promtail: Move hard-coded config to prometheus_agent.agents.promtail.config inventory key

templates/promtail.yml.j2

@@ -1,49 +1,8 @@
-server:
-  disable: true
-  http_listen_port: 9080
-  grpc_listen_port: 0
-
-positions:
-  filename: /var/lib/promtail/positions.yaml
-
-clients:
+{% if 'clients' not in prometheus_agent.agents.promtail.config %}
+{% set tmp = prometheus_agent.agents.promtail.config.setdefault('clients', []) %}
 {% for i in prometheus_agent.scrapers if prometheus_agent.scrapers[i].get("loki") %}
 {% set lokiconfig = {}|combine({ "external_labels": merged_prometheus_labels|combine( {"instance": inventory_hostname} ) }, prometheus_agent.scrapers[i]['loki'] ) %}
-  - {{ lokiconfig|to_json }}
+{% set tmp = prometheus_agent.agents.promtail.config.clients.append(lokiconfig) %}
 {% endfor %}
-
-scrape_configs:
-- job_name: system
-  static_configs:
-  - targets:
-      - localhost
-    labels:
-      job: varlogs
-      __path__: /var/log/*log
-- job_name: journal
-  journal:
-    max_age: 12h
-    labels:
-      job: systemd-journal
-  relabel_configs:
-    - source_labels: ['__journal__systemd_unit']
-      target_label: 'unit'
-    - source_labels: ['__journal_priority_keyword']
-      target_label: 'level'
-  pipeline_stages:
-    - structured_metadata:
-        level:
-- job_name: nginx
-  static_configs:
-  - targets:
-      - localhost
-    labels:
-      job: nginx
-      __path__: /var/log/nginx/access-promtail.log
-- job_name: postfix-bounces
-  static_configs:
-  - targets:
-      - localhost
-    labels:
-      job: postfix-bounces
-      __path__: /var/log/mailman3/bounce.log
+{% endif %}
+{{ prometheus_agent.agents.promtail.config|to_nice_yaml(indent=2) }}