## Proxy Design Pattern

### Ex $1$

Suppose you are working on a project to develop a document management system for a large organization with multiple departments and teams. The system is expected to handle a high volume of document uploads, downloads, and edits, and to provide advanced search and filtering capabilities.

Your task is to create a proxy that can be used by the document management system to provide access to the underlying document storage system. The proxy should perform the following tasks:

$1.$ Control access to the document storage system based on the user's credentials and permissions.

$2.$ Manage user sessions and authenticate users before allowing them to access the system.

$3.$ Filter and transform the document metadata and content to match the user's preferences and display requirements.

$4.$ Monitor user activity and log all document$-$related actions for auditing purposes.

$5.$ Provide advanced search and filtering capabilities to help users find the documents they need.

To complete this exercise, you will need to use the proxy pattern to create a new component that can intercept requests for document storage and provide a secure and easy$-$to$-$use access mechanism for the users. You will also need to use advanced techniques for data management and search indexing to ensure that the proxy can handle the high volume of documents and provide fast access to the relevant information.

In addition, you may need to consider issues such as scalability, fault tolerance, and performance monitoring to ensure that the proxy is robust and can perform well in a production environment. You may also need to consider implementing caching or other optimization techniques to minimize the number of requests made to the document storage system and reduce the load on the network.