fixes and improvements

backend/src/media_library_viewer_api/dependencies.py

@@ -1,17 +1,23 @@
 """Dependency injection for FastAPI.
 
-Provides singleton-like access to SSH and Jellyfin clients via FastAPI's
-dependency system. Uses lru_cache so connections are reused across requests.
+Provides access to machine-specific Jellyfin/SSH clients via FastAPI's request
+context. The selected machine can be chosen with a ``machine_id`` query
+parameter; otherwise the backend falls back to the first enabled machine that
+matches the requested service.
 """
 
 from __future__ import annotations
 
 import logging
 from functools import lru_cache
+from typing import Any
+
+from fastapi import Request
 
 from media_library_viewer_api.clients.jellyfin import JellyfinClient
 from media_library_viewer_api.clients.jellyseerr import JellyseerrClient
 from media_library_viewer_api.clients.ssh import RemoteSSHClient
+from media_library_viewer_api.services.known_hosts import ensure_known_host
 from media_library_viewer_api.config import get_settings
 from media_library_viewer_api.services.mail_queue import MailQueue, get_mail_queue as _get_mail_queue
 from media_library_viewer_api.services.monitoring_poller import (
@@ -23,17 +29,100 @@ from media_library_viewer_api.services.settings_store import SettingsStore, get_
 logger = logging.getLogger(__name__)
 
 
-@lru_cache
-def get_jellyfin_client() -> JellyfinClient:
-    """Return a cached Jellyfin client."""
+def _request_machine_id(request: Request | None) -> str | None:
+    if request is None:
+        return None
+    machine_id = request.query_params.get("machine_id")
+    return machine_id or None
+
+
+@lru_cache(maxsize=32)
+def _jellyfin_client_for(cache_key: tuple[str, str, str]) -> JellyfinClient:
+    machine_id, url, api_key = cache_key
+    logger.info("Creating Jellyfin client machine_id=%s url=%s", machine_id or "<default>", url.rstrip("/") or "<unset>")
+    return JellyfinClient(url, api_key)
+
+
+@lru_cache(maxsize=32)
+def _jellyseerr_client_for(cache_key: tuple[str, str]) -> JellyseerrClient | None:
+    machine_id, url = cache_key
+    if not url:
+        return None
+    settings = get_settings_store().get_machine_config(machine_id) if machine_id else None
+    api_key = (settings or {}).get("jellyseerr_api_key") if settings else ""
+    if not api_key:
+        return None
+    logger.info("Creating Jellyseerr client machine_id=%s url=%s", machine_id or "<default>", url.rstrip("/") or "<unset>")
+    return JellyseerrClient(url, api_key)
+
+
+@lru_cache(maxsize=32)
+def _ssh_client_for(cache_key: tuple[str, str, str, int, str, str | None, str | None]) -> RemoteSSHClient:
+    machine_id, host, username, port, key_filename, password, known_hosts_path = cache_key
+    logger.info(
+        "Creating SSH client machine_id=%s host=%s user=%s port=%s key=%s password=%s",
+        machine_id or "<default>",
+        host or "<unset>",
+        username or "<unset>",
+        port,
+        key_filename or "<unset>",
+        "set" if password else "missing",
+    )
+    client = RemoteSSHClient(
+        host=host,
+        username=username,
+        port=port,
+        key_filename=key_filename or None,
+        password=password or None,
+        known_hosts_path=known_hosts_path or None,
+    )
+    try:
+        client.connect()
+    except Exception:
+        logger.exception("Failed to establish SSH connection to %s", host or "<unset>")
+        raise
+    return client
+
+
+def _resolve_machine(service: str, request: Request | None = None) -> dict[str, Any] | None:
+    store = get_settings_store()
+    machine_id = _request_machine_id(request)
+    if machine_id:
+        machine = store.get_machine(machine_id)
+        if machine and (service in machine.get("services", []) or service == "ssh"):
+            return machine
+        return machine
+    if service == "jellyfin":
+        machines = store.list_machines_for_service("jellyfin")
+    elif service == "jellyseerr":
+        machines = [m for m in store.list_machines_for_service("jellyfin") if m.get("jellyseerr_url")]
+    elif service == "ssh":
+        machines = store.list_machines_for_service("files") or store.list_machines_for_service("monitoring")
+    else:
+        machines = store.list_machines_for_service(service)
+    return machines[0] if machines else None
+
+
+def get_jellyfin_client(request: Request = None) -> JellyfinClient:
+    """Return a Jellyfin client for the selected machine or legacy env fallback."""
+    machine = get_settings_store().get_machine_config(_request_machine_id(request)) or _resolve_machine("jellyfin", request)
+    if machine and machine.get("jellyfin_url") and machine.get("jellyfin_api_key"):
+        cache_key = (machine["id"], machine["jellyfin_url"], machine.get("jellyfin_api_key") or "")
+        return _jellyfin_client_for(cache_key)
+
     settings = get_settings()
-    logger.info("Creating Jellyfin client for %s", settings.jellyfin_url.rstrip("/") or "<unset>")
-    return JellyfinClient(settings.jellyfin_url, settings.jellyfin_api_key)
+    if not settings.jellyfin_url or not settings.jellyfin_api_key:
+        raise RuntimeError("No Jellyfin machine is configured and JELLYFIN_URL/API_KEY are not set")
+    logger.info("Falling back to legacy Jellyfin env settings")
+    return _jellyfin_client_for(("legacy", settings.jellyfin_url, settings.jellyfin_api_key))
 
 
-@lru_cache
-def get_jellyseerr_client() -> JellyseerrClient | None:
+def get_jellyseerr_client(request: Request = None) -> JellyseerrClient | None:
     """Return a cached Jellyseerr client when configured, otherwise None."""
+    machine = get_settings_store().get_machine_config(_request_machine_id(request)) or _resolve_machine("jellyseerr", request)
+    if machine and machine.get("jellyseerr_url") and machine.get("jellyseerr_api_key"):
+        return JellyseerrClient(machine["jellyseerr_url"], machine.get("jellyseerr_api_key") or "")
+
     settings = get_settings()
     if not settings.jellyseerr_url or not settings.jellyseerr_api_key:
         logger.info(
@@ -42,16 +131,30 @@ def get_jellyseerr_client() -> JellyseerrClient | None:
             "set" if settings.jellyseerr_api_key else "missing",
         )
         return None
-    logger.info("Creating Jellyseerr client for %s", settings.jellyseerr_url.rstrip("/") or "<unset>")
+    logger.info("Falling back to legacy Jellyseerr env settings")
     return JellyseerrClient(settings.jellyseerr_url, settings.jellyseerr_api_key)
 
 
-@lru_cache
-def get_ssh_client() -> RemoteSSHClient:
-    """Return a cached SSH client (connects on first use)."""
+def get_ssh_client(request: Request = None) -> RemoteSSHClient:
+    """Return a cached SSH client for the selected machine or legacy env fallback."""
+    machine = get_settings_store().get_machine_config(_request_machine_id(request)) or _resolve_machine("ssh", request)
+    if machine and machine.get("host") and machine.get("username") and machine.get("key_directory") and machine.get("key_name"):
+        known_hosts_path = get_settings().ssh_known_hosts_file
+        ensure_known_host(str(machine.get("host")), int(machine.get("port") or 22), known_hosts_path)
+        cache_key = (
+            machine["id"],
+            machine["host"],
+            machine["username"],
+            int(machine.get("port") or 22),
+            f"{machine.get('key_directory')}/{machine.get('key_name')}",
+            machine.get("password") or None,
+            str(known_hosts_path),
+        )
+        return _ssh_client_for(cache_key)
+
     settings = get_settings()
     logger.info(
-        "Creating SSH client host=%s user=%s port=%s key_dir=%s key_name=%s password=%s",
+        "Creating SSH client from legacy env host=%s user=%s port=%s key_dir=%s key_name=%s password=%s",
         settings.ssh_host or "<unset>",
         settings.ssh_username or "<unset>",
         settings.ssh_port,
@@ -60,20 +163,9 @@ def get_ssh_client() -> RemoteSSHClient:
         "set" if settings.ssh_password else "missing",
     )
     if not settings.ssh_key_path:
-        raise RuntimeError("SSH_KEY_DIRECTORY and SSH_KEY_NAME must be configured")
-    client = RemoteSSHClient(
-        host=settings.ssh_host,
-        username=settings.ssh_username,
-        port=settings.ssh_port,
-        key_filename=settings.ssh_key_path,
-        password=settings.ssh_password or None,
-    )
-    try:
-        client.connect()
-    except Exception:
-        logger.exception("Failed to establish SSH connection to %s", settings.ssh_host or "<unset>")
-        raise
-    return client
+        raise RuntimeError("No SSH machine is configured and SSH key settings must be configured")
+    ensure_known_host(settings.ssh_host, settings.ssh_port, settings.ssh_known_hosts_file)
+    return _ssh_client_for(("legacy", settings.ssh_host, settings.ssh_username, settings.ssh_port, settings.ssh_key_path, settings.ssh_password or None, str(settings.ssh_known_hosts_file)))
 
 
 def get_mail_queue() -> MailQueue:
@@ -91,13 +183,16 @@ def get_settings_store() -> SettingsStore:
     return _get_settings_store()
 
 
-def get_user_id() -> str:
-    """Return the configured Jellyfin user ID, or discover the first available user."""
+def get_user_id(request: Request = None) -> str:
+    """Return the configured Jellyfin user ID or discover the first available one."""
+    machine = get_settings_store().get_machine_config(_request_machine_id(request)) or _resolve_machine("jellyfin", request)
+    if machine and machine.get("jellyfin_user_id"):
+        return str(machine["jellyfin_user_id"])
     settings = get_settings()
     if settings.jellyfin_user_id:
         return settings.jellyfin_user_id
-    client = get_jellyfin_client()
+    client = get_jellyfin_client(request)
     users = client.users()
     if not users:
-        raise RuntimeError("No Jellyfin users found and JELLYFIN_USER_ID not set")
+        raise RuntimeError("No Jellyfin users found and no machine/user id configured")
     return users[0]["Id"]