feat(nginx-core): add CORS configs (#79)

nginx-core/Dockerfile

@@ -22,7 +22,12 @@ ENV NGINX_ACCESS_LOG="/var/log/nginx/access.log json" \
     NGINX_FORCE_REDIRECT_STATUS=307 \
     NGINX_AUTO_WEBP="" \
     NGINX_ENTRYPOINT_WORKER_PROCESSES_AUTOTUNE=1 \
-    NGINX_ENTRYPOINT_QUIET_LOGS=""
+    NGINX_ENTRYPOINT_QUIET_LOGS="" \
+    NGINX_CORS_ENABLE="" \
+    NGINX_CORS_ORIGIN="*" \
+    NGINX_CORS_METHODS="GET" \
+    NGINX_CORS_HEADERS="*" \
+    NGINX_CORS_MAXAGE=86400
 
 ENV NGINX_CLIENT_MAX_BODY_SIZE=10m \
     NGINX_SENDFILE=on \

nginx-core/etc/nginx/entrypoint.d/93-cors.sh

@@ -0,0 +1,11 @@
+#!/bin/sh
+set -eu
+
+ME=$(basename "$0")
+
+test -n "${NGINX_CORS_ENABLE:-}" && exit 0
+
+echo "$ME: Remove CORS config"
+rm -fv /etc/nginx/conf.d/location.d/70-cors.conf
+
+exit 0

nginx-core/etc/nginx/templates/location.d/70-cors.conf.template

@@ -0,0 +1,16 @@
+add_header 'Access-Control-Allow-Origin' $NGINX_CORS_ORIGIN;
+add_header 'Access-Control-Allow-Methods' $NGINX_CORS_METHODS;
+add_header 'Access-Control-Allow-Headers' $NGINX_CORS_HEADERS;
+add_header 'Access-Control-Max-Age' $NGINX_CORS_MAXAGE;
+
+if ($request_method = 'OPTIONS') {
+  # Handle OPTIONS requests (preflight requests for complex requests)
+  add_header 'Access-Control-Allow-Origin' $NGINX_CORS_ORIGIN;
+  add_header 'Access-Control-Allow-Methods'  $NGINX_CORS_METHODS;
+  add_header 'Access-Control-Allow-Headers' $NGINX_CORS_HEADERS;
+  add_header 'Access-Control-Max-Age' $NGINX_CORS_MAXAGE;
+  add_header 'Content-Type' 'text/plain charset=UTF-8';
+  add_header 'Content-Length' 0;
+
+  return 204;
+}