Add healthcheck for haproxy

Author: YuryHrytsuk

services/rabbit/docker-compose.yml.j2

@@ -20,7 +20,13 @@ services:
         reservations:
           cpus: "0.1"
           memory: "128M"
-    # healthcheck: https://github.com/haproxy/haproxy/issues/3091
+    healthcheck: # https://stackoverflow.com/a/76513320/12124525
+      test: bash -c 'echo "" > /dev/tcp/127.0.0.1/32087 || exit 1'
+      start_period: 5s
+      timeout: 2s
+      retries: 2
+      interval: 10s
+
     networks:
       - rabbit
     configs:

services/rabbit/haproxy.cfg.j2

@@ -38,6 +38,11 @@ frontend rabbit_dashboard
     bind *:{{ RABBIT_MANAGEMENT_PORT }}
     default_backend rabbit_dashboard_backends
 
+frontend health
+  mode http
+  bind 127.0.0.1:32087
+  http-request return status 200 if { src 127.0.0.0/8 }
+
 backend rabbit_backends
     # side effect of roundrobin is connection should be evenly distributed
     # thus rabbit queue leader replica shall be also evenly distributed

services/rabbit/template.env

@@ -13,4 +13,3 @@ RABBIT_LB_REPLICAS=${RABBIT_LB_REPLICAS}
 RABBIT_NETWORK=${RABBIT_NETWORK}
 
 PUBLIC_NETWORK=${PUBLIC_NETWORK}
-MONITORING_DOMAIN=${MONITORING_DOMAIN}