os.path.exists(configpath):
+        return []
+
+    mount_points_order: typing.Dict[str, int] = {}
+    with open(configpath, "r") as f:
+        for iter, line in enumerate(f.readlines()):
+            if line.startswith("#") or line == "\n" or line == "":
+                continue
+            mount_point = line.split()[1]
+            mount_points_order[mount_point] = iter
+
+    misorderings: typing.List[typing.Tuple[str, str]] = []
+    for mount_point in mount_points_order.keys():
+        if mount_point == "/":
+            continue
+
+        parent_dir: str = mount_point
+        root_found: bool = False
+
+        while not root_found:
+            parent_dir = os.path.dirname(parent_dir)
+            if parent_dir in mount_points_order and mount_points_order[parent_dir] > mount_points_order[mount_point]:
+                misorderings.append((parent_dir, mount_point))
+            if parent_dir == "/":
+                root_found = True
+
+    return misorderings

pleskdistup/common/tests/mountstests.py

@@ -0,0 +1,83 @@
+# Copyright 2023-2024. WebPros International GmbH. All rights reserved.
+import unittest
+import tempfile
+
+import src.mounts as mounts
+
+
+class FstabMisorderingTests(unittest.TestCase):
+    def setUp(self):
+        self.test_file_path = tempfile.mktemp()
+
+    def test_no_file(self):
+        self.assertEqual(mounts.get_fstab_configuration_misorderings("noexist.txt"), [])
+
+    def test_empty_file(self):
+        with open(self.test_file_path, "w") as _:
+            pass
+        self.assertEqual(mounts.get_fstab_configuration_misorderings(self.test_file_path), [])
+
+    def test_empty_string(self):
+        with open(self.test_file_path, "w") as f:
+            f.write("")
+        self.assertEqual(mounts.get_fstab_configuration_misorderings(self.test_file_path), [])
+
+    def test_one_mount_point(self):
+        with open(self.test_file_path, "w") as f:
+            f.write("# comment\n")
+            f.write("/dev/sda1 / ext4 defaults 0 1\n")
+        self.assertEqual(mounts.get_fstab_configuration_misorderings(self.test_file_path), [])
+
+    def test_no_misorderings(self):
+        with open(self.test_file_path, "w") as f:
+            f.write("# comment\n")
+            f.write("/dev/sda1 / ext4 defaults 0 1\n")
+            f.write("/dev/sda2 /var ext4 defaults 0 1\n")
+            f.write("proc /proc proc defaults 0 0\n")
+            f.write("devpts /dev/pts devpts gid=5,mode=620 0 0\n")
+            f.write("tmpfs /dev/shm tmpfs defaults 0 0\n")
+        self.assertEqual(mounts.get_fstab_configuration_misorderings(self.test_file_path), [])
+
+    def test_one_misordering(self):
+        with open(self.test_file_path, "w") as f:
+            f.write("# comment\n")
+            f.write("/dev/sda2 /var ext4 defaults 0 1\n")
+            f.write("/dev/sda1 / ext4 defaults 0 1\n")
+            f.write("proc /proc proc defaults 0 0\n")
+            f.write("devpts /dev/pts devpts gid=5,mode=620 0 0\n")
+            f.write("tmpfs /dev/shm tmpfs defaults 0 0\n")
+        self.assertEqual(mounts.get_fstab_configuration_misorderings(self.test_file_path), [("/", "/var")])
+
+    def test_two_misorderings_for_one_parent(self):
+        with open(self.test_file_path, "w") as f:
+            f.write("# comment\n")
+            f.write("/dev/sda2 /var ext4 defaults 0 1\n")
+            f.write("/dev/sda3 /var/log ext4 defaults 0 1\n")
+            f.write("/dev/sda1 / ext4 defaults 0 1\n")
+            f.write("proc /proc proc defaults 0 0\n")
+            f.write("devpts /dev/pts devpts gid=5,mode=620 0 0\n")
+            f.write("tmpfs /dev/shm tmpfs defaults 0 0\n")
+        self.assertEqual(mounts.get_fstab_configuration_misorderings(self.test_file_path), [("/", "/var"), ("/", "/var/log")])
+
+    def test_several_different_misorderings(self):
+        with open(self.test_file_path, "w") as f:
+            f.write("# comment\n")
+            f.write("/dev/sda2 /var ext4 defaults 0 1\n")
+            f.write("/dev/sda1 / ext4 defaults 0 1\n")
+            f.write("/dev/sda5 /home/test ext4 defaults 0 1\n")
+            f.write("/dev/sda4 /home ext4 defaults 0 1\n")
+            f.write("proc /proc proc defaults 0 0\n")
+            f.write("devpts /dev/pts devpts gid=5,mode=620 0 0\n")
+            f.write("tmpfs /dev/shm tmpfs defaults 0 0\n")
+        self.assertEqual(mounts.get_fstab_configuration_misorderings(self.test_file_path), [("/", "/var"), ("/home", "/home/test")])
+
+    def test_file_without_root(self):
+        with open(self.test_file_path, "w") as f:
+            f.write("# comment\n")
+            f.write("/dev/sda2 /var ext4 defaults 0 1\n")
+            f.write("/dev/sda5 /home/test ext4 defaults 0 1\n")
+            f.write("/dev/sda4 /home ext4 defaults 0 1\n")
+            f.write("proc /proc proc defaults 0 0\n")
+            f.write("devpts /dev/pts devpts gid=5,mode=620 0 0\n")
+            f.write("tmpfs /dev/shm tmpfs defaults 0 0\n")
+        self.assertEqual(mounts.get_fstab_configuration_misorderings(self.test_file_path), [("/home", "/home/test")])