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JavaScript Design Patterns for Coding Interviews

Challenge: Solution Review

Explore the proxy design pattern by reviewing a JavaScript solution that restricts students' access to certain apps and websites through a library kiosk interface. Understand how the proxy controls access, blocks restricted resources, and optimizes requests. This lesson solidifies your grasp of structural patterns for coding interviews.

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Solution #

Node.js
class LibraryKiosk{
    open(app){
        console.log(`Opening ${app}`)
    }    
    connectTo(website) 
    { 
        console.log("Connecting to "+ website); 
    } 
}
class ProxyLibraryKiosk{
    constructor(){
        this.libraryKiosk = new LibraryKiosk() 
        this.blockedSites = ["fb.com", "instagram.com","snapchat.com","google.com", "gmail.com"]
        this.blockedApps = ["camera", "photos", "music", "settings"] 
    }
    
    open(app){
        if(this.blockedApps.includes(app)){
            console.log(`You can't access the ${app}`)
        }else{
            this.libraryKiosk.open(app)
        }
    }
    connectTo(website){
        if(this.blockedSites.includes(website)){
            console.log(`Access to ${website} denied`)
        }else{
            this.libraryKiosk.connectTo(website)
        }
    }
}
var libraryKiosk = new ProxyLibraryKiosk(); 
libraryKiosk.open("photos")
libraryKiosk.open("Chrome")
libraryKiosk.connectTo("booksportal.com"); 
libraryKiosk.connectTo("google.com");

Explanation

In this challenge, you had to implement the proxy pattern, such that it restricted the use of the kiosk to access apps/websites for the students. As mentioned in the problem statement, a student can access/connect to any app/site using the LibraryKiosk class.

class LibraryKiosk{
    open(app){
...