r/alertmanager: Deploy AlertManager

*AlertManager* is the component of the Prometheus ecosystem responsible
for sending alert notifications.

roles/alertmanager/handlers/main.yml

@@ -0,0 +1,4 @@
+- name: reload alertmanager
+  service:
+    name: alertmanager
+    state: reloaded

roles/alertmanager/tasks/deploy.yml

@@ -0,0 +1,36 @@
+- name: ensure prometheus configuration directory exists
+  file:
+    path: /etc/prometheus
+    mode: u=rwx,go=rx
+    owner: root
+    group: root
+    state: directory
+  tags:
+  - config
+- name: ensure alertmanager is configured
+  copy:
+    dest: /etc/prometheus/alertmanager.yml
+    content: |+
+      {{ alertmanager_config | to_nice_yaml(indent=2) }}
+    mode: u=rw,go=r
+    owner: root
+    group: root
+  notify:
+  - reload alertmanager
+  tags:
+  - config
+
+- name: ensure alertmanager starts at boot
+  service:
+    name: alertmanager
+    enabled: true
+  tags:
+  - service
+- name: flush handlers
+  meta: flush_handlers
+- name: ensure alertmanager is running
+  service:
+    name: alertmanager
+    state: started
+  tags:
+  - service

roles/alertmanager/tasks/main.yml

@@ -0,0 +1,7 @@
+- block:
+#  - import_tasks: install.yml
+#    tags:
+#    - install
+  - import_tasks: deploy.yml
+  tags:
+  - alertmanager