Improve indentation of generated nginx.conf (#2296)

rootfs/ingress-controller/clean-nginx-conf.sh

@@ -21,4 +21,7 @@
 # 1. remove the return carrier character/s
 # 2. remove empty lines
 # 3. replace multiple empty lines
-sed -e 's/\r//g' | sed -e 's/^  *$/\'$'\n/g' | sed -e '/^$/{N;/^\n$/D;}'
+
+SCRIPT_ROOT=$(dirname ${BASH_SOURCE})
+
+sed -e 's/\r//g' | sed -e 's/^  *$/\'$'\n/g' | sed -e '/^$/{N;/^\n$/D;}' | ${SCRIPT_ROOT}/indent.sh

rootfs/ingress-controller/indent.sh

@@ -0,0 +1,22 @@
+#!/usr/bin/awk -f
+
+# Copyright 2017 The Kubernetes Authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Credits to https://evasive.ru/f29bd7ebacf24a50c582f973a55eee28.html
+
+{sub(/^[ \t]+/,"");idx=0}
+/\{/{ctx++;idx=1}
+/\}/{ctx--}
+{id="";for(i=idx;i<ctx;i++)id=sprintf("%s%s", id, "\t");printf "%s%s\n", id, $0}