FabledSteward/tests/plugins/docker/test_mcp_tools.py

"""The docker plugin's MCP tools: what counts as a problem, and how it is reported."""
import inspect
from datetime import datetime, timedelta, timezone
from types import SimpleNamespace as NS
from unittest.mock import MagicMock

import pytest

import plugins.docker as docker_plugin
from plugins.docker import mcp_tools as t
from steward.models.users import UserRole

NOW = datetime(2026, 10, 6, 12, 0, tzinfo=timezone.utc)


def _c(**kw):
    base = dict(name="web", host_id="h1", image="nginx", status="running", health=None,
                exit_code=None, oom_killed=False, restart_count=0, cpu_pct=1.0, mem_pct=2.0,
                mem_usage_bytes=1, mem_limit_bytes=2, started_at=NOW - timedelta(hours=1),
                compose_project=None, service_name=None, scraped_at=NOW - timedelta(seconds=30))
    base.update(kw)
    return NS(**base)


def test_container_problems_most_severe_first():
    assert t.container_problems(_c(), 0, False) == []
    assert t.container_problems(_c(status="restarting"), 4, True) == ["restarting", "crash_looping"]
    # The crash-loop count comes from Settings → Thresholds.
    assert t.container_problems(_c(), 2, True) == []
    assert t.container_problems(_c(), 2, True, crash_loop_deaths=2) == ["crash_looping"]
    assert t.container_problems(_c(health="unhealthy", oom_killed=True), 0, False) == ["unhealthy", "oom_killed"]
    # An unhealthy flag on a stopped container is stale; it isn't failing a healthcheck now.
    assert t.container_problems(_c(status="exited", health="unhealthy", exit_code=0), 0, False) == []


def test_exited_nonzero_needs_a_recent_death():
    crashed = _c(status="exited", exit_code=1)
    assert t.container_problems(crashed, 1, True) == ["exited_nonzero"]
    # A container that died weeks ago and was left stopped is not news.
    assert t.container_problems(crashed, 0, False) == []


def test_a_stop_is_not_an_exit_failure():
    # 137 (SIGKILL) and 143 (SIGTERM) are how `docker stop` ends a container;
    # without an OOM kill that is someone stopping it, not it failing (#5209).
    for code in (137, 143):
        assert t.container_problems(_c(status="exited", exit_code=code), 1, True) == []
    oom = _c(status="exited", exit_code=137, oom_killed=True)
    assert t.container_problems(oom, 1, True) == ["oom_killed"]


def test_cut_middle_keeps_both_ends_and_sizes_the_gap():
    assert t.cut_middle("short") == "short"
    line = "A" * 10 + "B" * 100 + "C" * 10
    cut = t.cut_middle(line, limit=20)
    assert cut.startswith("A" * 10) and cut.endswith("C" * 10)
    assert "[… 100 characters omitted …]" in cut


def test_container_row_uptime_only_while_running():
    row = t.container_row(_c(), {"h1": "nas"}, [], NOW)
    assert row["host_name"] == "nas" and row["uptime_s"] == 3600 and row["reported_age_s"] == 30
    assert t.container_row(_c(status="exited"), {}, [], NOW)["uptime_s"] is None


def test_container_findings_one_per_container_with_every_problem_named():
    rows = [t.container_row(_c(name="db", status="restarting", exit_code=1), {"h1": "nas"},
                            ["restarting", "crash_looping"], NOW),
            t.container_row(_c(name="ok"), {}, [], NOW)]
    (f,) = t.container_findings(rows)
    assert f["severity"] == "critical" and f["kind"] == "container_restarting"
    assert "is restarting and keeps dying" in f["summary"] and "on nas" in f["summary"]
    assert "(exit 1)" in f["summary"]
    assert f["next"] == 'get_container(container="db", host="h1")'


def test_service_findings_by_state():
    svcs = [{"name": "a", "state": "healthy", "running": 2, "desired": 2},
            {"name": "b", "state": "degraded", "running": 1, "desired": 3},
            {"name": "c", "state": "down", "running": 0, "desired": 1}]
    got = {f["subject"]: f["severity"] for f in t.service_findings(svcs)}
    assert got == {"b": "warning", "c": "critical"}


def test_service_findings_name_the_crash_loop_and_swarms_error():
    err = {"error": "task: non-zero exit (1)", "message": "started", "state": "failed",
           "exit_code": 1, "node": "docker03"}
    svcs = [{"name": "db", "state": "down", "running": 0, "desired": 1, "crash_looping": True,
             "failures_1h": 4, "failures_24h": 5, "last_error": err},
            {"name": "app", "state": "down", "running": 0, "desired": 1, "crash_looping": False,
             "failures_1h": 0, "failures_24h": 0,
             "last_error": {"error": "No such image: app:dev", "state": "rejected",
                            "exit_code": None, "node": None, "message": None}},
            {"name": "web", "state": "healthy", "running": 2, "desired": 2, "crash_looping": False,
             "failures_1h": 0, "failures_24h": 1, "last_error": err},
            {"name": "ok", "state": "healthy", "running": 1, "desired": 1, "crash_looping": False,
             "failures_1h": 0, "failures_24h": 0, "last_error": None}]
    got = {f["subject"]: f for f in t.service_findings(svcs)}
    assert set(got) == {"db", "app"}     # web is back to all its replicas: history (#5722)
    db = got["db"]
    assert db["kind"] == "swarm_service_crash_looping" and db["severity"] == "critical"
    assert "4 tasks failed in the last hour" in db["summary"]
    assert "last task error: task: non-zero exit (1), exit 1 on docker03" in db["summary"]
    # Down without a loop still names why: here Swarm could not even start it.
    assert got["app"]["kind"] == "swarm_service_down"
    assert got["app"]["summary"].endswith("last task error: No such image: app:dev")


def test_a_replaced_swarm_task_is_marked_and_judged_on_its_service():
    task = _c(name="app.1.old", status="exited", exit_code=137, service_name="app")
    row = t.container_row(task, {}, [], NOW, replaced=True)
    assert row["swarm_replaced"] is True and row["problems"] == []
    assert t.container_row(_c(), {}, [], NOW)["swarm_replaced"] is None  # not a swarm task


def test_plugin_exposes_the_mcp_hooks():
    reg = MagicMock()
    docker_plugin.register_mcp_tools(reg)
    regs = {call.args[0].__name__: call.kwargs for call in reg.call_args_list}
    assert set(regs) == {"list_containers", "get_container", "list_swarm_services",
                         "search_container_logs", "get_docker_disk_usage", "prune_docker"}
    for name, kw in regs.items():
        if name == "prune_docker":
            assert (kw["role"], kw["read_only"]) == (UserRole.admin, False)
        else:
            assert (kw["role"], kw["read_only"]) == (UserRole.viewer, True), name
    assert callable(docker_plugin.mcp_overview)


def test_prune_preview_sizes_what_each_target_removes():
    usage = NS(images_reclaimable=3000, build_cache_size=70)
    assert t.prune_preview("containers", usage, 4) == {"stopped_containers": 4}
    assert t.prune_preview("images", usage, 4) == {"unused_images_bytes": 3000}
    system = t.prune_preview("system", usage, 4)
    assert system["stopped_containers"] == 4 and system["build_cache_bytes"] == 70
    assert t.prune_preview("images", None, 0) == {"unused_images_bytes": None}


async def test_prune_docker_refuses_an_unknown_target_before_reading_anything(monkeypatch):
    def _no_db():
        raise AssertionError("touched the database")
    monkeypatch.setattr(t, "db_session", _no_db)
    with pytest.raises(ValueError, match="'volumes' is not one of containers, images, system"):
        await t.prune_docker("nas", "volumes")
    assert inspect.signature(t.prune_docker).parameters["check"].default is True


def _death(event, minutes_ago):
    return NS(event=event, at=NOW - timedelta(minutes=minutes_ago))


def test_problem_since_dates_each_problem_from_its_own_evidence():
    hour_ago = NOW - timedelta(hours=1)
    deaths = [_death("die", 5), _death("die", 20), _death("die", 50), _death("die", 300)]
    # A crash loop began with its first death inside the hour, not the older one.
    assert t.problem_since(["crash_looping"], deaths, hour_ago) == NOW - timedelta(minutes=50)
    # An error exit dates from the death that ended it.
    assert t.problem_since(["exited_nonzero"], deaths, hour_ago) == NOW - timedelta(minutes=5)
    oom = [_death("die", 2), _death("oom", 3)]
    assert t.problem_since(["oom_killed", "exited_nonzero"], oom, hour_ago) == NOW - timedelta(minutes=3)
    turned = NOW - timedelta(hours=2)
    assert t.problem_since(["unhealthy"], [], hour_ago, turned) == turned
    # No retained evidence: unknown, not now.
    assert t.problem_since(["unhealthy"], [], hour_ago) is None
    assert t.problem_since([], deaths, hour_ago) is None


def test_findings_carry_when_the_problem_began():
    began = NOW - timedelta(minutes=40)
    row = t.container_row(_c(name="db", status="exited", exit_code=1), {}, ["exited_nonzero"],
                          NOW, since=began)
    assert row["problem_since"] == "2026-10-06T11:20:00Z" and row["problem_age_s"] == 2400
    (f,) = t.container_findings([row])
    assert f["since"] == "2026-10-06T11:20:00Z" and f["age_s"] is not None
    svc = {"name": "db", "state": "down", "running": 0, "desired": 1, "trouble_since": began}
    (g,) = t.service_findings([svc])
    assert g["since"] == "2026-10-06T11:20:00Z"


def test_services_that_failed_together_are_one_finding_and_recovered_ones_none():
    """#5722: nine services lost tasks within three minutes on one node's bad
    moment, and stayed on the overview for a day after they were back. Those
    back to full replicas are history; those still short and started together
    are one finding naming them, dated from the first."""
    at = NOW - timedelta(minutes=30)
    svcs = [{"name": "auth", "state": "degraded", "running": 1, "desired": 2, "trouble_since": at},
            {"name": "wiki", "state": "down", "running": 0, "desired": 1,
             "trouble_since": at + timedelta(minutes=2)},
            {"name": "later", "state": "degraded", "running": 1, "desired": 2,
             "trouble_since": at + timedelta(minutes=20)},
            {"name": "back", "state": "healthy", "running": 1, "desired": 1, "failures_24h": 3,
             "trouble_since": at}]
    together, alone = t.service_findings(svcs)
    assert together["kind"] == "swarm_services_short" and together["severity"] == "critical"
    assert together["subject"] == "2 swarm services"
    assert "auth (1 of 2 replicas running), wiki (0 of 1 replicas running)" in together["summary"]
    assert together["since"] == "2026-10-06T11:30:00Z"
    assert alone["subject"] == "later" and alone["kind"] == "swarm_service_degraded"


def _node(node_id, hostname, status="ready", availability="active", role="worker", minutes=0):
    return NS(node_id=node_id, hostname=hostname, status=status, availability=availability,
              role=role, leader=False, host_id="mgr",
              updated_at=datetime(2026, 10, 15, 12, 0, tzinfo=timezone.utc) - timedelta(minutes=minutes))


def test_unique_nodes_keep_the_newest_report_of_each():
    old, new = _node("n1", "a", status="down", minutes=5), _node("n1", "a")
    assert t.unique_nodes([old, new, _node("n2", "b")]) == [new, _node("n2", "b")]


def test_node_findings_name_a_down_node_unless_maintenance_is_rebooting_it():
    nodes = [_node("n1", "Web-1", status="down", role="manager"),
             _node("n2", "web-2", availability="drain"),       # kept drained on purpose (#5777)
             _node("n3", "web-3", status="unknown", availability="pause"),
             _node("n4", "web-4", availability="drain", status="down"),   # being rebooted
             _node("n5", "web-5")]
    out = {f["subject"]: f for f in t.node_findings(nodes, {"web-4": "rebooting"})}
    assert set(out) == {"Web-1", "web-3"}
    assert out["Web-1"]["severity"] == "critical" and out["Web-1"]["kind"] == "swarm_node_down"
    assert out["Web-1"]["summary"] == "swarm manager Web-1 is down"
    assert out["web-3"]["summary"] == "swarm worker web-3 is unknown and paused"
    # Once its job is over, the same node drained and down is named.
    [f] = t.node_findings([_node("n4", "web-4", availability="drain", status="down")], {})
    assert f["summary"] == "swarm worker web-4 is down and drained"