Haproxy for flask-socketio

haproxy.conf

global
  daemon

defaults
  mode http
  log global
  option httplog
  option  http-server-close
  option  dontlognull
  option  redispatch
  option  contstats
  retries 3
  backlog 10000
#  timeout client          25s
#  timeout connect          5s
#  timeout server          25s
# timeout tunnel available in ALOHA 5.5 or HAProxy 1.5-dev10 and higher
  timeout tunnel        3600s
#  timeout http-keep-alive  1s
  timeout http-request    15s
#  timeout queue           30s
#  timeout tarpit          60s
  default-server inter 3s rise 2 fall 3
  option forwardfor


frontend ft_web
  mode tcp

  # To get the server.pem
  # fullchain.pem don't work because the privkey must come first
  # do "cat privkey.pem cert.pem > server.pem"
  bind *:8888 ssl crt /usr/local/etc/nginx/ssl/server.pem

  stats enable
  maxconn 10000
  acl hdr_connection_upgrade hdr(Connection)  -i upgrade
  acl hdr_upgrade_websocket  hdr(Upgrade)     -i websocket
  use_backend ws if hdr_connection_upgrade hdr_upgrade_websocket
  default_backend www

# To support the first Socket.io upgrading via polling (simple http api request)
backend www
  mode http
  cookie SIO insert
  balance roundrobin

  server websrv1 127.0.0.1:5001 maxconn 10000 weight 10 cookie websrv1
  #server websrv2 127.0.0.1:5002 maxconn 10000 weight 10 cookie websrv2

backend ws
  balance roundrobin 
  mode tcp
  cookie SIO insert

  ## websocket protocol validation
  acl hdr_connection_upgrade hdr(Connection)                 -i upgrade
  acl hdr_upgrade_websocket  hdr(Upgrade)                    -i websocket
  acl hdr_websocket_key      hdr_cnt(Sec-WebSocket-Key)      eq 1
  acl hdr_websocket_version  hdr_cnt(Sec-WebSocket-Version)  eq 1
  http-request deny if ! hdr_connection_upgrade ! hdr_upgrade_websocket ! hdr_websocket_key ! hdr_websocket_version

  ## ensure our application protocol name is valid
  ## (don't forget to update the list each time you publish new applications)
  ##  acl ws_valid_protocol hdr(Sec-WebSocket-Protocol) echo-protocol
  ##  http-request deny if ! ws_valid_protocol
  option forwardfor # This sets X-Forwarded-Forw

  server websrv1 127.0.0.1:5001 maxconn 10000 weight 10 cookie websrv1
  #server websrv2 127.0.0.1:5002 maxconn 10000 weight 10 cookie websrv2