fix(plex): a server without a machine id refuses the collection write by name

The missing identifier became server:/// in the write URI. Client tests over a MockTransport
(errors, paging, cutoff, write URIs, image transcode) and admin-route tests (connection test,
enabled-section sampling, no server URL in a 422, the one-time watch import).

backend/tests/test_plex_admin_routes.py

@@ -0,0 +1,154 @@
+"""routes/plex/admin — the connection test and the owner's watch-sync link (E32 S2: 37% covered).
+
+The connection test is the admin's one early warning that the media mount or path map is wrong, and
+it must not quote the server's URL back in a toast. The watch link runs the one-time "Plex is master"
+import exactly once. Plex itself is a stub.
+"""
+
+from sqlalchemy import select
+
+import app.routes.plex.admin as admin_routes
+from app import sysconfig
+from app.models import PlexLink
+from app.plex.client import PlexError, PlexNotConfigured
+
+
+class _Plex:
+    def __init__(self, *, sections=None, leaf=None, fail=None):
+        self._sections = sections or []
+        self._leaf = leaf
+        self._fail = fail
+        self.section_items_calls: list[str] = []
+
+    def __enter__(self):
+        if self._fail:
+            raise self._fail
+        return self
+
+    def __exit__(self, *exc):
+        return False
+
+    def server_info(self):
+        return {"friendlyName": "Basement", "version": "1.40"}
+
+    def sections(self):
+        return self._sections
+
+    def section_items(self, key, *_args):
+        self.section_items_calls.append(key)
+        return ([self._leaf] if self._leaf else []), 1
+
+
+SECTIONS = [
+    {"key": 1, "title": "Movies", "type": "movie", "count": 10},
+    {"key": 2, "title": "Shows", "type": "show", "count": 3},
+    {"key": 3, "title": "Music", "type": "artist", "count": 99},
+]
+LEAF = {"Media": [{"Part": [{"file": "/data/movies/a.mkv"}]}]}
+
+
+def _use(monkeypatch, plex):
+    monkeypatch.setattr(admin_routes, "PlexClient", lambda db: plex)
+
+
+def test_the_connection_test_lists_movie_and_show_sections_and_probes_one_file(
+    db, as_user, make_user, monkeypatch, tmp_path
+):
+    (tmp_path / "a.mkv").write_bytes(b"x")
+    sysconfig.set_value(db, "plex_path_map", f"/data/movies={tmp_path}")
+    sysconfig.set_value(db, "plex_libraries", "4")
+    db.commit()
+    # Only section 4 is enabled; the movie section listed first (1) must not be the one sampled.
+    other = {"key": 4, "title": "Kids", "type": "movie", "count": 2}
+    plex = _Plex(sections=[*SECTIONS, other], leaf=LEAF)
+    _use(monkeypatch, plex)
+    r = as_user(make_user(role="admin")).post("/api/plex/test")
+    assert r.status_code == 200, r.text
+    body = r.json()
+    assert body["server_name"] == "Basement"
+    assert [s["key"] for s in body["sections"]] == ["1", "2", "4"]  # music is not ours
+    assert body["media_check"] == {
+        "checked": True,
+        "ok": True,
+        "plex_path": "/data/movies/a.mkv",
+        "local_path": str(tmp_path / "a.mkv"),
+    }
+    assert plex.section_items_calls == ["4"]  # only an enabled movie section is sampled
+
+
+def test_a_wrong_mount_is_reported_and_an_empty_library_is_not_checked(
+    db, as_user, make_user, monkeypatch, tmp_path
+):
+    sysconfig.set_value(db, "plex_path_map", f"/data/movies={tmp_path}")
+    db.commit()
+    client = as_user(make_user(role="admin"))
+    _use(monkeypatch, _Plex(sections=SECTIONS, leaf=LEAF))  # the file is not on the mount
+    check = client.post("/api/plex/test").json()["media_check"]
+    assert check["checked"] is True and check["ok"] is False
+
+    _use(monkeypatch, _Plex(sections=SECTIONS))
+    assert client.post("/api/plex/test").json()["media_check"] == {"checked": False}
+
+
+def test_a_failed_connection_says_so_without_quoting_the_server(
+    db, as_user, make_user, monkeypatch
+):
+    client = as_user(make_user(role="admin"))
+    _use(monkeypatch, _Plex(fail=PlexNotConfigured()))
+    r = client.post("/api/plex/test")
+    assert r.status_code == 400
+    assert r.json()["detail"]["reason"] == "plex_not_configured"
+
+    _use(monkeypatch, _Plex(fail=PlexError("GET http://10.0.0.5:32400/secret refused")))
+    r = client.post("/api/plex/test")
+    assert r.status_code == 422
+    assert r.json()["detail"]["reason"] == "plex_unreachable"
+    assert "10.0.0.5" not in r.text
+
+
+def test_plex_admin_routes_refuse_a_regular_user(db, as_user, make_user, monkeypatch):
+    _use(monkeypatch, _Plex(sections=SECTIONS))
+    client = as_user(make_user())
+    for path in ("/api/plex/test", "/api/plex/sync", "/api/plex/watch/import"):
+        assert client.post(path).status_code == 403, path
+    assert client.post("/api/plex/watch/link", json={"enabled": True}).status_code == 403
+
+
+def test_the_watch_link_imports_once_and_needs_plex_on(db, as_user, make_user, monkeypatch):
+    imports: list[int] = []
+
+    def fake_import(db_, link):
+        imports.append(link.user_id)
+        link.initial_import_done = True
+        db_.commit()
+        return {"imported": 7}
+
+    monkeypatch.setattr(admin_routes.plex_watch, "import_owner_watch_state", fake_import)
+    owner = make_user(role="admin")
+    client = as_user(owner)
+
+    r = client.post("/api/plex/watch/link", json={"enabled": True})
+    assert r.status_code == 409 and r.json()["detail"]["reason"] == "plex_disabled"
+    assert client.post("/api/plex/watch/import").json()["detail"]["reason"] == "watch_sync_off"
+
+    sysconfig.set_value(db, "plex_enabled", True)
+    db.commit()
+    first = client.post("/api/plex/watch/link", json={"enabled": True})
+    assert first.status_code == 200
+    assert first.json()["import"] == {"imported": 7}
+    assert first.json()["linked"] and first.json()["sync_enabled"] and first.json()["uses_admin"]
+
+    assert client.post("/api/plex/watch/link", json={"enabled": False}).json()["import"] is None
+    again = client.post("/api/plex/watch/link", json={"enabled": True})
+    assert again.json()["import"] is None  # the one-time import does not run twice
+    assert imports == [owner.id]
+
+    status = client.get("/api/plex/watch/link")
+    assert status.status_code == 200
+    assert status.json()["initial_import_done"] is True
+    links = db.execute(select(PlexLink).where(PlexLink.user_id == owner.id)).scalars().all()
+    assert len(links) == 1  # toggling never creates a second link
+
+    rerun = client.post("/api/plex/watch/import")
+    assert rerun.status_code == 200 and rerun.json()["import"] == {"imported": 7}
+    assert imports == [owner.id, owner.id]