deer-flow/backend/tests/test_app_config_reload.py

from __future__ import annotations

import json
import os
from pathlib import Path

import pytest
import yaml
from pydantic import ValidationError

import deerflow.config.app_config as app_config_module
from deerflow.config.acp_config import load_acp_config_from_dict
from deerflow.config.agents_api_config import get_agents_api_config, load_agents_api_config_from_dict
from deerflow.config.app_config import AppConfig, get_app_config, reset_app_config
from deerflow.config.checkpointer_config import get_checkpointer_config, load_checkpointer_config_from_dict
from deerflow.config.database_config import DatabaseConfig
from deerflow.config.guardrails_config import get_guardrails_config, load_guardrails_config_from_dict
from deerflow.config.memory_config import get_memory_config, load_memory_config_from_dict
from deerflow.config.stream_bridge_config import get_stream_bridge_config, load_stream_bridge_config_from_dict
from deerflow.config.subagents_config import get_subagents_app_config, load_subagents_config_from_dict
from deerflow.config.summarization_config import get_summarization_config, load_summarization_config_from_dict
from deerflow.config.title_config import get_title_config, load_title_config_from_dict
from deerflow.config.tool_search_config import get_tool_search_config, load_tool_search_config_from_dict
from deerflow.runtime.checkpointer import get_checkpointer, reset_checkpointer
from deerflow.runtime.store import get_store, reset_store


def _reset_config_singletons() -> None:
    load_title_config_from_dict({})
    load_summarization_config_from_dict({})
    load_memory_config_from_dict({})
    load_agents_api_config_from_dict({})
    load_subagents_config_from_dict({})
    load_tool_search_config_from_dict({})
    load_guardrails_config_from_dict({})
    load_checkpointer_config_from_dict(None)
    load_stream_bridge_config_from_dict(None)
    load_acp_config_from_dict({})
    reset_checkpointer()
    reset_store()
    reset_app_config()


def _write_config(path: Path, *, model_name: str, supports_thinking: bool) -> None:
    path.write_text(
        yaml.safe_dump(
            {
                "sandbox": {"use": "deerflow.sandbox.local:LocalSandboxProvider"},
                "models": [
                    {
                        "name": model_name,
                        "use": "langchain_openai:ChatOpenAI",
                        "model": "gpt-test",
                        "supports_thinking": supports_thinking,
                    }
                ],
            }
        ),
        encoding="utf-8",
    )


def _write_config_with_agents_api(
    path: Path,
    *,
    model_name: str,
    supports_thinking: bool,
    agents_api: dict | None = None,
) -> None:
    config = {
        "sandbox": {"use": "deerflow.sandbox.local:LocalSandboxProvider"},
        "models": [
            {
                "name": model_name,
                "use": "langchain_openai:ChatOpenAI",
                "model": "gpt-test",
                "supports_thinking": supports_thinking,
            }
        ],
    }
    if agents_api is not None:
        config["agents_api"] = agents_api

    path.write_text(yaml.safe_dump(config), encoding="utf-8")


def _write_config_with_sections(path: Path, sections: dict | None = None) -> None:
    config = {
        "sandbox": {"use": "deerflow.sandbox.local:LocalSandboxProvider"},
        "models": [
            {
                "name": "first-model",
                "use": "langchain_openai:ChatOpenAI",
                "model": "gpt-test",
            }
        ],
    }
    if sections:
        config.update(sections)

    path.write_text(yaml.safe_dump(config), encoding="utf-8")


def _write_extensions_config(path: Path) -> None:
    path.write_text(json.dumps({"mcpServers": {}, "skills": {}}), encoding="utf-8")


def test_checkpoint_channel_mode_defaults_to_full() -> None:
    assert DatabaseConfig().checkpoint_channel_mode == "full"


@pytest.mark.parametrize("mode", ["full", "delta"])
def test_checkpoint_channel_mode_accepts_supported_values(mode: str) -> None:
    assert DatabaseConfig(checkpoint_channel_mode=mode).checkpoint_channel_mode == mode


def test_checkpoint_channel_mode_rejects_unknown_value() -> None:
    with pytest.raises(ValidationError):
        DatabaseConfig(checkpoint_channel_mode="auto")


def test_checkpoint_delta_defaults_to_production_cadence() -> None:
    assert DatabaseConfig().checkpoint_delta.snapshot_frequency == 10


def test_checkpoint_delta_accepts_custom_snapshot_frequency() -> None:
    assert DatabaseConfig(checkpoint_delta={"snapshot_frequency": 250}).checkpoint_delta.snapshot_frequency == 250


@pytest.mark.parametrize("value", [0, -1])
def test_checkpoint_delta_rejects_non_positive_snapshot_frequency(value: int) -> None:
    with pytest.raises(ValidationError):
        DatabaseConfig(checkpoint_delta={"snapshot_frequency": value})


def test_legacy_snapshot_frequency_maps_to_nested_key(caplog: pytest.LogCaptureFixture) -> None:
    with caplog.at_level("WARNING"):
        config = DatabaseConfig(checkpoint_delta_snapshot_frequency=1000)
    assert config.checkpoint_delta.snapshot_frequency == 1000
    assert "checkpoint_delta_snapshot_frequency is deprecated" in caplog.text


def test_nested_snapshot_frequency_wins_over_legacy_key(caplog: pytest.LogCaptureFixture) -> None:
    with caplog.at_level("WARNING"):
        config = DatabaseConfig(
            checkpoint_delta_snapshot_frequency=1000,
            checkpoint_delta={"snapshot_frequency": 250},
        )
    assert config.checkpoint_delta.snapshot_frequency == 250
    assert "the nested key wins" in caplog.text


@pytest.mark.parametrize("value", [0, -1])
def test_legacy_snapshot_frequency_rejects_non_positive_value(value: int) -> None:
    with pytest.raises(ValidationError):
        DatabaseConfig(checkpoint_delta_snapshot_frequency=value)


def test_checkpoint_graph_cache_defaults() -> None:
    assert DatabaseConfig().checkpoint_graph_cache.accessor_graph_max == 64


def test_checkpoint_graph_cache_accepts_custom_cap() -> None:
    assert DatabaseConfig(checkpoint_graph_cache={"accessor_graph_max": 8}).checkpoint_graph_cache.accessor_graph_max == 8


@pytest.mark.parametrize("value", [0, -1])
def test_checkpoint_graph_cache_rejects_non_positive_cap(value: int) -> None:
    with pytest.raises(ValidationError):
        DatabaseConfig(checkpoint_graph_cache={"accessor_graph_max": value})


def test_resolve_checkpoint_graph_cache_max_tolerates_stub_configs() -> None:
    from types import SimpleNamespace
    from unittest.mock import MagicMock

    from deerflow.config.database_config import resolve_checkpoint_graph_cache_max

    assert resolve_checkpoint_graph_cache_max(None, "accessor_graph_max", 64) == 64
    assert resolve_checkpoint_graph_cache_max(SimpleNamespace(), "accessor_graph_max", 64) == 64
    assert resolve_checkpoint_graph_cache_max(MagicMock(), "accessor_graph_max", 64) == 64
    stub = SimpleNamespace(checkpoint_graph_cache=SimpleNamespace(accessor_graph_max=3))
    assert resolve_checkpoint_graph_cache_max(stub, "accessor_graph_max", 64) == 3


def test_config_example_does_not_enable_empty_extensions_block_by_default():
    config_example_path = Path(__file__).resolve().parents[2] / "config.example.yaml"

    config_data = yaml.safe_load(config_example_path.read_text(encoding="utf-8"))

    assert "extensions" not in config_data


def test_app_config_defaults_missing_database_to_sqlite(tmp_path, monkeypatch):
    config_path = tmp_path / "config.yaml"
    extensions_path = tmp_path / "extensions_config.json"
    _write_extensions_config(extensions_path)
    _write_config(config_path, model_name="first-model", supports_thinking=False)

    monkeypatch.setenv("DEER_FLOW_EXTENSIONS_CONFIG_PATH", str(extensions_path))

    config = AppConfig.from_file(str(config_path))

    assert config.database.backend == "sqlite"
    assert config.database.sqlite_dir == ".deer-flow/data"


def test_app_config_preserves_config_yaml_extension_middlewares(tmp_path, monkeypatch):
    config_path = tmp_path / "config.yaml"
    extensions_path = tmp_path / "extensions_config.json"
    extensions_path.write_text(
        json.dumps({"mcpServers": {}, "skills": {}, "middlewares": ["pkg.from_file:FileMiddleware"]}),
        encoding="utf-8",
    )
    _write_config_with_sections(
        config_path,
        {
            "extensions": {
                "middlewares": ["pkg.from_yaml:YamlMiddleware"],
            }
        },
    )
    monkeypatch.setenv("DEER_FLOW_EXTENSIONS_CONFIG_PATH", str(extensions_path))

    config = AppConfig.from_file(str(config_path))

    assert config.extensions.middlewares == ["pkg.from_yaml:YamlMiddleware"]


def test_app_config_normalizes_config_yaml_extension_aliases_before_override(tmp_path, monkeypatch):
    config_path = tmp_path / "config.yaml"
    extensions_path = tmp_path / "extensions_config.json"
    extensions_path.write_text(
        json.dumps(
            {
                "mcpServers": {
                    "from-file": {
                        "command": "file-mcp",
                    }
                },
                "skills": {},
            }
        ),
        encoding="utf-8",
    )
    _write_config_with_sections(
        config_path,
        {
            "extensions": {
                "mcp_servers": {
                    "from-yaml": {
                        "command": "yaml-mcp",
                    }
                },
            }
        },
    )
    monkeypatch.setenv("DEER_FLOW_EXTENSIONS_CONFIG_PATH", str(extensions_path))

    config = AppConfig.from_file(str(config_path))

    assert set(config.extensions.mcp_servers) == {"from-yaml"}
    assert config.extensions.mcp_servers["from-yaml"].command == "yaml-mcp"


def test_app_config_loads_extension_middlewares_from_extensions_config(tmp_path, monkeypatch):
    config_path = tmp_path / "config.yaml"
    extensions_path = tmp_path / "extensions_config.json"
    extensions_path.write_text(
        json.dumps({"mcpServers": {}, "skills": {}, "middlewares": ["pkg.from_file:FileMiddleware"]}),
        encoding="utf-8",
    )
    _write_config_with_sections(config_path)
    monkeypatch.setenv("DEER_FLOW_EXTENSIONS_CONFIG_PATH", str(extensions_path))

    config = AppConfig.from_file(str(config_path))

    assert config.extensions.middlewares == ["pkg.from_file:FileMiddleware"]


def test_app_config_defaults_empty_database_to_sqlite(tmp_path, monkeypatch):
    config_path = tmp_path / "config.yaml"
    extensions_path = tmp_path / "extensions_config.json"
    _write_extensions_config(extensions_path)
    config_path.write_text(
        yaml.safe_dump(
            {
                "database": {},
                "sandbox": {"use": "deerflow.sandbox.local:LocalSandboxProvider"},
            }
        ),
        encoding="utf-8",
    )

    monkeypatch.setenv("DEER_FLOW_EXTENSIONS_CONFIG_PATH", str(extensions_path))

    config = AppConfig.from_file(str(config_path))

    assert config.database.backend == "sqlite"
    assert config.database.sqlite_dir == ".deer-flow/data"


def test_app_config_coerces_commented_out_list_sections(tmp_path, monkeypatch):
    """Commenting out every entry under a list key makes PyYAML parse it as None.

    Regression for the documented ``cp config.example.yaml config.yaml`` flow
    (issue #1444): such a config must load with empty lists instead of raising
    ``Input should be a valid list``.
    """
    config_path = tmp_path / "config.yaml"
    extensions_path = tmp_path / "extensions_config.json"
    _write_extensions_config(extensions_path)
    config_path.write_text(
        yaml.safe_dump(
            {
                "sandbox": {"use": "deerflow.sandbox.local:LocalSandboxProvider"},
                "models": None,
                "tools": None,
                "tool_groups": None,
            }
        ),
        encoding="utf-8",
    )
    monkeypatch.setenv("DEER_FLOW_EXTENSIONS_CONFIG_PATH", str(extensions_path))

    config = AppConfig.from_file(str(config_path))

    assert config.models == []
    assert config.tools == []
    assert config.tool_groups == []


def test_app_config_coerces_commented_out_object_sections(tmp_path, monkeypatch):
    """Commenting out every entry under an object key makes PyYAML parse it as None.

    Same documented ``cp config.example.yaml config.yaml`` flow as the list
    sections: object sections (memory, summarization, ...) must fall back to
    their defaults instead of raising ``Input should be a valid dictionary``.
    """
    config_path = tmp_path / "config.yaml"
    extensions_path = tmp_path / "extensions_config.json"
    _write_extensions_config(extensions_path)
    config_path.write_text(
        yaml.safe_dump(
            {
                "sandbox": {"use": "deerflow.sandbox.local:LocalSandboxProvider"},
                "memory": None,
                "summarization": None,
                "guardrails": None,
                "tool_output": None,
                "run_events": None,
            }
        ),
        encoding="utf-8",
    )
    monkeypatch.setenv("DEER_FLOW_EXTENSIONS_CONFIG_PATH", str(extensions_path))

    config = AppConfig.from_file(str(config_path))

    # Each present-but-null object section falls back to a real default config
    # object of the expected type (not merely non-None).
    assert type(config.memory).__name__ == "MemoryConfig"
    assert type(config.summarization).__name__ == "SummarizationConfig"
    assert type(config.guardrails).__name__ == "GuardrailsConfig"
    assert type(config.tool_output).__name__ == "ToolOutputConfig"
    assert type(config.run_events).__name__ == "RunEventsConfig"


def test_app_config_null_required_section_still_errors(tmp_path, monkeypatch):
    """A present-but-null *required* section still errors.

    ``sandbox`` has no default, so dropping a ``sandbox: null`` key leaves the
    required field absent — there is nothing to fall back to (per
    ``_drop_null_config_sections``), unlike the optional object sections above.
    """
    config_path = tmp_path / "config.yaml"
    extensions_path = tmp_path / "extensions_config.json"
    _write_extensions_config(extensions_path)
    config_path.write_text(yaml.safe_dump({"sandbox": None}), encoding="utf-8")
    monkeypatch.setenv("DEER_FLOW_EXTENSIONS_CONFIG_PATH", str(extensions_path))

    with pytest.raises(ValidationError):
        AppConfig.from_file(str(config_path))


def test_app_config_warns_when_no_models_configured(tmp_path, monkeypatch, caplog):
    config_path = tmp_path / "config.yaml"
    extensions_path = tmp_path / "extensions_config.json"
    _write_extensions_config(extensions_path)
    config_path.write_text(
        yaml.safe_dump(
            {
                "sandbox": {"use": "deerflow.sandbox.local:LocalSandboxProvider"},
                "models": None,
            }
        ),
        encoding="utf-8",
    )
    monkeypatch.setenv("DEER_FLOW_EXTENSIONS_CONFIG_PATH", str(extensions_path))

    with caplog.at_level("WARNING", logger="deerflow.config.app_config"):
        AppConfig.from_file(str(config_path))

    assert "No models are configured" in caplog.text


def test_get_app_config_reloads_when_file_changes(tmp_path, monkeypatch):
    config_path = tmp_path / "config.yaml"
    extensions_path = tmp_path / "extensions_config.json"
    _write_extensions_config(extensions_path)
    _write_config(config_path, model_name="first-model", supports_thinking=False)

    monkeypatch.setenv("DEER_FLOW_CONFIG_PATH", str(config_path))
    monkeypatch.setenv("DEER_FLOW_EXTENSIONS_CONFIG_PATH", str(extensions_path))
    reset_app_config()

    try:
        initial = get_app_config()
        assert initial.models[0].supports_thinking is False

        _write_config(config_path, model_name="first-model", supports_thinking=True)
        next_mtime = config_path.stat().st_mtime + 5
        os.utime(config_path, (next_mtime, next_mtime))

        reloaded = get_app_config()
        assert reloaded.models[0].supports_thinking is True
        assert reloaded is not initial
    finally:
        reset_app_config()


def test_get_app_config_reloads_when_content_digest_changes_without_metadata(tmp_path, monkeypatch):
    config_path = tmp_path / "config.yaml"
    extensions_path = tmp_path / "extensions_config.json"
    _write_extensions_config(extensions_path)
    _write_config(config_path, model_name="model-a", supports_thinking=False)

    monkeypatch.setenv("DEER_FLOW_CONFIG_PATH", str(config_path))
    monkeypatch.setenv("DEER_FLOW_EXTENSIONS_CONFIG_PATH", str(extensions_path))
    _reset_config_singletons()

    try:
        initial = get_app_config()
        initial_mtime = app_config_module._app_config_mtime
        initial_signature = app_config_module._app_config_signature
        assert initial.models[0].name == "model-a"
        assert initial_signature is not None

        _write_config(config_path, model_name="model-b", supports_thinking=False)

        real_get_config_signature = app_config_module._get_config_signature

        def stale_metadata_signature(path: Path):
            current_signature = real_get_config_signature(path)
            assert current_signature is not None
            return (initial_signature[0], initial_signature[1], current_signature[2])

        monkeypatch.setattr(app_config_module, "_get_config_mtime", lambda _path: initial_mtime)
        monkeypatch.setattr(app_config_module, "_get_config_signature", stale_metadata_signature)

        reloaded = get_app_config()
        assert reloaded.models[0].name == "model-b"
        assert reloaded is not initial
        assert app_config_module._app_config_signature is not None
        assert app_config_module._app_config_signature[:2] == initial_signature[:2]
        assert app_config_module._app_config_signature[2] != initial_signature[2]
    finally:
        _reset_config_singletons()


def test_get_app_config_reloads_when_config_path_changes(tmp_path, monkeypatch):
    config_a = tmp_path / "config-a.yaml"
    config_b = tmp_path / "config-b.yaml"
    extensions_path = tmp_path / "extensions_config.json"
    _write_extensions_config(extensions_path)
    _write_config(config_a, model_name="model-a", supports_thinking=False)
    _write_config(config_b, model_name="model-b", supports_thinking=True)

    monkeypatch.setenv("DEER_FLOW_EXTENSIONS_CONFIG_PATH", str(extensions_path))
    monkeypatch.setenv("DEER_FLOW_CONFIG_PATH", str(config_a))
    reset_app_config()

    try:
        first = get_app_config()
        assert first.models[0].name == "model-a"

        monkeypatch.setenv("DEER_FLOW_CONFIG_PATH", str(config_b))
        second = get_app_config()
        assert second.models[0].name == "model-b"
        assert second is not first
    finally:
        reset_app_config()


def test_get_app_config_resets_agents_api_config_when_section_removed(tmp_path, monkeypatch):
    config_path = tmp_path / "config.yaml"
    extensions_path = tmp_path / "extensions_config.json"
    _write_extensions_config(extensions_path)
    _write_config_with_agents_api(
        config_path,
        model_name="first-model",
        supports_thinking=False,
        agents_api={"enabled": True},
    )

    monkeypatch.setenv("DEER_FLOW_CONFIG_PATH", str(config_path))
    monkeypatch.setenv("DEER_FLOW_EXTENSIONS_CONFIG_PATH", str(extensions_path))
    reset_app_config()

    try:
        initial = get_app_config()
        assert initial.models[0].name == "first-model"
        assert get_agents_api_config().enabled is True

        _write_config_with_agents_api(
            config_path,
            model_name="first-model",
            supports_thinking=False,
        )
        next_mtime = config_path.stat().st_mtime + 5
        os.utime(config_path, (next_mtime, next_mtime))

        reloaded = get_app_config()
        assert reloaded is not initial
        assert get_agents_api_config().enabled is False
    finally:
        reset_app_config()


def test_get_app_config_resets_singleton_configs_when_sections_removed(tmp_path, monkeypatch):
    config_path = tmp_path / "config.yaml"
    extensions_path = tmp_path / "extensions_config.json"
    _write_extensions_config(extensions_path)
    _write_config_with_sections(
        config_path,
        {
            "title": {"enabled": False, "max_words": 3},
            "summarization": {"enabled": True},
            "memory": {"enabled": False, "max_facts": 50},
            "subagents": {"timeout_seconds": 42, "agents": {"reviewer": {"max_turns": 2}}},
            "tool_search": {"enabled": True},
            "guardrails": {"enabled": True, "fail_closed": False},
            "checkpointer": {"type": "memory"},
            "stream_bridge": {"type": "memory", "queue_maxsize": 12},
        },
    )

    monkeypatch.setenv("DEER_FLOW_CONFIG_PATH", str(config_path))
    monkeypatch.setenv("DEER_FLOW_EXTENSIONS_CONFIG_PATH", str(extensions_path))
    reset_app_config()

    try:
        get_app_config()
        assert get_title_config().enabled is False
        assert get_summarization_config().enabled is True
        assert get_memory_config().enabled is False
        assert get_subagents_app_config().timeout_seconds == 42
        assert get_tool_search_config().enabled is True
        assert get_guardrails_config().enabled is True
        assert get_checkpointer_config() is not None
        assert get_stream_bridge_config() is not None

        _write_config_with_sections(config_path)
        next_mtime = config_path.stat().st_mtime + 5
        os.utime(config_path, (next_mtime, next_mtime))

        get_app_config()
        assert get_title_config().enabled is True
        assert get_summarization_config().enabled is False
        assert get_memory_config().enabled is True
        assert get_subagents_app_config().timeout_seconds == 1800
        assert get_tool_search_config().enabled is False
        assert get_guardrails_config().enabled is False
        assert get_checkpointer_config() is None
        assert get_stream_bridge_config() is None
    finally:
        _reset_config_singletons()


def test_get_app_config_resets_persistence_runtime_singletons_when_checkpointer_removed(tmp_path, monkeypatch):
    config_path = tmp_path / "config.yaml"
    extensions_path = tmp_path / "extensions_config.json"
    _write_extensions_config(extensions_path)
    _write_config_with_sections(config_path, {"checkpointer": {"type": "memory"}})

    monkeypatch.setenv("DEER_FLOW_CONFIG_PATH", str(config_path))
    monkeypatch.setenv("DEER_FLOW_EXTENSIONS_CONFIG_PATH", str(extensions_path))
    reset_checkpointer()
    reset_store()
    reset_app_config()

    try:
        get_app_config()
        initial_checkpointer = get_checkpointer()
        initial_store = get_store()

        _write_config_with_sections(config_path)
        next_mtime = config_path.stat().st_mtime + 5
        os.utime(config_path, (next_mtime, next_mtime))

        get_app_config()

        assert get_checkpointer_config() is None
        assert get_checkpointer() is not initial_checkpointer
        assert get_store() is not initial_store
    finally:
        _reset_config_singletons()


def test_get_app_config_keeps_persistence_runtime_singletons_when_checkpointer_unchanged(tmp_path, monkeypatch):
    config_path = tmp_path / "config.yaml"
    extensions_path = tmp_path / "extensions_config.json"
    _write_extensions_config(extensions_path)
    _write_config_with_sections(
        config_path,
        {
            "title": {"enabled": False},
            "checkpointer": {"type": "memory"},
        },
    )

    monkeypatch.setenv("DEER_FLOW_CONFIG_PATH", str(config_path))
    monkeypatch.setenv("DEER_FLOW_EXTENSIONS_CONFIG_PATH", str(extensions_path))
    _reset_config_singletons()

    try:
        get_app_config()
        initial_checkpointer = get_checkpointer()
        initial_store = get_store()

        _write_config_with_sections(
            config_path,
            {
                "title": {"enabled": True},
                "checkpointer": {"type": "memory"},
            },
        )
        next_mtime = config_path.stat().st_mtime + 5
        os.utime(config_path, (next_mtime, next_mtime))

        get_app_config()

        assert get_checkpointer() is initial_checkpointer
        assert get_store() is initial_store
    finally:
        _reset_config_singletons()


def test_get_app_config_does_not_reset_persistence_singletons_when_database_changes(tmp_path, monkeypatch):
    # ``database`` is a restart-required field: the ORM engine is built once at
    # startup and never rebuilt on a config.yaml edit. Resetting only the sync
    # checkpointer/store singletons on a live ``postgres_schema`` change would
    # half-migrate the deployment (new checkpoint/store tables in the new schema,
    # ORM rows still in the old one). So a ``database`` change must NOT trigger a
    # partial reset -- the operator must restart.
    config_path = tmp_path / "config.yaml"
    extensions_path = tmp_path / "extensions_config.json"
    _write_extensions_config(extensions_path)
    _write_config_with_sections(
        config_path,
        {"database": {"backend": "postgres", "postgres_url": "postgresql://localhost/db", "postgres_schema": "schema_a"}},
    )

    monkeypatch.setenv("DEER_FLOW_CONFIG_PATH", str(config_path))
    monkeypatch.setenv("DEER_FLOW_EXTENSIONS_CONFIG_PATH", str(extensions_path))
    _reset_config_singletons()

    reset_calls = {"checkpointer": 0, "store": 0}

    def _reset_checkpointer() -> None:
        reset_calls["checkpointer"] += 1

    def _reset_store() -> None:
        reset_calls["store"] += 1

    monkeypatch.setattr("deerflow.runtime.checkpointer.reset_checkpointer", _reset_checkpointer)
    monkeypatch.setattr("deerflow.runtime.store.reset_store", _reset_store)

    try:
        get_app_config()
        reset_calls["checkpointer"] = 0
        reset_calls["store"] = 0

        _write_config_with_sections(
            config_path,
            {"database": {"backend": "postgres", "postgres_url": "postgresql://localhost/db", "postgres_schema": "schema_b"}},
        )
        next_mtime = config_path.stat().st_mtime + 5
        os.utime(config_path, (next_mtime, next_mtime))

        get_app_config()

        assert get_checkpointer_config() is None
        assert reset_calls == {"checkpointer": 0, "store": 0}
    finally:
        _reset_config_singletons()


def test_get_app_config_does_not_mutate_singletons_when_reload_validation_fails(tmp_path, monkeypatch):
    config_path = tmp_path / "config.yaml"
    extensions_path = tmp_path / "extensions_config.json"
    _write_extensions_config(extensions_path)
    _write_config_with_sections(
        config_path,
        {
            "title": {"enabled": False},
            "tool_search": {"enabled": True},
            "checkpointer": {"type": "memory"},
        },
    )

    monkeypatch.setenv("DEER_FLOW_CONFIG_PATH", str(config_path))
    monkeypatch.setenv("DEER_FLOW_EXTENSIONS_CONFIG_PATH", str(extensions_path))
    _reset_config_singletons()

    try:
        previous_app_config = get_app_config()
        initial_checkpointer = get_checkpointer()
        initial_store = get_store()

        _write_config_with_sections(
            config_path,
            {
                "title": False,
                "tool_search": False,
                "checkpointer": {"type": "memory"},
            },
        )
        next_mtime = config_path.stat().st_mtime + 5
        os.utime(config_path, (next_mtime, next_mtime))

        with pytest.raises(ValidationError):
            get_app_config()

        assert app_config_module._app_config is previous_app_config
        assert get_title_config().enabled is False
        assert get_tool_search_config().enabled is True
        assert get_checkpointer_config() is not None
        assert get_checkpointer() is initial_checkpointer
        assert get_store() is initial_store
    finally:
        _reset_config_singletons()


def test_get_memory_config_self_syncs_without_prior_get_app_config(tmp_path, monkeypatch):
    """get_memory_config() triggers reload when file changes without prior get_app_config().

    Background memory paths (updater/queue/storage) never call get_app_config()
    directly.  This test pins the fix: calling get_memory_config() in isolation
    — after mutating the file, with no intervening get_app_config() — reflects
    the new value.
    """
    config_path = tmp_path / "config.yaml"
    extensions_path = tmp_path / "extensions_config.json"
    _write_extensions_config(extensions_path)

    _write_config_with_sections(config_path, {"memory": {"enabled": False}})

    monkeypatch.setenv("DEER_FLOW_CONFIG_PATH", str(config_path))
    monkeypatch.setenv("DEER_FLOW_EXTENSIONS_CONFIG_PATH", str(extensions_path))
    reset_app_config()

    try:
        get_app_config()
        assert get_memory_config().enabled is False

        _write_config_with_sections(config_path, {"memory": {"enabled": True}})
        next_mtime = config_path.stat().st_mtime + 5
        os.utime(config_path, (next_mtime, next_mtime))

        assert get_memory_config().enabled is True
    finally:
        _reset_config_singletons()


def test_get_memory_config_falls_back_on_broken_config(tmp_path, monkeypatch):
    """get_memory_config() does not crash on transiently broken config.yaml.

    get_app_config() can raise yaml.YAMLError, ValidationError, or ValueError.
    get_memory_config() catches them and returns the last-good singleton.
    """
    config_path = tmp_path / "config.yaml"
    extensions_path = tmp_path / "extensions_config.json"
    _write_extensions_config(extensions_path)

    _write_config_with_sections(config_path, {"memory": {"enabled": False}})

    monkeypatch.setenv("DEER_FLOW_CONFIG_PATH", str(config_path))
    monkeypatch.setenv("DEER_FLOW_EXTENSIONS_CONFIG_PATH", str(extensions_path))
    reset_app_config()

    try:
        get_app_config()
        assert get_memory_config().enabled is False

        config_path.write_text("memory: {enabled: true\n")
        next_mtime = config_path.stat().st_mtime + 5
        os.utime(config_path, (next_mtime, next_mtime))

        assert get_memory_config().enabled is False
    finally:
        _reset_config_singletons()