feat: compute load balancer targets status using a filter (#550)

##### SUMMARY

Allow to compute the status of a load balancer using a filter.

Closes #467 

##### ISSUE TYPE

- Feature Pull Request


##### COMPONENT NAME

hetzner.hcloud.loab_balancer_status

changelogs/fragments/load-balancer-status-filter.yml

@@ -0,0 +1,2 @@
+minor_changes:
+  - load_balancer_status - Add new filter to compute the status of a Load Balancer based on its targets.

plugins/filter/all.py

@@ -0,0 +1,49 @@
+from __future__ import annotations
+
+from typing import Literal
+
+from ansible.errors import AnsibleFilterError
+from ansible.module_utils.common.text.converters import to_native
+
+
+# pylint: disable=unused-argument
+def load_balancer_status(load_balancer: dict, *args, **kwargs) -> Literal["unknown", "unhealthy", "healthy"]:
+    """
+    Return the status of a Load Balancer based on its targets.
+    """
+    try:
+        result = "healthy"
+        for target in load_balancer["targets"]:
+            target_health_status = target.get("health_status")
+
+            # Report missing health status as unknown
+            if not target_health_status:
+                result = "unknown"
+                continue
+
+            for health_status in target_health_status:
+                status = health_status.get("status")
+                if status == "healthy":
+                    continue
+
+                if status in (None, "unknown"):
+                    result = "unknown"
+                    continue
+
+                if status == "unhealthy":
+                    return "unhealthy"
+
+        return result
+    except Exception as exc:
+        raise AnsibleFilterError(f"load_balancer_status - {to_native(exc)}", orig_exc=exc) from exc
+
+
+class FilterModule:
+    """
+    Hetzner Cloud filters.
+    """
+
+    def filters(self):
+        return {
+            "load_balancer_status": load_balancer_status,
+        }

plugins/filter/load_balancer_status.yml

@@ -0,0 +1,19 @@
+DOCUMENTATION:
+  name: load_balancer_status
+  version_added: 4.2.0
+  short_description: Compute the status of a Load Balancer
+  description:
+    - Compute the status of a Load Balancer based on its targets.
+  options:
+    _input:
+      description: Load Balancer data.
+      type: dict
+      required: true
+EXAMPLES: |
+  # Ensure a load balancer is healthy
+  {{ result.hcloud_load_balancer_info[0] | hetzner.hcloud.load_balancer_status == "healthy" }}
+
+RETURN:
+  _value:
+    description: The status of the Load Balancer targets, can be one of C(unknown), C(unhealthy) or C(healthy).
+    type: string

plugins/modules/load_balancer.py

@@ -104,11 +104,6 @@ hcloud_load_balancer:
             returned: always
             type: str
             sample: my-Load-Balancer
-        status:
-            description: Status of the Load Balancer
-            returned: always
-            type: str
-            sample: running
         load_balancer_type:
             description: Name of the Load Balancer type of the Load Balancer
             returned: always

plugins/modules/load_balancer_info.py

@@ -64,11 +64,6 @@ hcloud_load_balancer_info:
             returned: always
             type: str
             sample: my-Load-Balancer
-        status:
-            description: Status of the Load Balancer
-            returned: always
-            type: str
-            sample: running
         load_balancer_type:
             description: Name of the Load Balancer type of the Load Balancer
             returned: always

tests/integration/targets/filter_all/aliases

@@ -0,0 +1,3 @@
+cloud/hcloud
+gather_facts/no
+azp/group2

tests/integration/targets/filter_all/defaults/main/common.yml

@@ -0,0 +1,29 @@
+#
+# DO NOT EDIT THIS FILE! Please edit the files in tests/integration/common instead.
+#
+---
+# Azure Pipelines will configure this value to something similar to
+# "azp-84824-1-hetzner-2-13-test-2-13-hcloud-3-9-1-default-i"
+hcloud_prefix: "tests"
+
+# Used to namespace resources created by concurrent test pipelines/targets
+hcloud_run_ns: "{{ hcloud_prefix | md5 }}"
+hcloud_role_ns: "{{ role_name | split('_') | map('batch', 2) | map('first') | flatten() | join() }}"
+hcloud_ns: "ansible-{{ hcloud_run_ns }}-{{ hcloud_role_ns }}"
+
+# Used to easily update the server types and images across all our tests.
+hcloud_server_type_name: cax11
+hcloud_server_type_id: 45
+
+hcloud_server_type_upgrade_name: cax21
+hcloud_server_type_upgrade_id: 93
+
+hcloud_image_name: debian-12
+hcloud_image_id: 114690389 # architecture=arm
+
+hcloud_location_name: hel1
+hcloud_location_id: 3
+hcloud_datacenter_name: hel1-dc2
+hcloud_datacenter_id: 3
+
+hcloud_network_zone_name: eu-central

tests/integration/targets/filter_all/tasks/main.yml

@@ -0,0 +1,31 @@
+#
+# DO NOT EDIT THIS FILE! Please edit the files in tests/integration/common instead.
+#
+---
+- name: Check if cleanup.yml exists
+  ansible.builtin.stat:
+    path: "{{ role_path }}/tasks/cleanup.yml"
+  register: cleanup_file
+
+- name: Check if prepare.yml exists
+  ansible.builtin.stat:
+    path: "{{ role_path }}/tasks/prepare.yml"
+  register: prepare_file
+
+- name: Include cleanup tasks
+  ansible.builtin.include_tasks: "{{ role_path }}/tasks/cleanup.yml"
+  when: cleanup_file.stat.exists
+
+- name: Include prepare tasks
+  ansible.builtin.include_tasks: "{{ role_path }}/tasks/prepare.yml"
+  when: prepare_file.stat.exists
+
+- name: Run tests
+  block:
+    - name: Include test tasks
+      ansible.builtin.include_tasks: "{{ role_path }}/tasks/test.yml"
+
+  always:
+    - name: Include cleanup tasks
+      ansible.builtin.include_tasks: "{{ role_path }}/tasks/cleanup.yml"
+      when: cleanup_file.stat.exists

tests/integration/targets/filter_all/tasks/test.yml

@@ -0,0 +1,21 @@
+- name: Test filter load_balancer_status
+  block:
+    - name: Load data
+      ansible.builtin.set_fact:
+        load_balancer_status_healthy: >-
+          {{ { "targets": [
+            {"health_status": [{"status": "healthy"}]},
+            {"health_status": [{"status": "healthy"}]},
+          ]} | hetzner.hcloud.load_balancer_status }}
+
+        load_balancer_status_healthy_and_unhealthy: >-
+          {{ { "targets": [
+            {"health_status": [{"status": "healthy"}, {"status": "unhealthy"}]},
+            {"health_status": [{"status": "healthy"}, {"status": "healthy"}]},
+          ]} | hetzner.hcloud.load_balancer_status }}
+
+    - name: Verify filter load_balancer_status
+      ansible.builtin.assert:
+        that:
+          - load_balancer_status_healthy == "healthy"
+          - load_balancer_status_healthy_and_unhealthy == "unhealthy"

tests/unit/filter/test_all.py

@@ -0,0 +1,45 @@
+from __future__ import annotations
+
+import pytest
+
+from plugins.filter.all import load_balancer_status
+
+LOAD_BALANCER_STATUS_TEST_CASES = (
+    ({"targets": [{"health_status": []}]}, "unknown"),
+    ({"targets": [{"health_status": [{}]}]}, "unknown"),
+    ({"targets": [{"health_status": [{"status": "unknown"}]}]}, "unknown"),
+    ({"targets": [{"health_status": [{"status": "unhealthy"}]}]}, "unhealthy"),
+    ({"targets": [{"health_status": [{"status": "healthy"}]}]}, "healthy"),
+    (
+        {
+            "targets": [
+                {"health_status": [{"status": "healthy"}]},
+                {"health_status": [{"status": "healthy"}]},
+            ]
+        },
+        "healthy",
+    ),
+    (
+        {
+            "targets": [
+                {"health_status": [{"status": "healthy"}, {"status": "unhealthy"}]},
+                {"health_status": [{"status": "healthy"}, {"status": "unknown"}]},
+            ]
+        },
+        "unhealthy",
+    ),
+    (
+        {
+            "targets": [
+                {"health_status": [{"status": "healthy"}]},
+                {"health_status": [{"status": "unhealthy"}]},
+            ]
+        },
+        "unhealthy",
+    ),
+)
+
+
+@pytest.mark.parametrize(("value", "expected"), LOAD_BALANCER_STATUS_TEST_CASES)
+def test_load_balancer_status(value, expected):
+    assert expected == load_balancer_status(value)