by Joche Ojeda | May 15, 2024 | C#, dotnet, Linux, Ubuntu, WSL
Hello, dear readers! Today, we’re going to talk about something called the Windows Subsystem for Linux, or WSL for short. Now, don’t worry if you’re not a tech wizard – this guide is meant to be approachable for everyone!
What is WSL?
In simple terms, WSL is a feature in Windows that allows you to use Linux right within your Windows system. Think of it as having a little bit of Linux magic right in your Windows computer!
Why Should I Care?
Well, WSL is like having a Swiss Army knife on your computer. It can make certain tasks easier and faster, and it can even let you use tools that were previously only available on Linux.
Is It Hard to Use?
Not at all! If you’ve ever used the Command Prompt on your Windows computer, then you’re already halfway there. And even if you haven’t, there are plenty of easy-to-follow guides out there to help you get started.
Do I Need to Be a Computer Expert to Use It?
Absolutely not! While WSL is a powerful tool that many developers love to use, it’s also quite user-friendly. With a bit of curiosity and a dash of patience, anyone can start exploring the world of WSL.
As a DotNet developer, you might be wondering why there’s so much buzz around the Windows Subsystem for Linux (WSL). Let’s dive into the reasons why WSL could be a game-changer for you.
- Seamless Integration: WSL provides a full-fledged Linux environment right within your Windows system. This means you can run Linux commands and applications without needing a separate machine or dual-boot setup.
- Development Environment Consistency: With WSL, you can maintain consistency between your development and production environments, especially if your applications are deployed on Linux servers. This can significantly reduce the “it works on my machine” syndrome.
- Access to Linux-Only Tools: Some tools and utilities are only available or work better on Linux. WSL brings these tools to your Windows desktop, expanding your toolkit without additional overhead.
- Improved Performance: WSL 2, the latest version, runs a real Linux kernel inside a lightweight virtual machine (VM), which leads to faster file system performance and complete system call compatibility.
- Docker Support: WSL 2 provides full Docker support without requiring additional layers for translation between Windows and Linux, resulting in a more efficient and seamless Docker experience.
In conclusion, WSL is not just a fancy tool; it’s a powerful ally that can enhance your productivity and capabilities as a DotNet developer.
by Joche Ojeda | May 14, 2024 | C#, Data Synchronization, dotnet
Hello there! Today, we’re going to delve into the fascinating world of design patterns. Don’t worry if you’re not a tech whiz – we’ll keep things simple and relatable. We’ll use the SyncFramework as an example, but our main focus will be on the design patterns themselves. So, let’s get started!
What are Design Patterns?
Design patterns are like blueprints – they provide solutions to common problems that occur in software design. They’re not ready-made code that you can directly insert into your program. Instead, they’re guidelines you can follow to solve a particular problem in a specific context.
SOLID Design Principles
One of the most popular sets of design principles is SOLID. It’s an acronym that stands for five principles that help make software designs more understandable, flexible, and maintainable. Let’s break it down:
- Single Responsibility Principle: A class should have only one reason to change. In other words, it should have only one job.
- Open-Closed Principle: Software entities should be open for extension but closed for modification. This means we should be able to add new features or functionality without changing the existing code.
- Liskov Substitution Principle: Subtypes must be substitutable for their base types. This principle is about creating new derived classes that can replace the functionality of the base class without breaking the application.
- Interface Segregation Principle: Clients should not be forced to depend on interfaces they do not use. This principle is about reducing the side effects and frequency of required changes by splitting the software into multiple, independent parts.
- Dependency Inversion Principle: High-level modules should not depend on low-level modules. Both should depend on abstractions. This principle allows for decoupling.
Applying SOLID Principles in SyncFramework
The SyncFramework is a great example of how these principles can be applied. Here’s how:
- Single Responsibility Principle: Each component of the SyncFramework has a specific role. For instance, one component is responsible for tracking changes, while another handles conflict resolution.
- Open-Closed Principle: The SyncFramework is designed to be extensible. You can add new data sources or change the way data is synchronized without modifying the core framework.
- Liskov Substitution Principle: The SyncFramework uses base classes and interfaces that allow for substitutable components. This means you can replace or modify components without affecting the overall functionality.
- Interface Segregation Principle: The SyncFramework provides a range of interfaces, allowing you to choose the ones you need and ignore the ones you don’t.
- Dependency Inversion Principle: The SyncFramework depends on abstractions, not on concrete classes. This makes it more flexible and adaptable to changes.
And that’s a wrap for today! But don’t worry, this is just the beginning. In the upcoming series of articles, we’ll dive deeper into each of these principles. We’ll explore how they’re applied in the source code of the SyncFramework, providing real-world examples to help you understand these concepts better. So, stay tuned for more exciting insights into the world of design patterns! See you in the next article!
Related articles
If you want to learn more about data synchronization you can checkout the following blog posts:
- Data synchronization in a few words – https://www.jocheojeda.com/2021/10/10/data-synchronization-in-a-few-words/
- Parts of a Synchronization Framework – https://www.jocheojeda.com/2021/10/10/parts-of-a-synchronization-framework/
- Let’s write a Synchronization Framework in C# – https://www.jocheojeda.com/2021/10/11/lets-write-a-synchronization-framework-in-c/
- Synchronization Framework Base Classes – https://www.jocheojeda.com/2021/10/12/synchronization-framework-base-classes/
- Planning the first implementation – https://www.jocheojeda.com/2021/10/12/planning-the-first-implementation/
- Testing the first implementation – https://youtu.be/l2-yPlExSrg
- Adding network support – https://www.jocheojeda.com/2021/10/17/syncframework-adding-network-support/
by Joche Ojeda | Apr 24, 2024 | C#, netframework
A Beginner’s Guide to System.Security.SecurityRules and SecuritySafeCritical in C#
Introduction
In the .NET Framework, security is a critical concern. Two attributes, System.Security.SecurityRules and SecuritySafeCritical, play a significant role in enforcing Code Access Security (CAS).
System.Security.SecurityRules
The System.Security.SecurityRules attribute specifies the set of security rules that the common language runtime should enforce for an assembly. It has two levels: Level1 and Level2.
Level1
Level1 uses the .NET Framework version 2.0 transparency rules. Here are the key rules for Level1:
- Public security-critical types and members are treated as security-safe-critical outside the assembly.
- Security-critical types and members must perform a link demand for full trust to enforce security-critical behavior when they are accessed by external callers.
- Level1 rules should be used only for compatibility, such as for .NET Framework 2.0 assemblies.
[assembly: System.Security.SecurityRules(System.Security.SecurityRuleSet.Level1)]
public class MyClass
{
// Your code here
}
SecuritySafeCritical
The SecuritySafeCritical attribute identifies types or members as security-critical and safely accessible by transparent code. Code marked with SecuritySafeCritical must undergo a rigorous security audit to ensure that it can be used safely in a secure execution environment. It must validate the permissions of callers to determine whether they have authority to access protected resources used by the code.
[System.Security.SecuritySafeCritical]
public void MyMethod()
{
// Your code here
}
Relationship between System.Security.SecurityRules and SecuritySafeCritical
The System.Security.SecurityRules and SecuritySafeCritical attributes work together to enforce security in .NET Framework. An assembly marked with SecurityRules(SecurityRuleSet.Level1) uses the .NET Framework version 2.0 transparency rules, where public security-critical types and members are treated as security-safe-critical outside the assembly.
The concept of trusted Code
Trusted code refers to code that has been granted certain permissions and is considered safe to execute. It’s a combination of techniques, policies, and procedures for which there is no plausible scenario in which a document retrieved from or reproduced by the system could differ substantially from the document that is originally stored. In other words, trusted code certifies that electronically stored information (ESI) is an authentic copy of the original document or information.
Use Cases and Examples
Consider a scenario where you have a method that performs a critical operation, such as accessing a protected resource. You want to ensure that this method can only be called by trusted code. You can mark this method as SecuritySafeCritical to enforce this.
[System.Security.SecuritySafeCritical]
public void AccessProtectedResource()
{
// Code to access protected resource
}
In this case, the AccessProtectedResource method can only be called by code that has been granted the necessary permissions. This helps to prevent unauthorized access to the protected resource.
Conclusion
Understanding the System.Security.SecurityRules and SecuritySafeCritical attributes is crucial when developing secure .NET applications. By using these attributes correctly, you can enforce robust security rules and protect your application from potential threats. Always remember, with great power comes great responsibility!
I hope this article helps you understand these concepts better. Happy coding! ?
by Joche Ojeda | Apr 23, 2024 | C#, Uncategorized
Castle.Core: A Favourite Among C# Developers
Castle.Core, a component of the Castle Project, is an open-source project that provides common abstractions, including logging services. It has garnered popularity in the .NET community, boasting over 88 million downloads.
Dynamic Proxies: Acting as Stand-Ins
In the realm of programming, a dynamic proxy is a stand-in or surrogate for another object, controlling access to it. This proxy object can introduce additional behaviours such as logging, caching, or thread-safety before delegating the call to the original object.
The Impact of Dynamic Proxies
Dynamic proxies are instrumental in intercepting method calls and implementing aspect-oriented programming. This aids in managing cross-cutting concerns like logging and transaction management.
Castle DynamicProxy: Generating Proxies at Runtime
Castle DynamicProxy, a feature of Castle.Core, is a library that generates lightweight .NET proxies dynamically at runtime. It enables operations to be performed before and/or after the method execution on the actual object, without altering the class code.
Dynamic Proxies in the Realm of ORM Libraries
Dynamic proxies find significant application in Object-Relational Mapping (ORM) Libraries. ORM allows you to interact with your database, such as SQL Server, Oracle, or MySQL, in an object-oriented manner. Dynamic proxies are employed in ORM libraries to create lightweight objects that mirror database records, facilitating efficient data manipulation and retrieval.
Here’s a simple example of how to create a dynamic proxy using Castle.Core:
using Castle.DynamicProxy;
public class SimpleInterceptor : IInterceptor
{
public void Intercept(IInvocation invocation)
{
Console.WriteLine("Before target call");
try
{
invocation.Proceed(); //Calls the decorated instance.
}
catch (Exception)
{
Console.WriteLine("Target threw an exception!");
throw;
}
finally
{
Console.WriteLine("After target call");
}
}
}
public class SomeClass
{
public virtual void SomeMethod()
{
Console.WriteLine("SomeMethod in SomeClass called");
}
}
public class Program
{
public static void Main()
{
ProxyGenerator generator = new ProxyGenerator();
SimpleInterceptor interceptor = new SimpleInterceptor();
SomeClass proxy = generator.CreateClassProxy(interceptor);
proxy.SomeMethod();
}
}
Conclusion
Castle.Core and its DynamicProxy feature are invaluable tools for C# programmers, enabling efficient handling of cross-cutting concerns through the creation of dynamic proxies. With over 825.5 million downloads, Castle.Core’s widespread use in the .NET community underscores its utility. Whether you’re a novice or an experienced C# programmer, understanding and utilizing dynamic proxies, particularly in ORM libraries, can significantly boost your programming skills. Dive into Castle.Core and dynamic proxies in your C# projects and take your programming skills to the next level. Happy coding!
by Joche Ojeda | Apr 20, 2024 | C#
Finding Out the Invoking Methods in .NET
In .NET, it’s possible to find out the methods that are invoking a specific method. This can be particularly useful when you don’t have the source code available. One way to achieve this is by throwing an exception and examining the call stack. Here’s how you can do it:
Throwing an Exception
First, within the method of interest, you need to throw an exception. Here’s an example:
public void MethodOfInterest()
{
throw new Exception("MethodOfInterest was called");
}
Catching the Exception
Next, you need to catch the exception in a higher level method that calls the method of interest:
public void InvokingMethod()
{
try
{
MethodOfInterest();
}
catch (Exception ex)
{
Console.WriteLine(ex.StackTrace);
}
}
In the catch block, we print the stack trace of the exception to the console. The stack trace is a string that represents a stack of method calls that leads to the location where the exception was thrown.
Examining the Call Stack
The call stack is a list of all the methods that were in the process of execution at the time the exception was thrown. By examining the call stack, you can see which methods were invoking the method of interest.
Here’s an example of what a call stack might look like:
at Namespace.MethodOfInterest() in C:\Path\To\File.cs:line 10
at Namespace.InvokingMethod() in C:\Path\To\File.cs:line 20
In this example, InvokingMethod was the method that invoked MethodOfInterest.
Conclusion
By throwing an exception and examining the call stack, you can find out which methods are invoking a specific method in .NET. This can be a useful debugging tool, especially when you don’t have the source code available.
by Joche Ojeda | Mar 7, 2024 | C#, dotnet, netcore, netframework
Understanding AppDomains in .NET Framework and .NET 5 to 8
AppDomains, or Application Domains, have been a fundamental part of isolation and security in the .NET Framework, allowing multiple applications to run under a single process without affecting each other. However, the introduction of .NET Core and its evolution through .NET 5 to 8 has brought significant changes to how isolation and application boundaries are handled. This article will explore the concept of AppDomains in the .NET Framework, their transition and replacement in .NET 5 to 8, and provide code examples to illustrate these differences.
AppDomains in .NET Framework
In the .NET Framework, AppDomains served as an isolation boundary for applications, providing a secure and stable environment for code execution. They enabled developers to load and unload assemblies without affecting the entire application, facilitating application updates, and minimizing downtime.
Creating an AppDomain
using System;
namespace NetFrameworkAppDomains
{
class Program
{
static void Main(string[] args)
{
// Create a new application domain
AppDomain newDomain = AppDomain.CreateDomain("NewAppDomain");
// Load an assembly into the application domain
newDomain.ExecuteAssembly("MyAssembly.exe");
// Unload the application domain
AppDomain.Unload(newDomain);
}
}
}
AppDomains in .NET 5 to 8
With the shift to .NET Core and its successors, the concept of AppDomains was deprecated, reflecting the platform’s move towards cross-platform compatibility and microservices architecture. Instead of AppDomains, .NET 5 to 8 emphasizes on assembly loading contexts for isolation and the use of containers (like Docker) for application separation.
AssemblyLoadContext in .NET 5 to 8
using System;
using System.Reflection;
using System.Runtime.Loader;
namespace NetCoreAssemblyLoading
{
class Program
{
static void Main(string[] args)
{
// Create a new AssemblyLoadContext
var loadContext = new AssemblyLoadContext("MyLoadContext", true);
// Load an assembly into the context
Assembly assembly = loadContext.LoadFromAssemblyPath("MyAssembly.dll");
// Execute a method from the assembly (example method)
MethodInfo methodInfo = assembly.GetType("MyNamespace.MyClass").GetMethod("MyMethod");
methodInfo.Invoke(null, null);
// Unload the AssemblyLoadContext
loadContext.Unload();
}
}
}
Differences and Considerations
- Isolation Level: AppDomains provided process-level isolation without needing multiple processes. In contrast,
AssemblyLoadContext provides a lighter-weight mechanism for loading assemblies but doesn’t offer the same isolation level. For higher isolation, .NET 5 to 8 applications are encouraged to use containers or separate processes.
- Compatibility: AppDomains are specific to the .NET Framework and are not supported in .NET Core and its successors. Applications migrating to .NET 5 to 8 need to adapt their architecture to use
AssemblyLoadContext or explore alternative isolation mechanisms like containers.
- Performance: The move away from AppDomains to more granular assembly loading and containers reflects a shift towards microservices and cloud-native applications, where performance, scalability, and cross-platform compatibility are prioritized.
Conclusion
While the transition from AppDomains to AssemblyLoadContext and container-based isolation marks a significant shift in application architecture, it aligns with the modern development practices and requirements of .NET applications. Understanding these differences is crucial for developers migrating from the .NET Framework to .NET 5 to
