Route forwarding server proxy

[fmazmz]

Whats new?

• ProxyRoute.java holds a mapping of a basePath and its respective target upstream URL.
  The mappings are added in application-properties.yml and loaded through the ConfigLoader, stored as ProxyRoute objects.

• ProxyPlugin.java, for each ProxyRoute object, we initialize a new ProxyPlugin.
  The plugin handles the following:
  -Logs the incoming request from the client.
  -Constructs a new HttpRequest and copies the headers, body, and method from the initial Client request.
  -Proxies the new request through an HttpClient to the target server URL.
  -Handles and returns the upstream server response and returns it back to the client.

• HttpStatus.java (ENUM) holds the most common Http Status Codes and their respective String description. Allows us to easily translate the statusCode from the upstream server response and dynamically relay an http status text to the client.

• Integration tests and Unit tests added for ProxyPlugin to test most basic scenarios, both with a real HttpClient and a mock.

• One proxy route added to the server config as following:

server:
  port: 8080
  root-dir: static
  proxy:
    routes:
      - base-route: /api/test
        upstream-url: https://jsonplaceholder.typicode.com

How to run an example request to test the proxy?

• Run the application locally
• Visit localhost:8080/api/test/{route} - with any of the routes documented below or at https://jsonplaceholder.typicode.com/

The request should be proxied to the external server.

Resources

JSONPlaceholder comes with a set of 6 common resources:

/posts	100 posts
/comments	500 comments
/albums	100 albums
/photos	5000 photos
/todos	200 todos
/users	10 users

closes #111
@coderabbitai ignore

[kristinaxm]

Well done!