refactor(deploy): use HAProxy admin socket instead of stats HTTP API

deploy/ansible/roles/app/tasks/main.yml

@@ -217,12 +217,11 @@
         docker kill -s HUP rustyip-haproxy
       changed_when: true
 
-    - name: Force new backend out of maintenance via stats admin
+    - name: Force new backend out of maintenance via admin socket
       ansible.builtin.shell: |
         sleep 1
-        docker exec rustyip-haproxy wget -qO- \
-          --post-data='s=app/{{ deploy_target }}&action=ready' \
-          "http://127.0.0.1:9000/stats" 2>/dev/null
+        docker exec rustyip-haproxy sh -c \
+          'echo "set server app/{{ deploy_target }} state ready" | socat stdio unix:/var/run/haproxy/admin.sock'
       changed_when: true
 
     - name: Wait for new backend to be UP in HAProxy
@@ -282,12 +281,11 @@
       changed_when: true
       failed_when: false
 
-    - name: Force original backend out of maintenance via stats admin
+    - name: Force original backend out of maintenance via admin socket
       ansible.builtin.shell: |
         sleep 1
-        docker exec rustyip-haproxy wget -qO- \
-          --post-data='s=app/{{ current_active }}&action=ready' \
-          "http://127.0.0.1:9000/stats" 2>/dev/null
+        docker exec rustyip-haproxy sh -c \
+          'echo "set server app/{{ current_active }} state ready" | socat stdio unix:/var/run/haproxy/admin.sock'
       changed_when: true
       failed_when: false
 

deploy/ansible/roles/app/templates/docker-compose.yml.j2

@@ -9,6 +9,7 @@ services:
       - ./haproxy/haproxy.cfg:/usr/local/etc/haproxy/haproxy.cfg:ro
       - ./haproxy/ipv4_domain.lst:/usr/local/etc/haproxy/ipv4_domain.lst:ro
       - ./haproxy/certs:/etc/haproxy/certs:ro
+      - haproxy_run:/var/run/haproxy
 {% if ipv4_domain %}
       - ./haproxy/certs-ipv4:/etc/haproxy/certs-ipv4:ro
 {% endif %}
@@ -64,6 +65,7 @@ services:
       - internal
 
 volumes:
+  haproxy_run:
   db_data_blue:
   db_data_green:
 

deploy/ansible/roles/app/templates/haproxy.cfg.j2

@@ -1,6 +1,7 @@
 global
     log stderr local0 err
     maxconn 10000
+    stats socket /var/run/haproxy/admin.sock mode 660 level admin
     # Performance tuning for high-throughput
     tune.bufsize 16384
     tune.maxrewrite 1024
@@ -137,7 +138,6 @@ frontend stats_internal
     stats enable
     stats uri /stats
     stats refresh 2s
-    stats admin if TRUE
 
 resolvers docker_dns
     nameserver dns1 127.0.0.11:53