Roslyn analyzers inspect your code for style, quality, maintainability, design and other issues. Because they are powered by the .NET Compiler Platform, they can produce warnings in your code as you type even before you’ve finished the line. In other words, you don’t have to build your code to find out that you made a mistake. Analyzers can also surface an automatic code fix through the Visual Studio light bulb prompt that allows you to clean up your code immediately. 

gRPC Service with .NET 7
In this video we build a gRPC service with 5 methods: Create, Read (single), List (multiple), Update and Delete. We then employ JSON transcoding (a new feature added in .NET 7) to allow our gRPC service to act as a REST based API. This allows web-based endpoints to consume our service, while at the same time continuing to allow native gRPC clients to consume as well.


⏲️ Time Codes ⏲️

- 0:33 - Welcome
- 2:00 - gRPC Overview
- 5:08 - Scaffold the prject
- 9:58 - Test "greeter" service with Postman
- 12:32 - Add package dependencies
- 14:48 - Create the Model
- 16:38 - Create DB Context & migrations
- 22:37 - Define the protobuf file
- 32:39 - Build the first service method
- 40:55 - Test method with postman
- 42:52 - Read method
- 48:42 - List method
- 52:39 - Update method
- 59:14 - Delete method
- 1:03:24 - Add the annotation files
- 1:06:07 - Annotate the first gRPC method
- 1:09:26 - Annotate remaining methods
- 1:12:42 - Test with Postman
- 1:16;00 - Patreon supporter credits 

.NET 8 RC1 is now available. This is our first of two release candidates. This release includes a new AOT mode for both Android and WASM, System.Text.Json improvements, and Azure Managed Identity support for containers. Now is great time to pick up and test .NET 8 if you haven’t yet.  

A common question from customers is how to have an RPC (as in .NET Remoting and Windows Communication Foundation) experience on .NET Core. We are contributing to the gRPC (grpc.io) project to ensure gRPC will have first-class support for .NET developers. 

/* 
 * Password Hashing With PBKDF2 (http://crackstation.net/hashing-security.htm).
 * Copyright (c) 2013, Taylor Hornby
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without 
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice, 
 * this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation 
 * and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE 
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 
 * POSSIBILITY OF SUCH DAMAGE.
 */

using System;
using System.Text;
using System.Security.Cryptography;

namespace PasswordHash
{
    /// <summary>
    /// Salted password hashing with PBKDF2-SHA1.
    /// Author: havoc AT defuse.ca
    /// www: http://crackstation.net/hashing-security.htm
    /// Compatibility: .NET 3.0 and later.
    /// </summary>
    public class PasswordHash
    {
        // The following constants may be changed without breaking existing hashes.
        public const int SALT_BYTE_SIZE = 24;
        public const int HASH_BYTE_SIZE = 24;
        public const int PBKDF2_ITERATIONS = 1000;

        public const int ITERATION_INDEX = 0;
        public const int SALT_INDEX = 1;
        public const int PBKDF2_INDEX = 2;

        /// <summary>
        /// Creates a salted PBKDF2 hash of the password.
        /// </summary>
        /// <param name="password">The password to hash.</param>
        /// <returns>The hash of the password.</returns>
        public static string CreateHash(string password)
        {
            // Generate a random salt
            RNGCryptoServiceProvider csprng = new RNGCryptoServiceProvider();
            byte[] salt = new byte[SALT_BYTE_SIZE];
            csprng.GetBytes(salt);

            // Hash the password and encode the parameters
            byte[] hash = PBKDF2(password, salt, PBKDF2_ITERATIONS, HASH_BYTE_SIZE);
            return PBKDF2_ITERATIONS + ":" +
                Convert.ToBase64String(salt) + ":" +
                Convert.ToBase64String(hash);
        }

        /// <summary>
        /// Validates a password given a hash of the correct one.
        /// </summary>
        /// <param name="password">The password to check.</param>
        /// <param name="correctHash">A hash of the correct password.</param>
        /// <returns>True if the password is correct. False otherwise.</returns>
        public static bool ValidatePassword(string password, string correctHash)
        {
            // Extract the parameters from the hash
            char[] delimiter = { ':' };
            string[] split = correctHash.Split(delimiter);
            int iterations = Int32.Parse(split[ITERATION_INDEX]);
            byte[] salt = Convert.FromBase64String(split[SALT_INDEX]);
            byte[] hash = Convert.FromBase64String(split[PBKDF2_INDEX]);

            byte[] testHash = PBKDF2(password, salt, iterations, hash.Length);
            return SlowEquals(hash, testHash);
        }

        /// <summary>
        /// Compares two byte arrays in length-constant time. This comparison
        /// method is used so that password hashes cannot be extracted from
        /// on-line systems using a timing attack and then attacked off-line.
        /// </summary>
        /// <param name="a">The first byte array.</param>
        /// <param name="b">The second byte array.</param>
        /// <returns>True if both byte arrays are equal. False otherwise.</returns>
        private static bool SlowEquals(byte[] a, byte[] b)
        {
            uint diff = (uint)a.Length ^ (uint)b.Length;
            for (int i = 0; i < a.Length && i < b.Length; i++)
                diff |= (uint)(a[i] ^ b[i]);
            return diff == 0;
        }

        /// <summary>
        /// Computes the PBKDF2-SHA1 hash of a password.
        /// </summary>
        /// <param name="password">The password to hash.</param>
        /// <param name="salt">The salt.</param>
        /// <param name="iterations">The PBKDF2 iteration count.</param>
        /// <param name="outputBytes">The length of the hash to generate, in bytes.</param>
        /// <returns>A hash of the password.</returns>
        private static byte[] PBKDF2(string password, byte[] salt, int iterations, int outputBytes)
        {
            Rfc2898DeriveBytes pbkdf2 = new Rfc2898DeriveBytes(password, salt);
            pbkdf2.IterationCount = iterations;
            return pbkdf2.GetBytes(outputBytes);
        }
    }
}

EF Core 8, or just EF8, is the successor to EF Core 7. EF8 requires .NET 8. It will not work with .NET 6 or 7, or with any version of .NET Framework. 

In this post, we introduced the idea that not all performance optimisations need to be complex to implement. In this example, we optimised the ToUrl method of the NEST library by conditionally avoiding executing code we know would cause allocations.