[release/8.0] Generate and store random RG name when provisioning

src/Aspire.Hosting.Azure/Provisioning/AzureProvisionerOptions.cs

@@ -11,6 +11,11 @@ internal sealed class AzureProvisionerOptions
 
     public string? ResourceGroup { get; set; }
 
+    /// <summary>
+    /// Gets or sets a prefix used in resource groups names created.
+    /// </summary>
+    public string? ResourceGroupPrefix { get; set; }
+
     public bool? AllowResourceGroupCreation { get; set; }
 
     public string? Location { get; set; }

src/Aspire.Hosting.Azure/Provisioning/Provisioners/AzureProvisioner.cs

@@ -2,10 +2,12 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 
 using System.Reflection;
+using System.Security.Cryptography;
 using System.Text.Json;
 using System.Text.Json.Nodes;
 using Aspire.Hosting.ApplicationModel;
 using Aspire.Hosting.Azure.Provisioning;
+using Aspire.Hosting.Azure.Utils;
 using Aspire.Hosting.Lifecycle;
 using Azure;
 using Azure.Core;
@@ -362,14 +364,44 @@ private async Task<ProvisioningContext> GetProvisioningContextAsync(Lazy<Task<Js
             throw new MissingConfigurationException("An azure location/region is required. Set the Azure:Location configuration value.");
         }
 
-        var unique = $"{Environment.MachineName.ToLowerInvariant()}-{environment.ApplicationName.ToLowerInvariant()}";
+        var userSecrets = await userSecretsLazy.Value.ConfigureAwait(false);
+
+        string resourceGroupName;
+        bool createIfAbsent;
 
-        // Name of the resource group to create based on the machine name and application name
-        var (resourceGroupName, createIfAbsent) = _options.ResourceGroup switch
+        if (string.IsNullOrEmpty(_options.ResourceGroup))
         {
-            null or { Length: 0 } => ($"rg-aspire-{unique}", true),
-            string rg => (rg, _options.AllowResourceGroupCreation ?? false)
-        };
+            // Generate an resource group name since none was provided
+
+            var prefix = "rg-aspire";
+
+            if (!string.IsNullOrWhiteSpace(_options.ResourceGroupPrefix))
+            {
+                prefix = _options.ResourceGroupPrefix;
+            }
+
+            var suffix = RandomNumberGenerator.GetHexString(8, lowercase: true);
+
+            var maxApplicationNameSize = ResourceGroupNameHelpers.MaxResourceGroupNameLength - prefix.Length - suffix.Length - 2; // extra '-'s
+
+            var normalizedApplicationName = ResourceGroupNameHelpers.NormalizeResourceGroupName(environment.ApplicationName.ToLowerInvariant());
+            if (normalizedApplicationName.Length > maxApplicationNameSize)
+            {
+                normalizedApplicationName = normalizedApplicationName[..maxApplicationNameSize];
+            }
+
+            // Create a unique resource group name and save it in user secrets
+            resourceGroupName = $"{prefix}-{normalizedApplicationName}-{suffix}";
+
+            createIfAbsent = true;
+
+            userSecrets.Prop("Azure")["ResourceGroup"] = resourceGroupName;
+        }
+        else
+        {
+            resourceGroupName = _options.ResourceGroup;
+            createIfAbsent = _options.AllowResourceGroupCreation ?? false;
+        }
 
         var resourceGroups = subscriptionResource.GetResourceGroups();
 
@@ -406,8 +438,6 @@ private async Task<ProvisioningContext> GetProvisioningContextAsync(Lazy<Task<Js
 
         var resourceMap = new Dictionary<string, ArmResource>();
 
-        var userSecrets = await userSecretsLazy.Value.ConfigureAwait(false);
-
         return new ProvisioningContext(
                     credential,
                     armClient,

src/Aspire.Hosting.Azure/Utils/ResourceGroupNameHelpers.cs

@@ -0,0 +1,58 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+using System.Globalization;
+using System.Text;
+
+namespace Aspire.Hosting.Azure.Utils;
+
+internal static class ResourceGroupNameHelpers
+{
+    public static int MaxResourceGroupNameLength = 90;
+
+    /// <summary>
+    /// Converts or excludes any characters which are not valid resource group name components.
+    /// </summary>
+    /// <param name="resourceGroupName">The text to normalize.</param>
+    /// <returns>The normalized resource group name or an empty string if no characters were valid.</returns>
+    public static string NormalizeResourceGroupName(string resourceGroupName)
+    {
+        resourceGroupName = RemoveDiacritics(resourceGroupName);
+
+        var stringBuilder = new StringBuilder(capacity: resourceGroupName.Length);
+
+        for (var i = 0; i < resourceGroupName.Length; i++)
+        {
+            var c = resourceGroupName[i];
+
+            if (!char.IsAsciiLetterOrDigit(c) && c != '-' && c != '_')
+            {
+                continue;
+            }
+
+            stringBuilder.Append(c);
+        }
+
+        return stringBuilder.ToString();
+    }
+
+    private static string RemoveDiacritics(string text)
+    {
+        var normalizedString = text.Normalize(NormalizationForm.FormD);
+        var stringBuilder = new StringBuilder(capacity: normalizedString.Length);
+
+        for (var i = 0; i < normalizedString.Length; i++)
+        {
+            var c = normalizedString[i];
+            var unicodeCategory = CharUnicodeInfo.GetUnicodeCategory(c);
+            if (unicodeCategory != UnicodeCategory.NonSpacingMark)
+            {
+                stringBuilder.Append(c);
+            }
+        }
+
+        return stringBuilder
+            .ToString()
+            .Normalize(NormalizationForm.FormC);
+    }
+}

tests/Aspire.Hosting.Tests/Azure/ResourceGroupNameHelpersTests.cs

@@ -0,0 +1,25 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+using Aspire.Hosting.Azure.Utils;
+using Xunit;
+
+namespace Aspire.Hosting.Tests.Azure;
+
+public class ResourceGroupNameHelpersTests
+{
+    [Theory]
+    [InlineData("äæǽåàçéïôùÀÇÉÏÔÙ", "aaaceiouACEIOU")]
+    [InlineData("🔥🤔😅🤘", "")]
+    [InlineData("こんにちは", "")]
+    [InlineData("", "")]
+    [InlineData("  ", "")]
+    [InlineData("-.()_", "-_")]
+    [InlineData("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789-_", "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789-_")]
+    public void ShouldCreateAzdCompatibleResourceGroupNames(string input, string expected)
+    {
+        var result = ResourceGroupNameHelpers.NormalizeResourceGroupName(input);
+
+        Assert.Equal(expected, result);
+    }
+}