Add v4, with proxy, app and db

bulletin-board-proxy/Dockerfile

@@ -0,0 +1,4 @@
+FROM nginx:1.13.6
+
+RUN mkdir -p /data/nginx/cache
+COPY nginx.conf /etc/nginx/nginx.conf

bulletin-board-proxy/nginx.conf

@@ -0,0 +1,43 @@
+user  nginx;
+worker_processes  1;
+
+error_log  /var/log/nginx/error.log warn;
+pid        /var/run/nginx.pid;
+
+events {
+    worker_connections  1024;
+}
+
+http {
+    proxy_cache_path /data/nginx/cache levels=1:2 keys_zone=STATIC:30m inactive=24h  max_size=200m use_temp_path=off;
+
+    proxy_pass_request_headers  on;
+    proxy_redirect  off;
+    proxy_set_header Host $host;
+    proxy_set_header  Connection keep-alive;
+    
+    gzip  on;
+    gzip_proxied  any;
+
+    add_header 	X-Host $hostname;
+    add_header  X-Cache-Status $upstream_cache_status;
+
+    map $sent_http_content_type $expires {
+        default                    off;
+        ~image/                    6M;
+    }   
+
+    server {
+        listen 80 default_server;
+        server_name _;
+
+        expires $expires;
+
+        location / {
+            proxy_pass http://bb-app:8080/;
+            proxy_cache            STATIC;
+            proxy_cache_valid      200  1h;
+            proxy_cache_use_stale  error timeout invalid_header updating http_500 http_502 http_503 http_504;
+        }
+    }
+}