Add new waiter (#306)

Add new waiter

SUMMARY

This refactors the waiter logic from common.py into a separate module.

ISSUE TYPE

COMPONENT NAME

ADDITIONAL INFORMATION

Reviewed-by: None <None>
Reviewed-by: Alina Buzachis <None>
Reviewed-by: None <None>

tests/unit/module_utils/test_waiter.py

@@ -0,0 +1,114 @@
+import os
+import time
+from pathlib import Path
+from unittest.mock import Mock
+
+import pytest
+import yaml
+from kubernetes.dynamic.resource import ResourceInstance
+from kubernetes.dynamic.exceptions import NotFoundError
+
+from ansible_collections.kubernetes.core.plugins.module_utils.k8s.waiter import (
+    clock,
+    custom_condition,
+    deployment_ready,
+    DummyWaiter,
+    exists,
+    get_waiter,
+    pod_ready,
+    resource_absent,
+    Waiter,
+)
+
+
+def resources(filepath):
+    current = Path(os.path.dirname(os.path.abspath(__file__)))
+    with open(current / filepath) as fp:
+        return [ResourceInstance(None, d) for d in yaml.safe_load_all(fp)]
+
+
+RESOURCES = resources("fixtures/definitions.yml")
+PODS = resources("fixtures/pods.yml")
+DEPLOYMENTS = resources("fixtures/deployments.yml")
+
+
+def test_clock_times_out():
+    start = time.monotonic()
+    for x in clock(5, 1):
+        pass
+    elapsed = int(time.monotonic() - start)
+    assert x == 5
+    assert 5 <= elapsed <= 6
+
+
+@pytest.mark.parametrize(
+    "resource,expected",
+    zip(RESOURCES + [None, {}], [True, True, True, False, False, False]),
+)
+def test_exists_and_absent_checks_for_existence(resource, expected):
+    assert exists(resource) is expected
+    assert resource_absent(resource) is not expected
+
+
+@pytest.mark.parametrize("pod,expected", zip(PODS, [True, False, True, True]))
+def test_pod_ready_checks_readiness(pod, expected):
+    assert pod_ready(pod) is expected
+
+
+@pytest.mark.parametrize("pod,expected", zip(PODS, [True, False, False, False]))
+def test_custom_condition_checks_readiness(pod, expected):
+    condition = {"type": "www.example.com/gate", "status": "True"}
+    assert custom_condition(condition, pod) is expected
+
+
+@pytest.mark.parametrize("deployment,expected", zip(DEPLOYMENTS, [True, False]))
+def test_deployment_ready_checks_readiness(deployment, expected):
+    assert deployment_ready(deployment) is expected
+
+
+def test_dummywaiter_returns_resource_immediately():
+    resource = {
+        "kind": "Pod",
+        "apiVersion": "v1",
+        "metadata": {"name": "foopod", "namespace": "foobar"},
+    }
+    result, instance, elapsed = DummyWaiter().wait(resource, 10, 100)
+    assert result is True
+    assert instance == resource
+    assert elapsed == 0
+
+
+def test_waiter_waits_for_missing_resource():
+    spec = {"get.side_effect": NotFoundError(Mock())}
+    client = Mock(**spec)
+    resource = Mock()
+    result, instance, elapsed = Waiter(client, resource, exists).wait(
+        RESOURCES[0], 3, 1
+    )
+    assert result is False
+    assert instance is None
+    assert abs(elapsed - 3) <= 1
+
+
+@pytest.mark.parametrize("resource,expected", zip(RESOURCES, [True, True, True, False]))
+def test_waiter_waits_for_resource_to_exist(resource, expected):
+    result = resource.to_dict()
+    spec = {"get.side_effect": [NotFoundError(Mock()), resource, resource, resource]}
+    client = Mock(**spec)
+    success, instance, elapsed = Waiter(client, Mock(), exists).wait(result, 3, 1)
+    assert success is expected
+    assert instance == result
+    assert abs(elapsed - 2) <= 1
+
+
+def test_get_waiter_returns_correct_waiter():
+    assert get_waiter(Mock(), PODS[0]).predicate == pod_ready
+    waiter = get_waiter(Mock(), PODS[0], check_mode=True)
+    assert isinstance(waiter, DummyWaiter)
+    assert get_waiter(Mock(), PODS[0], state="absent").predicate == resource_absent
+    assert (
+        get_waiter(
+            Mock(), PODS[0], condition={"type": "Ready", "status": "True"}
+        ).predicate.func
+        == custom_condition
+    )