Add certificate validity to prometheus node exporter

files/certificate-validity.sh

@@ -0,0 +1,12 @@
+#!/bin/bash 
+
+rm -f /var/lib/prometheus/node-exporter/certs.prom
+
+for f in /etc/certs/*; do
+	snapshot_timestamp=$(openssl x509 -noout -enddate -in $f/cert.pem | cut -d= -f2)
+	snapshot_secs=$(date --date "$snapshot_timestamp" +%s)
+	now=$(date +%s)
+	delta=$((snapshot_secs - now))
+	name=$(echo $f | cut -d/ -f4)
+	printf 'certificate_validity{label="%s"} %s\n' $name $delta >> /var/lib/prometheus/node-exporter/certs.prom
+done

tasks/main.yml

@@ -95,3 +95,18 @@
   register: install_cert_result
   changed_when: cert_result.results[domains_index].changed
   failed_when: install_cert_result.rc != 0 and "Reload error for" not in install_cert_result.stderr
+
+- name: Place monitoring script
+  become: yes
+  copy:
+    src: files/certificate-validity.sh
+    dest: /root/.acme.sh/certificate-validity.sh
+    mode: 0700
+
+- name: Ensure monitoring data is updated
+  become: yes
+  cron:
+    name: "Update monitoring data each minute"
+    minute: "*/10"
+    hour: "*"
+    job: "/root/.acme.sh/certificate-validity.sh"