Design patterns are reusable solutions to common software problems that can improve the quality, maintainability, and scalability of your code. But how do you apply design patterns to secure privacy, especially when working with sensitive data or user information? In this article, you will learn about some design patterns that can help you protect privacy in your software projects, such as:
This pattern involves encrypting data before storing or transmitting it, so that only authorized parties can access it. Encryption can be applied at different levels, such as the database, the application, or the network. You can use various encryption algorithms and techniques, such as symmetric, asymmetric, or hybrid encryption, depending on your security and performance requirements. Encryption can help you prevent data breaches, comply with regulations, and build trust with your users.
Popular examples include - s3 client side encryption with KMS-manged customer master key - password encryption - encryption of data at rest and transit
I would add a hardware and transport encryption layers here since it's often missed because it's just a common part of our life. E.g smartphone personal data encryption which is an integral part of every device today and https protocol widely used across the internet. These are not required to apply much effort to use and definitely makes our life safer and protected from the unwanted eyes.
This pattern involves creating a proxy object that acts as an intermediary between the client and the real object. The proxy can control the access to the real object, perform additional operations, or hide some details from the client. For example, you can use a proxy to filter out sensitive data from the response, apply authentication or authorization rules, or log the requests and responses. Proxy can help you enhance security, reduce coupling, and simplify the interface of the real object.
interface IInternetAccess { public ConnectToInternet(string hostName); } class RawInternetAccess:IInternetAccess { public ConnectToInternet(string hostName) { //Code to Connect to Internet } } class ProxyInternetAccess:IInternetAccess { List<string> bannedHostNames = {"site1", "site2", "site3"}; IInternetAccess objInternetAccess = new RawInternetAccess(); public ConnectToInternet(string hostName) { if(!bannedHostNames.Contains(hostName) objInternetAccess .ConnectToInternet(hostName); else Alert("Banned"); } }
Proxy object can also include a load balancer functionality which means it can hide multiple objects with the identical functionality. The difference from the facade would be adding the scalability feature without reducing or rearranging the functionality of the original objects. In terms of privacy that means the real power or setup of the system is hidden and may provide extra benefits like performance without revealing the implementation details.
This pattern involves creating a facade object that provides a simplified and unified interface to a complex system or subsystem. The facade can abstract away the complexity and details of the system, and expose only the relevant functionality to the client. For example, you can use a facade to wrap multiple services or components that handle data processing, validation, or encryption, and provide a single method to access them. Facade can help you reduce complexity, improve readability, and increase modularity.
Personally found this one useful together with the chain-of-responsibility which allows to put reduce the possible heaviness in logic of the facade itself. The examples may be Node.JS middleware and promise chains.
I certainly agree with the use of Facade design pattern. As rightly said the facade can abstract away the complexity and details of the system, and expose only the relevant functionality to the client.Facade certainly help you reduce complexity, improve readability and increase modulatory.
This pattern involves creating a subject object that maintains a list of observers, and notifying them of any changes in its state. The observers can register or unregister themselves from the subject, and react to the notifications according to their own logic. For example, you can use an observer to implement a privacy policy manager that notifies the users of any changes in the policy, and allows them to accept or reject them. Observer can help you implement event-driven communication, decouple the subject and the observers, and support dynamic behavior.
interface IObserver { public void Notify(); } interface IObservable { public void Subscribe(IObserver); } class Subject : IObservable { List<IObserver> policyHandlers = new(); public void Subscribe(IObserver observer) { policyHandlers.Add(observer); } public void Action() { //On Policy Change foreach(IObserver observer in errHandlers) observer.Notify(); } } class PolicyHandler1: IObserver { public void Notify() { //Do Some Action; } } class PolicyHandler2:IObserver { public void Notify() { //Do Another Action; } } class main() { IObservable obj = new Subject(); obj.Subscribe(new PolicyHandler1()); obj.Subscribe(new PolicyHandler2()); }
This pattern involves creating a strategy interface that defines a common behavior, and implementing multiple concrete strategies that follow the interface. The client can choose the appropriate strategy at runtime, and pass it to a context object that executes the behavior. For example, you can use a strategy to implement different privacy settings for different user groups, and allow the user to switch between them. Strategy can help you support multiple algorithms, avoid conditional logic, and enable flexibility and extensibility.
These are just some of the design patterns that can help you secure privacy in your software projects. Of course, there are many other design patterns that can also be useful, depending on your specific needs and goals. The key is to understand the problem you are trying to solve, the benefits and drawbacks of each pattern, and how to apply them correctly and consistently.
Design patterns are useful at any level of system, not just coding but also a devops making the whole system more secure, reliable and responsive.