"""Instance-scoping of the uninspectable-holder fallback. Field-verified 2026-09-07 on a production host running TWO independent Hermes instances: a main gateway (user ``ubuntu``, HERMES_HOME=/home/ubuntu/.hermes) and a demo gateway (user ``demo``, HERMES_HOME=/home/demo/.hermes). The demo gateway runs as another user, so its ``/proc//fd`` table is unreadable from the main instance and the holder scan falls back to ``/proc//cmdline`` + ``_looks_like_hermes``. The demo process's argv matches the Hermes patterns exactly, so the fallback flagged it as an uninspectable holder of the MAIN instance's state.db even though ``lsof`` proved zero open handles on it. Consequence: the stale-FTS rebuild in ``hermes_state_schema._recover_stale_fts`` was deferred 42 times across 6 gateway restarts, the ``fts_stale`` breadcrumb never cleared, and FTS self-repair stayed permanently disabled. PR #92419 fixed substring false positives (journalctl/grep mentioning hermes); a genuine second instance with a DIFFERENT HERMES_HOME is still misjudged on current main (issue #92401). Behavior contract: an uninspectable holder identified only by argv must be counted unless its own argv proves it is scoped to a *different* Hermes home / state.db and never references ours. Ambiguous argv (no absolute paths at all) must remain fail-closed, exactly as before — the conservative intent of the fallback is preserved. """ import os import pytest import hermes_state_holders # Capture the pristine stdlib functions at import time: monkeypatched calls # re-enter these closures, and re-capturing ``os.listdir`` after a previous # patch would compose the fakes into a double path-rewrite. _REAL_LISTDIR = os.listdir _REAL_READLINK = os.readlink # Representative demo-gateway argv on the two-instance host: every absolute # token lives under /home/demo/.hermes, the binary name matches the Hermes # patterns, and nothing references the main instance's home or state.db. DEMO_HOME_ARGV = [ "/home/demo/.hermes/hermes-agent/hermes", "gateway", "run", ] # Same, spelled through the venv interpreter + hermes launcher script. DEMO_VENV_ARGV = [ "/home/demo/.hermes/hermes-agent/venv/bin/python", "/home/demo/.hermes/hermes-agent/hermes_cli/main.py", "gateway", ] # A Hermes-shaped argv with no absolute paths: cannot disprove that this # process touches our state.db, so it must stay fail-closed. AMBIGUOUS_ARGV = ["hermes", "gateway", "run"] def _install_fake_proc(monkeypatch, tmp_path, unreadable_pids=(), fd_pids=()): """Redirect the module's /proc access to an inert fake tree. PIDs in ``unreadable_pids`` raise PermissionError on their fd dir (cross-user process); PIDs in ``fd_pids`` expose an empty-but-listable fd dir whose single descriptor fails readlink with EACCES (uninspectable-descriptor branch). """ proc_root = tmp_path / "proc" for pid in set(unreadable_pids) | set(fd_pids): (proc_root / str(pid)).mkdir(parents=True, exist_ok=True) for pid in fd_pids: (proc_root / str(pid) / "fd").mkdir(exist_ok=True) (proc_root / str(pid) / "fd" / "3").touch(exist_ok=True) monkeypatch.setattr(hermes_state_holders.os, "getpid", lambda: 111) def _listdir(path): if isinstance(path, str): for pid in unreadable_pids: if path == f"/proc/{pid}/fd": raise PermissionError(errno_value("EACCES"), path) path = path.replace("/proc", str(proc_root)) return _REAL_LISTDIR(path) monkeypatch.setattr(hermes_state_holders.os, "listdir", _listdir) def _readlink(path): if "222/fd/3" in str(path): raise PermissionError(errno_value("EACCES"), str(path)) return _REAL_READLINK(str(path).replace("/proc", str(proc_root))) monkeypatch.setattr(hermes_state_holders.os, "readlink", _readlink) def errno_value(name): import errno return getattr(errno, name) def _install_fake_argv(monkeypatch, argv_by_pid): monkeypatch.setattr( hermes_state_holders, "_read_proc_argv", lambda pid: list(argv_by_pid.get(pid)) if pid in argv_by_pid else None, ) @pytest.mark.linux_only class TestUninspectableHolderInstanceScope: def test_other_instance_argv_is_not_a_holder_of_our_db(self, tmp_path, monkeypatch): """RED: fd dir unreadable + argv proves the process belongs to a DIFFERENT Hermes home → not a holder of our state.db.""" # A real ``.hermes`` home, as on the field host this test is drawn from: the install # location can only identify a home that is itself part of an install layout. db_path = tmp_path / ".hermes" / "state.db" _install_fake_proc(monkeypatch, tmp_path, unreadable_pids=(222,)) _install_fake_argv(monkeypatch, {222: DEMO_HOME_ARGV}) holders = hermes_state_holders.foreign_state_db_holders(db_path) assert holders == [] def test_argv_referencing_our_db_stays_flagged(self, tmp_path, monkeypatch): """A (possibly second) instance whose argv names OUR state.db, our sidecars, or our home must still be fail-closed flagged.""" db_path = tmp_path / "state.db" our_home = str(tmp_path) for argv in ( ["hermes", f"--db={db_path}", "gateway"], ["hermes", "checkpoint", f"{db_path}-wal"], ["hermes", "--home", our_home, "gateway"], ): assert hermes_state_holders._looks_like_hermes(argv) or argv[0] == "hermes" _install_fake_proc(monkeypatch, tmp_path, unreadable_pids=(222,)) _install_fake_argv(monkeypatch, {222: argv}) holders = hermes_state_holders.foreign_state_db_holders(db_path) assert [pid for pid, _ in holders] == [222], argv assert holders[0][1].startswith("uninspectable holder:"), argv def test_install_root_argv_still_holds_a_profile_store_under_it(self, tmp_path, monkeypatch): """One process per host serves EVERY profile, so argv naming only the install root does not prove the process is another instance: it holds ``/profiles//state.db`` too. A DIFFERENT install root is still proof.""" root = tmp_path / ".hermes" db_path = root / "profiles" / "b" / "state.db" db_path.parent.mkdir(parents=True) multiplexer = ["hermes", "--home", str(root), "gateway", "run"] other_install = ["hermes", "--home", "/home/demo/.hermes", "gateway", "run"] _install_fake_proc(monkeypatch, db_path.parent, unreadable_pids=(222,)) _install_fake_argv(monkeypatch, {222: multiplexer}) assert [pid for pid, _ in hermes_state_holders.foreign_state_db_holders(db_path)] == [222] _install_fake_proc(monkeypatch, db_path.parent, unreadable_pids=(222,)) _install_fake_argv(monkeypatch, {222: other_install}) assert hermes_state_holders.foreign_state_db_holders(db_path) == [] def test_shared_binary_plus_another_profile_selection_is_dismissed(self, tmp_path, monkeypatch): """argv[0] is the SHARED install binary, so it cannot prove a hold of profile b's store. Every hermes process on a normal host runs ``/venv/bin/hermes``; counting that token as proof made ``hermes -p other chat -q`` an uninspectable holder of every OTHER profile's state.db, deferring its FTS rebuild and auto-VACUUM for as long as the sibling lived (#92401, inside a single install). The process's own ``-p``/``--profile`` selection decides. """ root = tmp_path / ".hermes" db_path = root / "profiles" / "b" / "state.db" db_path.parent.mkdir(parents=True) shared_binary = str(root / "venv" / "bin" / "hermes") for argv, expected in ( ([shared_binary, "-p", "other", "chat", "-q"], []), ([shared_binary, "--profile=other", "gateway", "run"], []), # Control: the sibling that DOES serve profile b is still a fail-closed holder. ([shared_binary, "-p", "b", "gateway", "run"], [222]), # Control: no selection at all stays fail-closed (it may be the multiplexer). ([shared_binary, "gateway", "run"], [222]), ): _install_fake_proc(monkeypatch, db_path.parent, unreadable_pids=(222,)) _install_fake_argv(monkeypatch, {222: argv}) holders = hermes_state_holders.foreign_state_db_holders(db_path) assert [pid for pid, _ in holders] == expected, argv def test_token_naming_another_profiles_store_is_dismissal_evidence(self, tmp_path, monkeypatch): """A token positively naming ANOTHER profile's store is the strongest dismissal there is. It sits under our install root, so a blanket own-prefix test read the strongest evidence of a different scope as proof of ours. """ root = tmp_path / ".hermes" db_path = root / "profiles" / "b" / "state.db" db_path.parent.mkdir(parents=True) other_store = root / "profiles" / "other" / "state.db" for argv in ( ["hermes", f"--db={other_store}", "sessions", "optimize"], [str(root / "venv" / "bin" / "hermes"), "sessions", str(other_store)], ): _install_fake_proc(monkeypatch, db_path.parent, unreadable_pids=(222,)) _install_fake_argv(monkeypatch, {222: argv}) assert hermes_state_holders.foreign_state_db_holders(db_path) == [], argv def test_unrelated_install_under_a_non_hermes_profiles_tree_stays_dismissed( self, tmp_path, monkeypatch ): """``/profiles//state.db`` does not make all of ```` ours. A raw ``basename == "profiles"`` test promoted any such parent to the install root, so an unrelated Hermes install living under it was counted as a holder — the literal two-instance shape #92401 was filed about. The canonical ``named_profile_home`` predicate requires the parent to be a real Hermes home. """ work = tmp_path / "work" db_path = work / "profiles" / "b" / "state.db" db_path.parent.mkdir(parents=True) unrelated_home = work / "demo" / ".hermes" unrelated_home.mkdir(parents=True) _install_fake_proc(monkeypatch, db_path.parent, unreadable_pids=(222,)) _install_fake_argv( monkeypatch, {222: ["hermes", "--hermes-home", str(unrelated_home), "gateway", "run"]}) assert hermes_state_holders.foreign_state_db_holders(db_path) == [] def test_custom_home_is_not_dismissed_by_the_install_location(self, tmp_path, monkeypatch): """A store at a custom HERMES_HOME is SERVED BY the binary under ``~/.hermes``. Dismissing on that argv[0] admitted auto-VACUUM and the FTS rebuild under the live multiplexer that holds the store. argv[0] locates the install, never the home. """ db_path = tmp_path / "custom-store" / "state.db" db_path.parent.mkdir(parents=True) _install_fake_proc(monkeypatch, db_path.parent, unreadable_pids=(222,)) _install_fake_argv( monkeypatch, {222: ["/home/u/.hermes/venv/bin/hermes", "gateway", "run"]}) holders = hermes_state_holders.foreign_state_db_holders(db_path) assert [pid for pid, _ in holders] == [222]