add prometheus role

roles/prometheus/templates/nginx.conf.j2

@@ -0,0 +1,79 @@
+# {{ ansible_managed }}
+
+upstream prometheus_backend {
+    server 127.0.0.1:{{ prometheus_port }};
+}
+
+upstream alertmanager_backend {
+    server 127.0.0.1:{{ alertmanager_port }};
+}
+
+upstream karma_backend {
+    server 127.0.0.1:{{ karma_port }};
+}
+
+server {
+    listen 80;
+{% if ansible_all_ipv6_addresses | length %}
+    listen [::]:80;
+{% endif %}
+    server_name {{ prometheus_hostname }};
+
+    access_log /var/log/nginx/prometheus.access.log main;
+    error_log /var/log/nginx/prometheus.error.log warn;
+
+    location /.well-known/acme-challenge/ {
+        root /var/www/html;
+        try_files $uri =404;
+    }
+
+{% if prometheus_ssl_enabled is defined and
+      prometheus_ssl_enabled %}
+    location / {
+        return 301 https://$server_name$request_uri;
+    }
+{% endif %}
+}
+
+{% if prometheus_ssl_enabled is defined and
+      prometheus_ssl_enabled %}
+server {
+    listen 443 ssl http2;
+{% if ansible_all_ipv6_addresses | length %}
+    listen [::]:443 ssl http2;
+{% endif %}
+    server_name {{ prometheus_hostname }};
+
+    auth_basic           "Prometheus";
+    auth_basic_user_file {{ prometheus_htpasswd_path }};
+
+    access_log /var/log/nginx/prometheus.access.log main;
+    error_log /var/log/nginx/prometheus.error.log warn;
+
+{% if prometheus_ssl_certificate is defined %}
+    ssl_certificate {{ prometheus_ssl_certificate }};
+{% endif %}
+{% if prometheus_ssl_certificate_key is defined %}
+    ssl_certificate_key {{ prometheus_ssl_certificate_key }};
+{% endif %}
+{% if prometheus_ssl_dhparam is defined %}
+    ssl_dhparam {{ prometheus_ssl_dhparam }};
+{% endif %}
+
+    location /prometheus/ {
+        proxy_pass http://prometheus_backend/;
+    }
+
+    location /alertmanager/ {
+        proxy_pass http://alertmanager_backend/;
+    }
+
+    location /karma/ {
+        proxy_pass http://karma_backend/;
+    }
+
+    location / {
+        return 301 /prometheus/;
+    }
+}
+{% endif %}

roles/prometheus/templates/prometheus.service.j2

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+{{ ansible_managed | comment }}
+
+[Unit]
+Description=Prometheus
+After=network-online.target
+
+[Service]
+Type=simple
+User={{ prometheus_user }}
+Group={{ prometheus_group }}
+ExecReload=/bin/kill -HUP $MAINPID
+ExecStart={{ prometheus_bin_path }}/prometheus \
+  --config.file={{ prometheus_etc_path }}/prometheus.yaml \
+  --storage.tsdb.path={{ prometheus_var_path }} \
+{% if prometheus_web_external_url %}
+  --web.external-url={{ prometheus_web_external_url }} \
+{% endif %}
+{% if prometheus_web_route_prefix %}
+  --web.route-prefix={{ prometheus_web_route_prefix }} \
+{% endif %}
+{% if prometheus_web_listen_address %}
+  --web.listen-address={{ prometheus_web_listen_address }} \
+{% endif %}
+{% if prometheus_web_enable_lifecycle %}
+  --web.enable-lifecycle \
+{% endif %}
+{% if prometheus_storage_tsdb_min_block_duration %}
+  --storage.tsdb.min-block-duration={{ prometheus_storage_tsdb_min_block_duration }} \
+{% endif %}
+{% if prometheus_storage_tsdb_max_block_duration %}
+  --storage.tsdb.max-block-duration={{ prometheus_storage_tsdb_max_block_duration }} \
+{% endif %}
+
+[Install]
+WantedBy=multi-user.target

roles/prometheus/templates/targets.yaml.j2

@@ -0,0 +1 @@
+---