add docker-entrypoint.sh

Author: bigjust

docker-entrypoint.sh

@@ -0,0 +1,17 @@
+#!/bin/sh
+set -e
+
+# first arg is `-f` or `--some-option`
+if [ "${1#-}" != "$1" ]; then
+    set -- haproxy "$@"
+fi
+
+if [ "$1" = 'haproxy' ]; then
+    shift # "haproxy"
+    # if the user wants "haproxy", let's add a couple useful flags
+    #   -W  -- "master-worker mode" (similar to the old "haproxy-systemd-wrapper"; allows for reload via "SIGUSR2")
+    #   -db -- disables background mode
+    set -- haproxy -W -db "$@"
+fi
+
+exec "$@"