Issue-#852: Add 2 registry services, nginx conf

content/tutorials/compute-to-data-docker-registry.md

@@ -1,6 +1,6 @@
 ---
 title: Setting up private docker registry for Compute-to-Data environment
-description: Learn how to setup own docker registry and push images for running algorithms in C2D environment.
+description: Learn how to setup your own docker registry and push images for running algorithms in a C2D environment.
 ---
 
 ## Prerequisites
@@ -9,6 +9,14 @@ description: Learn how to setup own docker registry and push images for running
 2. Domain name is mapped to the server IP address.
 3. SSL certificate
 
+## Generate certificates
+
+```bash
+# install certbot: https://certbot.eff.org/
+sudo certbot certonly --standalone --cert-name example.com -d example.com
+sudo certbot certonly --standalone --cert-name admin.example.com -d admin.example.com
+```
+
 ## Generate password file
 
 Replace content in `<>` with appropriate content.
@@ -22,6 +30,7 @@ docker run \
 ## Docker compose template file for registry
 
 Copy the below yml content to `docker-compose.yml` file and replace content in `<>`.
+Here, we will be creating two services of the docker registry so that anyone can `pull` the images from the registry but, only authenticated users can `push` the images.
 
 ```yml
 version: '3'
@@ -34,8 +43,6 @@ services:
     ports:
       - 5050:5000
     environment:
-      REGISTRY_HTTP_TLS_CERTIFICATE: /certs/domain.crt
-      REGISTRY_HTTP_TLS_KEY: /certs/domain.key
       REGISTRY_AUTH: htpasswd
       REGISTRY_AUTH_HTPASSWD_PATH: /auth/htpasswd
       REGISTRY_AUTH_HTPASSWD_REALM: Registry Realm
@@ -43,7 +50,74 @@ services:
     volumes:
       - <path>/data:/var/lib/registry
       - <path>/auth:/auth
-      - <path>/certs:/certs
+  registry-read-only:
+      restart: always
+      container_name: my-registry-read-only
+      image: registry:2
+      read_only: true
+      ports:
+        - 5051:5000
+      environment:
+        REGISTRY_HTTP_SECRET: ${REGISTRY_HTTP_SECRET}
+      volumes:
+        - <path>/docker-registry/data:/var/lib/registry:ro
+      depends_on:
+        - registry
+  nginx:
+        image: nginx:latest
+        container_name: nginx
+        volumes:
+            -  <path>/nginx/logs:/app/logs/
+            -  nginx.conf:/etc/nginx/nginx.conf
+            -  /etc/letsencrypt/:/etc/letsencrypt/
+        ports:
+            - 80:80
+            - 443:443
+        depends_on:
+            - registry-read-only
+```
+
+## Nginx configuration
+
+```
+events {}
+http {
+  access_log /app/logs/access.log;
+  error_log /app/logs/error.log;
+	
+	server {
+        client_max_body_size 4096M;
+    		listen 80 default_server;
+    		server_name _;
+    		return 301 https://$host$request_uri;
+	}
+
+  server {
+           # Allowed request size should be large enough to allow push operations
+           client_max_body_size 4096M;
+           listen 443 ssl;
+           server_name admin.example.com;
+           ssl_certificate /etc/letsencrypt/live/admin.example.com/fullchain.pem;
+           ssl_certificate_key /etc/letsencrypt/live/admin.example.com/privkey.pem;
+           location / {
+                   proxy_connect_timeout 75s;
+                   proxy_pass http://registry:5000;
+           }
+  }
+
+  server {
+          # Allowed request size should be large enough to allow pull operations
+          client_max_body_size 4096M;
+          listen 443 ssl;
+          server_name example.com;
+          ssl_certificate /etc/letsencrypt/live/example.com/fullchain.pem;
+          ssl_certificate_key /etc/letsencrypt/live/example.com/privkey.pem;
+          location / {
+                  proxy_connect_timeout 75s;
+                  proxy_pass http://registry-read-only:5000;
+          }
+  }
+}
 
 ```
 
@@ -61,16 +135,15 @@ curl -X GET -u <username>:<password> https://example.com/v2/_catalog
 
 ## Other useful commands
 
-
-## Login to registry
+### Login to registry
 
 ```bash
 docker login example.com -u <username> -p <password>
 ```
 
-## Build and push image to registry
+### Build and push an image to the registry
 
-Use the commands below to build an image from a  `Dockerfile` and push to your own private registry.
+Use the commands below to build an image from a  `Dockerfile` and push it to your private registry.
 
 ```bash
 docker build . -t example.com/my-algo:latest
@@ -80,4 +153,4 @@ docker image tag example.com/my-algo:latest
 
 ## Next step
 
-You can publish an algorithm asset with the metadata containing registry url, image, and tag information to enable users to run C2D jobs. 
+You can publish an algorithm asset with the metadata containing registry URL, image, and tag information to enable users to run C2D jobs.