k8s: check ssl expiration cronjob

k8s-check-ssl-expiration-cronjob.yaml

apiVersion: batch/v1
kind: CronJob
metadata:
  name: check-ssl-expiration
  namespace: default
spec:
  concurrencyPolicy: Allow
  failedJobsHistoryLimit: 1
  jobTemplate:
    spec:
      template:
        spec:
          containers:
          - command:
            - /bin/sh
            - -c
            - echo "today=\$(date +%Y-%m-%d);months=\"Jan Feb Mar Apr May Jun Jul
              Aug Sep Oct Nov Dec\";x=\$(echo -n \$1' ';curl --insecure -vvI https://\${1}
              2>&1 | awk 'BEGIN { cert=0 } /^\* SSL connection/ { cert=1 } /^\*/ {
              if (cert) print }' | grep expire|awk -F \":\" '{print \$2 \"\" \$4}'
              | awk '{print \$4\"-\"\$1\"-\"\$2}');month=\$(echo \$x | awk '{print
              \$2}' | awk -F '-' '{print \$2}');nummonth=\$(string=\"\${months%\$month*}\"
              && echo -n \"\$((\${#string}/4 + 1))\");entry=\$(echo -n \$x | awk -v
              ORS=\" \" '{print \$1}'; echo -n \$x | awk '{print \$2}' | awk -v ORS=\"\"
              -F '-' '{print \$1\"-\"}'; echo -n \$nummonth;echo -n \$x | awk '{print
              \$2}' | awk -F '-' '{print \"-\"\$3}');entrydate=\$(echo \$entry | awk
              '{print \$2}');echo \"\$x\";daysleft=\$(echo -n \$(date -d \"\$entrydate\"
              \+\%s 2>/dev/null) \$(date -d \"\$today\" \+\%s 2>/dev/null) | awk -v
              ORS=\"\" '{print (\$1 - \$2) / 86400}');if [ \"\$daysleft\" -le \"$daythreshold\"
              ]; then  curl -X POST --data '{\"text\":\"'\"The SSL certificate for
              https://\${1} will expire in \${daysleft} days!\"'\"}' $slackurl; fi"
              > /tmp/expires;chmod +x /tmp/expires;for DOMAIN in [ $check ]; do /tmp/expires
              $DOMAIN | grep -vE '\]|\[' >> list.txt; done;cat list.txt | awk '{print
              $2 " " $1}' | sort;rm -rf list.txt
            env:
            - name: check
              value: google.com github.com ipv4ip.com
            - name: daythreshold
              value: "31"
            - name: slackurl
              value: https://hooks.slack.com/services/xxxxxxxxx/xxxxxxxxxxx/xxxxxxxxxxxxxxxxxxxxxxxx
            image: curlimages/curl:8.2.0
            imagePullPolicy: IfNotPresent
            name: check-ssl-expiration
            terminationMessagePath: /dev/termination-log
            terminationMessagePolicy: File
          dnsPolicy: ClusterFirst
          restartPolicy: OnFailure
          schedulerName: default-scheduler
          terminationGracePeriodSeconds: 30
  schedule: 00 13 * * 1-5
  successfulJobsHistoryLimit: 1
  suspend: false