promtail: Support metrics scraping

templates/node-scraper.j2

@@ -90,6 +90,28 @@
 {% endfor %}
 {% endif %}
 
+{% if prometheus_agent.scrapers[item].promtail|d(False) and prometheus_agent.agents.promtail.enable %}
+- job_name: "prometheus-agent - promtail : {{ inventory_hostname }}"
+  scheme: https
+{% for i in ['scrape_timeout', 'scrape_interval'] if prometheus_agent[i] %}
+  {{ i }}: {{ prometheus_agent[i] }}
+{% endfor %}
+  static_configs:
+  - targets:
+    - {{ inventory_hostname }}:{{ prometheus_agent.scrapers[item].promtail }}
+    labels: {{ merged_prometheus_labels|to_json }}
+  tls_config:
+    ca_file: /etc/prometheus/targetcerts/{{ inventory_hostname }}.crt
+    cert_file: /etc/ssl/prometheus_scraper.crt
+    key_file: /etc/ssl/private/prometheus_scraper.key
+  relabel_configs:
+  - source_labels: [__address__]
+    regex: '([^:]+):\d+'
+    target_label: instance
+  - replacement: 'promtail'
+    target_label: job
+{% endif %}
+
 {% for j in prometheus_agent.scrapers[item].proxy|d({}) %}
 - job_name: "prometheus-agent - proxy - {{ j }} : {{ inventory_hostname }}"
   scheme: https