From ce3c77b62a2b7c82c612ef2364f8d488cb9556f8 Mon Sep 17 00:00:00 2001
From: Ricardo Pardini <ricardo@pardini.net>
Date: Sun, 14 Feb 2021 14:18:38 +0100
Subject: [PATCH] trying to make ipv6 actually work

---
 entrypoint.sh | 20 ++++++++++++++++++--
 1 file changed, 18 insertions(+), 2 deletions(-)

diff --git a/entrypoint.sh b/entrypoint.sh
index 1be0abe..7a7aa2c 100644
--- a/entrypoint.sh
+++ b/entrypoint.sh
@@ -4,12 +4,28 @@ set -Eeuo pipefail
 trap "echo TRAPed signal" HUP INT QUIT TERM
 
 #configure nginx DNS settings to match host, why must we do that nginx?
-conf="resolver $(/usr/bin/awk 'BEGIN{ORS=" "} $1=="nameserver" {print $2}' /etc/resolv.conf);"
-[ "$conf" = "resolver ;" ] && echo "no nameservers found" && exit 0
+export RESOLVERS=$(awk '$1 == "nameserver" {print ($2 ~ ":")? "["$2"]": $2}' ORS=' ' /etc/resolv.conf | sed 's/ *$//g')
+if [ "x$RESOLVERS" = "x" ]; then
+    echo "Warning: unable to determine DNS resolvers for nginx" >&2
+    exit 66
+fi
+
+echo "DEBUG, determined RESOLVERS from /etc/resolv.conf: '$RESOLVERS'"
+
+conf=""
+for ONE_RESOLVER in ${RESOLVERS}; do
+	echo "Possible resolver: $ONE_RESOLVER"
+	conf="resolver $ONE_RESOLVER; "
+done
+
+echo "Final chosen resolver: $conf"
 confpath=/etc/nginx/resolvers.conf
 if [ ! -e $confpath ] || [ "$conf" != "$(cat $confpath)" ]
 then
+    echo "Using auto-determined resolver '$conf' via '$confpath'"
     echo "$conf" > $confpath
+else
+    echo "Not using resolver config, keep existing '$confpath' -- mounted by user?"
 fi
 
 # The list of SAN (Subject Alternative Names) for which we will create a TLS certificate.