procurement-ingest/tests/test_api_handlers.py

"""procurement-api handler tests (offline, fake Dynamo).

Pins the auth seam both ways: docs routes fail closed on the shared token
(including the browser ?token= shim), while data routes must NOT consult the
token at all -- SigV4 authorization is API Gateway's job upstream, and a
handler-side token check there would break every legitimate SigV4 caller.
Also pins routing, 404/501/400 mapping, Decimal-safe serialization, and limit
clamping.
"""

import json
from decimal import Decimal

import pytest

from tests.support import load_lambda_module


class _FakeTable:
    def __init__(self, items):
        self._items = items
        self.last_kwargs = None

    def scan(self, **kwargs):
        self.last_kwargs = kwargs
        return {"Items": list(self._items)}

    def query(self, **kwargs):
        self.last_kwargs = kwargs
        return {"Items": list(self._items)}

    def get_item(self, Key):  # noqa: N803 (boto3 kwarg name)
        pk_attr, pk_val = next(iter(Key.items()))
        for item in self._items:
            if item.get(pk_attr) == pk_val:
                return {"Item": item}
        return {}


class _FakeDynamo:
    def __init__(self, tables):
        self.tables = tables

    def Table(self, name):  # noqa: N802 (boto3 method name)
        return self.tables[name]


def _event(method, resource, path_params=None, qs=None, headers=None):
    return {
        "httpMethod": method,
        "resource": resource,
        "pathParameters": path_params or {},
        "queryStringParameters": qs or {},
        "headers": headers or {},
    }


@pytest.fixture()
def api(monkeypatch):
    mod = load_lambda_module("api", "handler")
    wo_items = [
        {
            "work_order_id": "11144580730",
            "wo_status": "assigned",
            "description": "Dock door 14",
        }
    ]
    comment_items = [
        {
            "work_order_id": "11144580730",
            "comment_id": "11144580730#2026-01-01T00:00:00#abc123def456",
            "text": "Vendor dispatched",
        }
    ]
    po_items = [
        {
            "po_number": "2D-22030794",
            "total_amount": Decimal("123.45"),
            "line_items": [{"quantity": Decimal("5"), "price": Decimal("24.69")}],
        }
    ]
    site_items = [{"siteCode": "JFK8", "state": "NY", "poCount": Decimal("7")}]

    tables = {
        mod.wo_repo.WORK_ORDERS_TABLE: _FakeTable(wo_items),
        mod.wo_repo.COMMENTS_TABLE: _FakeTable(comment_items),
        mod.po_repo.PO_TABLE: _FakeTable(po_items),
        mod.po_repo.VERIFIED_SITES_TABLE: _FakeTable(site_items),
    }
    fake = _FakeDynamo(tables)
    monkeypatch.setattr(mod.wo_repo, "dynamodb", fake)
    monkeypatch.setattr(mod.po_repo, "dynamodb", fake)
    return mod, fake


def test_healthcheck_short_circuits(api):
    mod, _ = api
    assert mod.handler({"healthcheck": True}, None) == {"healthcheck": "ok"}


def test_docs_fail_closed_without_token(api):
    # No WEB_UI_AUTH_TOKEN_SECRET_ARN configured -> web_ui_auth returns None
    # -> the docs routes must 401, not serve the spec.
    mod, _ = api
    for resource in ("/docs", "/openapi.json"):
        response = mod.handler(_event("GET", resource), None)
        assert response["statusCode"] == 401


def test_docs_served_when_authenticated(api, monkeypatch):
    mod, _ = api
    monkeypatch.setattr(mod, "is_authenticated", lambda event: True)
    docs = mod.handler(_event("GET", "/docs"), None)
    assert docs["statusCode"] == 200
    assert docs["headers"]["Content-Type"].startswith("text/html")
    # Stock Swagger UI is inlined and the spec (carrying the title) with it.
    assert "SwaggerUIBundle" in docs["body"]
    assert "Procurement Ingest API" in docs["body"]
    # Every placeholder must be substituted, or the page renders broken.
    for placeholder in (
        mod._SPEC_PLACEHOLDER,
        mod._CSS_PLACEHOLDER,
        mod._JS_PLACEHOLDER,
        mod._PRESET_PLACEHOLDER,
    ):
        assert placeholder not in docs["body"]

    spec = mod.handler(_event("GET", "/openapi.json"), None)
    assert spec["statusCode"] == 200
    assert json.loads(spec["body"])["openapi"] == "3.1.0"


def test_token_query_shim_synthesizes_header(api, monkeypatch):
    mod, _ = api
    seen = {}

    def capture(event):
        seen.update(event.get("headers") or {})
        return False

    monkeypatch.setattr(mod, "is_authenticated", capture)
    original = _event("GET", "/docs", qs={"token": "sekrit"})
    mod.handler(original, None)
    assert seen.get("x-auth-token") == "sekrit"
    # The shim must not mutate the caller's event in place.
    assert "x-auth-token" not in original["headers"]


def test_non_ascii_token_fails_closed_not_500(api):
    # A non-ASCII presented token must 401 (fail closed), not crash
    # hmac.compare_digest into a 500 that pages the 5xx alarm. Reach the
    # web_ui_auth module namespace through the imported is_authenticated's
    # globals and seed a valid cached token.
    mod, _ = api
    auth_globals = mod.is_authenticated.__globals__
    auth_globals["_auth_token_cache"] = "correct-token"
    auth_globals["_auth_token_cached_at"] = float("inf")
    try:
        response = mod.handler(
            _event("GET", "/docs", headers={"x-auth-token": "é"}), None
        )
        assert response["statusCode"] == 401
    finally:
        auth_globals["_auth_token_cache"] = None
        auth_globals["_auth_token_cached_at"] = 0.0


def test_data_routes_never_consult_docs_token(api, monkeypatch):
    mod, _ = api

    def explode(event):
        raise AssertionError("data routes must not consult the docs token")

    monkeypatch.setattr(mod, "is_authenticated", explode)
    response = mod.handler(_event("GET", "/work-orders"), None)
    assert response["statusCode"] == 200


def test_list_and_get_routing(api):
    mod, _ = api
    listing = mod.handler(_event("GET", "/work-orders"), None)
    body = json.loads(listing["body"])
    assert body["items"][0]["work_order_id"] == "11144580730"
    assert body["next_cursor"] is None

    hit = mod.handler(
        _event(
            "GET",
            "/work-orders/{workOrderId}",
            path_params={"workOrderId": "11144580730"},
        ),
        None,
    )
    assert json.loads(hit["body"])["wo_status"] == "assigned"

    miss = mod.handler(
        _event(
            "GET",
            "/work-orders/{workOrderId}",
            path_params={"workOrderId": "999"},
        ),
        None,
    )
    assert miss["statusCode"] == 404

    comments = mod.handler(
        _event(
            "GET",
            "/work-orders/{workOrderId}/comments",
            path_params={"workOrderId": "11144580730"},
        ),
        None,
    )
    assert json.loads(comments["body"])["items"][0]["text"] == "Vendor dispatched"

    sites = mod.handler(
        _event(
            "GET",
            "/verified-sites/{siteCode}",
            path_params={"siteCode": "JFK8"},
        ),
        None,
    )
    assert json.loads(sites["body"])["state"] == "NY"


def test_decimal_serialization_round_trips(api):
    mod, _ = api
    response = mod.handler(
        _event(
            "GET",
            "/purchase-orders/{poNumber}",
            path_params={"poNumber": "2D-22030794"},
        ),
        None,
    )
    body = json.loads(response["body"])
    assert body["total_amount"] == 123.45
    assert body["line_items"][0]["quantity"] == 5
    assert isinstance(body["line_items"][0]["quantity"], int)
    assert "Decimal" not in response["body"]


def test_limit_clamped_to_bounds(api):
    mod, fake = api
    mod.handler(_event("GET", "/work-orders", qs={"limit": "9999"}), None)
    assert fake.tables[mod.wo_repo.WORK_ORDERS_TABLE].last_kwargs["Limit"] == 500
    mod.handler(_event("GET", "/work-orders", qs={"limit": "0"}), None)
    assert fake.tables[mod.wo_repo.WORK_ORDERS_TABLE].last_kwargs["Limit"] == 1


def test_non_integer_limit_is_400(api):
    mod, _ = api
    response = mod.handler(_event("GET", "/work-orders", qs={"limit": "abc"}), None)
    assert response["statusCode"] == 400


def test_planned_routes_return_501(api):
    mod, _ = api
    for method, resource in mod.PLANNED_ROUTES:
        response = mod.handler(_event(method, resource), None)
        assert response["statusCode"] == 501, (method, resource)


def test_unknown_route_is_404(api):
    mod, _ = api
    response = mod.handler(_event("GET", "/nope"), None)
    assert response["statusCode"] == 404


def test_unexpected_error_maps_to_clean_500(api, monkeypatch):
    mod, fake = api

    def boom(**kwargs):
        raise RuntimeError("dynamo fell over")

    monkeypatch.setattr(fake.tables[mod.wo_repo.WORK_ORDERS_TABLE], "scan", boom)
    response = mod.handler(_event("GET", "/work-orders"), None)
    assert response["statusCode"] == 500
    assert json.loads(response["body"]) == {"error": "internal error"}