Check in a simple docker-compose to run the app behind an nginx proxy

So that we can test the reverse proxy configuration fixes in dev

This fixes #24 (comment)

The `docker-compose` (except for `nginx`) should be kept consistent with the
production `docker-compose-prod.yml` with the exception of `DASH_DEBUG_MODE`,
which is set to true so that we can debug errors in the setup more easily

Testing done:
- Built and ran the docker-compose
- Accessing http://localhost:8060/admin gives the same error as
#24 (comment)

```
Uncaught ReferenceError: DashRenderer is not defined
    <anonymous> http://localhost:8060/admin/:58
```

README.md

@@ -68,6 +68,13 @@ To learn more about Dash, please visit [documentation](https://plot.ly/dash).
 
 `docker compose -f docker-compose-dash-app.yml up`
 
+## Test with a reverse proxy
+
+```
+docker-compose -f docker-compose-prod-nginx.yml build
+docker-compose -f docker-compose-prod-nginx.yml up -d
+```
+
 # Dynamic Config
 
 ## Set Variables

docker-compose-prod-nginx.yml

@@ -0,0 +1,51 @@
+# docker-compose-prod-ngnix.yml
+# used for testing with the ngnix reverse proxy
+version: "3"
+services:
+  dashboard:
+    build:
+      context: .
+      dockerfile: docker/Dockerfile
+    image: e-mission/opdash:0.0.1
+    environment:
+      DASH_DEBUG_MODE: "True"
+      DASH_SERVER_PORT: 8050
+      DB_HOST: db
+      WEB_SERVER_HOST: 0.0.0.0
+      SERVER_BRANCH: master
+      CONFIG_PATH: "https://raw.githubusercontent.com/e-mission/nrel-openpath-deploy-configs/main/configs/"
+      STUDY_NAME: "stage-program"
+      AUTH_TYPE: "basic" # the other option is cognito
+      DASH_REQUESTS_PATHNAME_PREFIX: "/"
+    networks:
+       - emission
+    deploy:
+      restart_policy:
+          condition: on-failure
+    depends_on:
+      - db
+      - nginxrp
+  db:
+    image: mongo:4.4.0
+    deploy:
+      replicas: 1
+      restart_policy:
+        condition: on-failure
+    networks:
+       - emission
+  nginxrp:
+    image: nginx:1.24.0
+    deploy:
+      replicas: 1
+      restart_policy:
+        condition: on-failure
+    networks:
+       - emission
+    volumes:
+      - ./docker/ngnix.conf:/etc/nginx/nginx.conf:ro
+    ports:
+      - "8060:80"
+
+
+networks:
+  emission:

docker/ngnix.conf

@@ -0,0 +1,46 @@
+events { }
+http {
+    server {
+        listen 80;
+        charset utf-8;
+        server_tokens off;
+
+# Re-enable once we have figured out how to get the set_headers module to work        
+#         more_set_headers "X-XSS-Protection: 1; mode=block";
+#         more_set_headers "Access-Control-Allow-Origin: $host";
+#         more_set_headers "X-Frame-Options: SAMEORIGIN";
+#         more_set_headers "Referrer-Policy: same-origin";
+#         more_set_headers "Allow: GET, POST, HEAD";
+        if ($request_method ~ ^(OPTIONS)$ ) { return 403; }
+
+#         proxy_cookie_path off;
+#         proxy_cookie_path / "/; HTTPOnly; Secure";
+
+        error_page 404 https://www.nrel.gov/notfound;
+
+        location /static {
+            alias /www/static;
+        }
+
+        location / {
+            rewrite /(.+$) /api/$1 break;
+        }
+
+        location /admin/ {
+            proxy_pass http://dashboard:8050/;
+            proxy_pass_header Content-Type;
+            proxy_set_header X-Real-IP $remote_addr;
+            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+            proxy_hide_header Access-Control-Allow-Origin;
+            proxy_http_version 1.1;
+            proxy_set_header Upgrade $http_upgrade;
+            proxy_set_header Connection "upgrade";
+            proxy_set_header Host $host;
+            proxy_cookie_path / "/; Secure; HttpOnly; SameSite=strict";
+            client_max_body_size 1G;
+            proxy_read_timeout 300;
+            proxy_connect_timeout 300;
+            proxy_send_timeout 300;
+        }
+    }
+}