Navidrome: self-heal the connection instead of latching disconnected (jimmydotcom)

A transient ping failure (network blip, Navidrome busy mid-scan) makes
_setup_client null out the configured creds, and _connection_attempted then
latches the client "disconnected" — so is_connected() returned False forever until
the user hit the manual Test button to re-read config. That's the reported
"disconnects every 5-10 min, reconnects instantly on Test."

Fix: ensure_connection no longer latches on a failed attempt — once a short
throttle (_RECONNECT_THROTTLE_S = 20s) elapses it re-attempts, and is_connected()
triggers that retry whenever it's currently disconnected. So a blip recovers on its
own within the next status check, no manual reconnect. The throttle prevents ping
storms when Navidrome is genuinely down.

Tests: transient failure self-heals after the throttle (and doesn't re-ping within
it); a connected client never re-pings; first connect attempts once. 115 navidrome/
media-server tests green.

core/navidrome_client.py

@@ -1,6 +1,7 @@
 import requests
 import hashlib
 import secrets
+import time
 from typing import List, Optional, Dict, Any
 from datetime import datetime
 from urllib.parse import urlencode
@@ -161,6 +162,7 @@ class NavidromeClient(MediaServerClient):
         self.music_folder_id: Optional[str] = None
         self._connection_attempted = False
         self._is_connecting = False
+        self._last_connect_attempt = 0.0   # monotonic time of the last connect try
 
         # Cache for performance
         self._artist_cache = {}
@@ -245,15 +247,32 @@ class NavidromeClient(MediaServerClient):
             logger.error(f"Error setting music folder: {e}")
             return False
 
+    # A failed connect used to latch the client "disconnected" until the user hit
+    # the manual Test button (a transient ping failure nukes the creds in
+    # _setup_client). Re-attempt at most this often so it self-heals on its own.
+    _RECONNECT_THROTTLE_S = 20.0
+
     def ensure_connection(self) -> bool:
-        """Ensure connection to Navidrome server with lazy initialization."""
-        if self._connection_attempted:
-            return self.base_url is not None and self.username is not None
+        """Ensure connection to Navidrome with lazy init + self-healing retry.
+
+        Already connected → return True. A prior FAILED attempt no longer latches
+        forever: once _RECONNECT_THROTTLE_S has elapsed it re-attempts, so a
+        transient ping failure (network blip, Navidrome busy mid-scan) recovers by
+        itself instead of needing the manual "Test" reconnect."""
+        if self.base_url is not None and self.username is not None:
+            return True
 
         if self._is_connecting:
             return False
 
+        # Disconnected but attempted recently → don't hammer; let it heal on the
+        # next check past the throttle window.
+        if self._connection_attempted and \
+                (time.monotonic() - self._last_connect_attempt) < self._RECONNECT_THROTTLE_S:
+            return False
+
         self._is_connecting = True
+        self._last_connect_attempt = time.monotonic()
         try:
             self._setup_client()
             return self.base_url is not None and self.username is not None
@@ -462,10 +481,11 @@ class NavidromeClient(MediaServerClient):
             return None
 
     def is_connected(self) -> bool:
-        """Check if connected to Navidrome server"""
-        if not self._connection_attempted:
-            if not self._is_connecting:
-                self.ensure_connection()
+        """Connected = configured + last connect OK. When NOT connected, trigger a
+        (throttled) reconnect attempt so the status self-heals instead of staying
+        latched disconnected until a manual Test."""
+        if not (self.base_url and self.username and self.password) and not self._is_connecting:
+            self.ensure_connection()
         return (self.base_url is not None and
                 self.username is not None and
                 self.password is not None)

tests/test_navidrome_self_heal.py

@@ -0,0 +1,54 @@
+"""Navidrome connection self-heals after a transient ping failure (jimmydotcom).
+
+A failed ping nukes the creds in _setup_client; previously _connection_attempted
+latched the client 'disconnected' until a manual Test. Now is_connected re-attempts
+(throttled) so a blip recovers on its own."""
+
+from __future__ import annotations
+
+from core.navidrome_client import NavidromeClient
+
+
+def test_self_heals_after_transient_failure(monkeypatch):
+    c = NavidromeClient()
+    calls = {'n': 0}
+
+    def fake_setup():
+        calls['n'] += 1
+        if calls['n'] == 1:                      # transient failure nukes creds
+            c.base_url = c.username = c.password = None
+        else:                                     # blip passed → connects
+            c.base_url, c.username, c.password = 'http://nd:4533', 'u', 'p'
+    monkeypatch.setattr(c, '_setup_client', fake_setup)
+
+    assert c.is_connected() is False             # first attempt fails
+    assert calls['n'] == 1
+
+    assert c.is_connected() is False             # immediate recheck: throttled
+    assert calls['n'] == 1                       # did NOT re-ping (no storm)
+
+    c._last_connect_attempt -= (c._RECONNECT_THROTTLE_S + 1)   # throttle window elapses
+    assert c.is_connected() is True              # re-attempts → recovers itself
+    assert calls['n'] == 2                       # no manual reconnect was needed
+
+
+def test_connected_client_does_not_reattempt(monkeypatch):
+    c = NavidromeClient()
+    c.base_url, c.username, c.password = 'http://nd', 'u', 'p'
+    c._connection_attempted = True
+    calls = {'n': 0}
+    monkeypatch.setattr(c, '_setup_client', lambda: calls.__setitem__('n', calls['n'] + 1))
+    assert c.is_connected() is True
+    assert calls['n'] == 0                        # already connected → never re-pings
+
+
+def test_first_connect_attempts_once(monkeypatch):
+    c = NavidromeClient()
+    calls = {'n': 0}
+
+    def fake_setup():
+        calls['n'] += 1
+        c.base_url, c.username, c.password = 'http://nd', 'u', 'p'
+    monkeypatch.setattr(c, '_setup_client', fake_setup)
+    assert c.is_connected() is True
+    assert calls['n'] == 1