fix(monitor): refresh the VM/LXC modal after edits made outside the Monitor

AppImage/scripts/tests/test_vm_conf_cache.py

@@ -0,0 +1,60 @@
+"""The VM/LXC modal caches notice a .conf edited outside the Monitor."""
+import ast
+from pathlib import Path
+import threading
+import time
+from types import SimpleNamespace
+import unittest
+
+SERVER = Path(__file__).resolve().parents[1] / 'flask_server.py'
+NAMES = ('_vm_cache_get', '_vm_cache_put', '_vm_conf_signature', '_vm_conf_cache_get', '_vm_conf_cache_put')
+
+
+class ConfAwareCacheTests(unittest.TestCase):
+    def setUp(self):
+        tree = ast.parse(SERVER.read_text(encoding='utf-8'))
+        nodes = [n for n in tree.body if isinstance(n, ast.FunctionDef) and n.name in NAMES]
+        self.assertEqual(sorted(n.name for n in nodes), sorted(NAMES))
+        self.files = {'/etc/pve/lxc/111.conf': (1, 300)}
+
+        def stat(path):
+            if path not in self.files:
+                raise OSError(path)
+            mtime, size = self.files[path]
+            return SimpleNamespace(st_mtime_ns=mtime, st_size=size)
+
+        self.scope = {'os': SimpleNamespace(stat=stat), 'time': time, '_vm_modal_cache_lock': threading.Lock(),
+                      '_vm_conf_built': {}}
+        exec(compile(ast.Module(body=nodes, type_ignores=[]), str(SERVER), 'exec'), self.scope)
+        self.cache = {}
+
+    def build(self, value):
+        signature = self.scope['_vm_conf_signature'](111)
+        self.scope['_vm_conf_cache_put'](self.cache, 'details', 111, value, signature)
+
+    def get(self):
+        return self.scope['_vm_conf_cache_get'](self.cache, 'details', 111, 10 ** 9)
+
+    def test_unchanged_conf_serves_the_cache(self):
+        self.build({'onboot': 1})
+        self.assertEqual(self.get(), {'onboot': 1})
+
+    def test_conf_edited_outside_the_monitor_drops_the_entry(self):
+        self.build({'onboot': 1})
+        self.files['/etc/pve/lxc/111.conf'] = (2, 300)   # `pct set 111 --onboot 0`
+        self.assertIsNone(self.get())
+        self.build({'onboot': 0})
+        self.assertEqual(self.get(), {'onboot': 0})
+
+    def test_entry_without_a_recorded_conf_is_rebuilt(self):
+        self.scope['_vm_cache_put'](self.cache, 111, {'old': True})
+        self.assertIsNone(self.get())
+
+    def test_vm_conf_path_and_missing_guest(self):
+        self.files = {'/etc/pve/qemu-server/200.conf': (5, 10)}
+        self.assertEqual(self.scope['_vm_conf_signature'](200), (5, 10))
+        self.assertIsNone(self.scope['_vm_conf_signature'](999))
+
+
+if __name__ == '__main__':
+    unittest.main()