Add a blackbox probe for public HTTPS

roles/prometheus/templates/blackbox.yml.j2

 modules:
 
+  # Healthcheck probe to use on internal targets.
   http_health:
     prober: http
     timeout: 5s
@@ -13,6 +14,25 @@ modules:
       preferred_ip_protocol: ip4
       tls_config:
         ca_file: /etc/credentials/x509/prometheus/ca.pem
+        cert_file: /etc/credentials/x509/prometheus/client/cert.pem
+        key_file: /etc/credentials/x509/prometheus/client/private_key.pem
+        insecure_skip_verify: false
+
+  # HTTP probe for the main public website.
+  http_public:
+    prober: http
+    timeout: 5s
+    http:
+      valid_status_codes: [200, 301, 302, 307]
+      method: GET
+      headers:
+        Host: "www.{{ domain_public[0] }}"
+      fail_if_ssl: false
+      fail_if_not_ssl: true
+      preferred_ip_protocol: ip4
+      tls_config:
+        server_name: "www.{{ domain_public[0] }}"
+        ca_file: /etc/ssl/certs/ca-certificates.crt
         insecure_skip_verify: false
 
   ping:

roles/prometheus/templates/prometheus.yml.j2

@@ -88,7 +88,7 @@ scrape_configs:
 {% endfor %}
 
 
-{# Blackbox prober configs: host targets (icmp) #}
+{# Blackbox probes #}
 {% for prober_host in groups['prometheus']|sort %}
 
   - job_name: "prober_ping_{{ loop.index }}"
@@ -120,7 +120,7 @@ scrape_configs:
   - job_name: "prober_https_{{ loop.index }}"
     metrics_path: "/probe"
     params:
-      module: [http_health]
+      module: [http_public]
     relabel_configs:
       - source_labels: [__address__]
         target_label: target
@@ -137,7 +137,7 @@ scrape_configs:
     static_configs:
       - targets:
 {% for host in groups['frontend']|sort %}
-        - "https://{{ host }}/healthcheck"
+        - "https://{{ host }}/"
 {% endfor %}
         labels:
           zone: public