fix: DNS name resolving not working in kubernetes (#339)

fixes #339

README.md

@@ -83,6 +83,8 @@ Checkout all options in [Available options](#available-options) section.
     - You should add a CORS Policy on your bucket, check the issue [#193](https://github.com/Joxit/docker-registry-ui/issues/193).
 -   Why my docker registry server is returning an error `pagination number invalid` ?
     - Since docker registry server 2.8.2 there is default limit of 1000 images in catalog. If you need more images update the configuration `REGISTRY_CATALOG_MAXENTRIES` with your max value and check the issue [#306](https://github.com/Joxit/docker-registry-ui/issues/306).
+-   I'm using `NGINX_PROXY_PASS_URL`, my registry server has been recreated and the UI cannot connect with the message `[error] 176#176: *2 connect() failed (111: Connection refused) while connecting to upstream`, what can I do?
+    - Nginx get the IP of all addresses only once at runtime, since your container has been recreated, its IP changed too. To prevent this kind of issue, you may use the option `NGINX_RESOLVER` and set to `127.0.0.11`.
 
 Need more informations ? Try my [examples](https://github.com/Joxit/docker-registry-ui/tree/main/examples) or open an issue.
 
@@ -103,6 +105,7 @@ Some env options are available for use this interface for **only one server** (w
 - `NGINX_PROXY_HEADER_*`: Update the default Nginx configuration and **set custom headers** for your backend docker registry via environment variable and file (`/etc/nginx/.env`). Only when `NGINX_PROXY_PASS_URL` is used (see [#89](https://github.com/Joxit/docker-registry-ui/pull/89)). Since 1.2.3
 - `NGINX_PROXY_PASS_HEADER_*`: Update the default Nginx configuration and **forward custom headers** to your backend docker registry via environment variable and file (`/etc/nginx/.env`). Only when `NGINX_PROXY_PASS_URL` is used (see [#206](https://github.com/Joxit/docker-registry-ui/issues/206)). Since 2.1.0
 - `NGINX_LISTEN_PORT`: Listen on a port other than 80, you can also change the default user and set to nginx `--user nginx` (see [#224](https://github.com/Joxit/docker-registry-ui/issues/224) and [#234](https://github.com/Joxit/docker-registry-ui/pull/234)). (default: `80` when the user is root, `8080` otherwise). Since 2.2.0
+- `NGINX_RESOLVER`: Add [`resolver`](http://nginx.org/en/docs/http/ngx_http_core_module.html#resolver) directive to the nginx configuration for dynamic dns resolving. The value when you are using a docker network is `127.0.0.11`, you can set a custom DNS server too with a valid time. This is not needed when you are using kubernetes. (see [#333](https://github.com/Joxit/docker-registry-ui/issues/333) and [#339](https://github.com/Joxit/docker-registry-ui/issues/339)). (default: ``). Since 2.5.5
 - `DEFAULT_REGISTRIES`: List of comma separated registry URLs (e.g `http://registry.example.com,http://registry:5000`), available only when `SINGLE_REGISTRY=false` (see [#219](https://github.com/Joxit/docker-registry-ui/pull/219)). (default: ` `). Since 2.1.0
 - `READ_ONLY_REGISTRIES`: Deactivate dialog for remove and add new registries, available only when `SINGLE_REGISTRY=false` (see [#219](https://github.com/Joxit/docker-registry-ui/pull/219)). (default: `false`). Since 2.1.0
 - `SHOW_CATALOG_NB_TAGS`: Show number of tags per images on catalog page and hide images with 0 tags. This will produce + nb images requests, **not recommended on large registries** (see [#161](https://github.com/Joxit/docker-registry-ui/issues/161) and [#239](https://github.com/Joxit/docker-registry-ui/pull/239)). (default: `false`). Since 2.2.0

bin/90-docker-registry-ui.sh

@@ -65,7 +65,13 @@ if [ -n "${NGINX_PROXY_PASS_URL}" ] ; then
   sed -i "s,\${NGINX_PROXY_PASS_URL},${NGINX_PROXY_PASS_URL}," /etc/nginx/conf.d/default.conf
   sed -i "s^\${NGINX_PROXY_HEADERS}^$(get_nginx_proxy_headers)^" /etc/nginx/conf.d/default.conf
   sed -i "s^\${NGINX_PROXY_PASS_HEADERS}^$(get_nginx_proxy_pass_headers)^" /etc/nginx/conf.d/default.conf
-  sed -i "s,#!,," /etc/nginx/conf.d/default.conf
+  sed -i "s,#! , ," /etc/nginx/conf.d/default.conf # The space is important here, to not interfer with #!r
+  if [ -n "${NGINX_RESOLVER}" ]; then
+    sed -i "s,\${NGINX_RESOLVER},${NGINX_RESOLVER}," /etc/nginx/conf.d/default.conf
+    sed -i "s,#r,," /etc/nginx/conf.d/default.conf
+  else
+    sed -i "s,#!r, ," /etc/nginx/conf.d/default.conf # The space is for cosmetic here
+  fi
 fi
 
 if [ "$(whoami)" != "root" ]; then

nginx/default.conf

@@ -1,9 +1,9 @@
 server {
     listen       80;
     server_name  localhost;
-#!    resolver 127.0.0.11; # This is for docker container name resolver
-    #charset koi8-r;
-    #access_log  /var/log/nginx/host.access.log  main;
+#r    resolver ${NGINX_RESOLVER}; # This is for docker container name resolver
+    # charset koi8-r;
+    # access_log  /var/log/nginx/host.access.log  main;
 
     # disable any limits to avoid HTTP 413 for large image uploads
     client_max_body_size 0;
@@ -31,23 +31,17 @@ server {
 #!        proxy_http_version 1.1;
 #!        ${NGINX_PROXY_HEADERS}
 #!        ${NGINX_PROXY_PASS_HEADERS}
-#!        set $registry_server "${NGINX_PROXY_PASS_URL}";
-#!        proxy_pass $registry_server;
+#r        set $registry_server "${NGINX_PROXY_PASS_URL}";
+#r        proxy_pass $registry_server;
+#!r       proxy_pass ${NGINX_PROXY_PASS_URL};
 #!    }
 
-    #error_page  404              /404.html;
+    # error_page  404              /404.html;
 
     # redirect server error pages to the static page /50x.html
     #
     error_page   500 502 503 504  /50x.html;
     location = /50x.html {
         root   /usr/share/nginx/html;
     }
-
-    # deny access to .htaccess files, if Apache's document root
-    # concurs with nginx's one
-    #
-    #location ~ /\.ht {
-    #    deny  all;
-    #}
 }

package.json

@@ -1,6 +1,6 @@
 {
   "name": "docker-registry-ui",
-  "version": "2.5.4",
+  "version": "2.5.5",
   "type": "module",
   "scripts": {
     "format": "npm run format-html && npm run format-js && npm run format-riot",