enhancement(mysqld_exporter): allows using multiple web listen addresses

Signed-off-by: Christian Krause <christian.krause@idiv.de>

roles/mysqld_exporter/molecule/alternative/molecule.yml

@@ -4,7 +4,9 @@ provisioner:
     group_vars:
       all:
         mysqld_exporter_binary_local_dir: "/tmp/mysqld_exporter-linux-amd64"
-        mysqld_exporter_web_listen_address: "127.0.0.1:8080"
+        mysqld_exporter_web_listen_address:
+          - '127.0.0.1:8080'
+          - '127.0.1.1:8080'
         mysqld_exporter_enabled_collectors:
           - slave_hosts
         mysqld_exporter_disabled_collectors:
@@ -18,4 +20,4 @@ provisioner:
         mysqld_exporter_basic_auth_users:
           randomuser: examplepassword
         go_arch: amd64
-        mysqld_exporter_version: 0.13.0
+        mysqld_exporter_version: 0.15.0

roles/mysqld_exporter/molecule/alternative/tests/test_alternative.py

@@ -3,6 +3,7 @@ __metaclass__ = type
 
 import os
 import testinfra.utils.ansible_runner
+import pytest
 
 testinfra_hosts = testinfra.utils.ansible_runner.AnsibleRunner(
     os.environ['MOLECULE_INVENTORY_FILE']).get_hosts('all')
@@ -21,10 +22,9 @@ def test_service(host):
         raise  # Re-raise the original assertion error
 
 
-def test_socket(host):
-    sockets = [
-        "tcp://127.0.0.1:8080"
-    ]
-    for socket in sockets:
-        s = host.socket(socket)
-        assert s.is_listening
+@pytest.mark.parametrize("sockets", [
+    "tcp://127.0.0.1:8080",
+    "tcp://127.0.1.1:8080",
+])
+def test_socket(host, sockets):
+    assert host.socket(sockets).is_listening

roles/mysqld_exporter/tasks/preflight.yml

@@ -20,10 +20,26 @@
   ansible.builtin.package_facts:
   when: "not 'packages' in ansible_facts"
 
+- name: Assert that used version supports listen address type
+  ansible.builtin.assert:
+    that:
+      - >-
+        mysqld_exporter_web_listen_address is string
+        or
+        (
+          mysqld_exporter_version is version('0.15.0', '>=') and
+          mysqld_exporter_web_listen_address | type_debug == "list"
+        )
+
 - name: Naive assertion of proper listen address
   ansible.builtin.assert:
     that:
-      - "':' in mysqld_exporter_web_listen_address"
+      - >-
+        [mysqld_exporter_web_listen_address] |
+          flatten |
+          reject('match', '.+:\\d+$') |
+          list |
+          length == 0
 
 - name: Assert collectors are not both disabled and enabled at the same time
   ansible.builtin.assert:

roles/mysqld_exporter/templates/mysqld_exporter.service.j2

@@ -26,7 +26,16 @@ ExecStart={{ mysqld_exporter_binary_install_dir }}/mysqld_exporter \
 {% if mysqld_exporter_tls_server_config | length > 0 or mysqld_exporter_http_server_config | length > 0 or mysqld_exporter_basic_auth_users | length > 0 %}
     --web.config.file={{ mysqld_exporter_config_dir }}/web_config.yaml \
 {% endif %}
+{% if mysqld_exporter_version is version('0.15.0', '>=') and
+      mysqld_exporter_web_listen_address is iterable and
+      mysqld_exporter_web_listen_address is not mapping and
+      mysqld_exporter_web_listen_address is not string %}
+{%   for address in mysqld_exporter_web_listen_address %}
+    --web.listen-address={{ address }} \
+{%   endfor %}
+{% else %}
     --web.listen-address={{ mysqld_exporter_web_listen_address }} \
+{% endif %}
     --web.telemetry-path={{ mysqld_exporter_web_telemetry_path }} \
     --config.my-cnf={{ mysqld_exporter_config_dir }}/{{ mysqld_exporter_config_file }}