add prometheus and grafana for monitoring

caddy/Caddyfile

+{
+    servers {
+        metrics
+    }
+}
+
 :80 {
+    metrics /metrics
     route / {                    
         reverse_proxy todolist:8080                           
     }

docker-compose.yml

@@ -4,3 +4,6 @@ include:
   - caddy/caddy.docker-compose.yml
   - todolist/todolist.docker-compose.yml
   - postgres/postgres.docker-compose.yml
+  - prometheus/prometheus.docker-compose.yml
+  - grafana/grafana.docker-compose.yml
+  - postgres-exporter/postgres-exporter.docker-compose.yml
\ No newline at end of file

grafana/grafana.docker-compose.yml

+services:
+  grafana:
+    image: grafana/grafana-oss
+    ports:
+      - 3000:3000
\ No newline at end of file

postgres-exporter/postgres-exporter.docker-compose.yml

+services:
+  postgres-exporter:
+    image: quay.io/prometheuscommunity/postgres-exporter
+    environment:
+      - DATA_SOURCE_NAME=postgres://user:password@postgres:5432/todo?sslmode=disable
\ No newline at end of file

prometheus/prometheus.docker-compose.yml

+services:
+  prometheus:
+    image: prom/prometheus
+    volumes:
+      - ./prometheus.yml:/etc/prometheus/prometheus.yml
+    ports:
+      - 9090:9090
\ No newline at end of file

prometheus/prometheus.yml

+global:
+  scrape_interval: 15s
+
+scrape_configs:
+  - job_name: caddy
+    static_configs:
+      - targets: ['caddy']
+  - job_name: postgres
+    static_configs:
+      - targets: ['postgres-exporter:9187']
\ No newline at end of file