docs: extend README on usage of docker image

Author: LexLuengas

README.md

@@ -29,23 +29,20 @@ supported.
 ## Installation
 
 To install the CLI globally:
+
 ```npm install -g openapi-cop```
 
-To install the package locally (inside an existing NPM package) and run the proxy programatically:  
-```npm install openapi-cop```
+To install the package locally (inside an existing NPM package) and run the proxy programatically:
 
-We also publish a Docker image [lxlu/openapi-cop](https://hub.docker.com/r/lxlu/openapi-cop) that you can use for your
-convenience. This means you can also run openapi-cop with
-something like
-```docker run --rm -p 8888:8888 lxlu/openapi-cop```
+```npm install openapi-cop```
 
 ## Usage
 
 There are three ways to run openapi-cop:
 
-1. Start it with the CLI.
-2. Run it programatically inside Node.js.
-3. Start a container based on the Docker image.
+1. Start it with the CLI ([1](#cli-usage)).
+2. Run it programatically inside Node.js ([2](#module-usage)).
+3. Start a container based on the Docker image ([3](#docker-image-usage)).
 
 ### CLI Usage
 
@@ -228,6 +225,16 @@ const server = await runProxy({
 });
 ```
 
+### Docker Image Usage
+
+We publish a Docker image [lxlu/openapi-cop](https://hub.docker.com/r/lxlu/openapi-cop) that you can use for your
+convenience. This means you can also run openapi-cop with
+something like
+
+```docker run --rm -p 8888:8888 --env TARGET=https://some-host-name:1234 --env FILE=some-openapi-document.json lxlu/openapi-cop```
+
+Read more information about the usage [here](./docker/README.md).
+
 ## FAQ
 
 <details>

docker/README.md

@@ -34,6 +34,13 @@ same [openapi-cop CLI flags](https://github.com/EXXETA/openapi-cop#cli-usage):
 - `VERBOSE`: When set, activates verbose output.
 - `NODE_ENV` (default: "production"): When set to "development", stack traces will also be logged.
 
+### Example
+
+The following command will run the proxy against a provided target server, taking as a reference a given OpenAPI
+document, and expose port 8888 to the host system.
+
+```docker run --rm -p 8888:8888 --env TARGET=https://some-host-name:1234 --env FILE=some-openapi-document.json lxlu/openapi-cop```
+
 ## License
 
 See https://github.com/EXXETA/openapi-cop/blob/master/LICENSE.