feat(webhook-generator): add mutation webhook configs.

Author: Christoph Bühler

src/KubeOps.Cli/Commands/Generator/WebhookOperatorGenerator.cs

@@ -176,47 +176,91 @@ internal static async Task Handler(IAnsiConsole console, InvocationContext ctx)
             { Exists: false } => throw new FileNotFoundException($"The file {file.Name} does not exist."),
             _ => throw new NotSupportedException("Only *.csproj and *.sln files are supported."),
         };
-        var validatedEntities = parser.GetValidatedEntities().ToList();
+
+        var caBundle = Encoding.ASCII.GetBytes(Convert.ToBase64String(Encoding.ASCII.GetBytes(caCert.ToPem())));
+
+        var validationWebhooks = parser.GetValidatedEntities().ToList();
         var validatorConfig = new V1ValidatingWebhookConfiguration(
             metadata: new V1ObjectMeta(name: "validators"),
             webhooks: new List<V1ValidatingWebhook>()).Initialize();
 
-        foreach (var entity in validatedEntities)
+        foreach (var hook in validationWebhooks)
         {
             validatorConfig.Webhooks.Add(new V1ValidatingWebhook
             {
-                Name = $"validate.{entity.Metadata.SingularName}.{entity.Metadata.Group}.{entity.Metadata.Version}",
+                Name = $"validate.{hook.Metadata.SingularName}.{hook.Metadata.Group}.{hook.Metadata.Version}",
                 MatchPolicy = "Exact",
                 AdmissionReviewVersions = new[] { "v1" },
                 SideEffects = "None",
                 Rules = new[]
                 {
                     new V1RuleWithOperations
                     {
-                        Operations = entity.GetOperations(),
-                        Resources = new[] { entity.Metadata.PluralName },
-                        ApiGroups = new[] { entity.Metadata.Group },
-                        ApiVersions = new[] { entity.Metadata.Version },
+                        Operations = hook.GetOperations(),
+                        Resources = new[] { hook.Metadata.PluralName },
+                        ApiGroups = new[] { hook.Metadata.Group },
+                        ApiVersions = new[] { hook.Metadata.Version },
                     },
                 },
                 ClientConfig = new Admissionregistrationv1WebhookClientConfig
                 {
-                    CaBundle =
-                        Encoding.ASCII.GetBytes(Convert.ToBase64String(Encoding.ASCII.GetBytes(caCert.ToPem()))),
+                    CaBundle = caBundle,
                     Service = new Admissionregistrationv1ServiceReference
                     {
-                        Name = "operator", Path = entity.ValidatorPath,
+                        Name = "operator",
+                        Path = hook.WebhookPath,
                     },
                 },
             });
         }
 
-        if (validatedEntities.Any())
+        if (validationWebhooks.Any())
         {
             result.Add(
                 $"validators.{format.ToString().ToLowerInvariant()}", validatorConfig);
         }
 
+        var mutationWebhooks = parser.GetMutatedEntities().ToList();
+        var mutatorConfig = new V1MutatingWebhookConfiguration(
+            metadata: new V1ObjectMeta(name: "mutators"),
+            webhooks: new List<V1MutatingWebhook>()).Initialize();
+
+        foreach (var hook in mutationWebhooks)
+        {
+            mutatorConfig.Webhooks.Add(new V1MutatingWebhook
+            {
+                Name = $"mutate.{hook.Metadata.SingularName}.{hook.Metadata.Group}.{hook.Metadata.Version}",
+                MatchPolicy = "Exact",
+                AdmissionReviewVersions = new[] { "v1" },
+                SideEffects = "None",
+                Rules = new[]
+                {
+                    new V1RuleWithOperations
+                    {
+                        Operations = hook.GetOperations(),
+                        Resources = new[] { hook.Metadata.PluralName },
+                        ApiGroups = new[] { hook.Metadata.Group },
+                        ApiVersions = new[] { hook.Metadata.Version },
+                    },
+                },
+                ClientConfig = new Admissionregistrationv1WebhookClientConfig
+                {
+                    CaBundle = caBundle,
+                    Service = new Admissionregistrationv1ServiceReference
+                    {
+                        Name = "operator",
+                        Path = hook.WebhookPath,
+                    },
+                },
+            });
+        }
+
+        if (mutationWebhooks.Any())
+        {
+            result.Add(
+                $"mutators.{format.ToString().ToLowerInvariant()}", mutatorConfig);
+        }
+
         result.Add(
             $"kustomization.{format.ToString().ToLowerInvariant()}",
             new KustomizationConfig
@@ -229,6 +273,9 @@ internal static async Task Handler(IAnsiConsole console, InvocationContext ctx)
                         validatorConfig.Webhooks.Any()
                             ? $"validators.{format.ToString().ToLowerInvariant()}"
                             : string.Empty,
+                        mutatorConfig.Webhooks.Any()
+                            ? $"mutators.{format.ToString().ToLowerInvariant()}"
+                            : string.Empty,
                     }.Where(s => !string.IsNullOrWhiteSpace(s)).ToList(),
                 CommonLabels = new Dictionary<string, string> { { "operator-element", "operator-instance" }, },
                 ConfigMapGenerator = new List<KustomizationConfigMapGenerator>

src/KubeOps.Cli/Transpilation/AssemblyLoader.cs

@@ -6,6 +6,7 @@
 
 using KubeOps.Abstractions.Entities.Attributes;
 using KubeOps.Abstractions.Rbac;
+using KubeOps.Operator.Web.Webhooks.Mutation;
 using KubeOps.Operator.Web.Webhooks.Validation;
 using KubeOps.Transpiler;
 
@@ -165,13 +166,21 @@ public static IEnumerable<CustomAttributeData> GetRbacAttributes(this MetadataLo
         }
     }
 
-    public static IEnumerable<ValidatedEntity> GetValidatedEntities(this MetadataLoadContext context) => context
+    public static IEnumerable<ValidationWebhook> GetValidatedEntities(this MetadataLoadContext context) => context
         .GetAssemblies()
         .SelectMany(a => a.DefinedTypes)
         .Where(t => t.BaseType?.Name == typeof(ValidationWebhook<>).Name &&
                     t.BaseType?.Namespace == typeof(ValidationWebhook<>).Namespace)
         .Distinct()
-        .Select(t => new ValidatedEntity(t, context.ToEntityMetadata(t.BaseType!.GenericTypeArguments[0]).Metadata));
+        .Select(t => new ValidationWebhook(t, context.ToEntityMetadata(t.BaseType!.GenericTypeArguments[0]).Metadata));
+
+    public static IEnumerable<MutationWebhook> GetMutatedEntities(this MetadataLoadContext context) => context
+        .GetAssemblies()
+        .SelectMany(a => a.DefinedTypes)
+        .Where(t => t.BaseType?.Name == typeof(MutationWebhook<>).Name &&
+                    t.BaseType?.Namespace == typeof(MutationWebhook<>).Namespace)
+        .Distinct()
+        .Select(t => new MutationWebhook(t, context.ToEntityMetadata(t.BaseType!.GenericTypeArguments[0]).Metadata));
 
     [GeneratedRegex(".*")]
     private static partial Regex DefaultRegex();

src/KubeOps.Cli/Transpilation/BaseWebhook.cs

@@ -0,0 +1,20 @@
+using System.Reflection;
+
+using KubeOps.Abstractions.Entities;
+
+namespace KubeOps.Cli.Transpilation;
+
+internal abstract record BaseWebhook(TypeInfo Webhook, EntityMetadata Metadata)
+{
+    private bool HasCreate => Webhook.DeclaredMembers.Any(m => m.Name.StartsWith("Create"));
+
+    private bool HasUpdate => Webhook.DeclaredMembers.Any(m => m.Name.StartsWith("Update"));
+
+    private bool HasDelete => Webhook.DeclaredMembers.Any(m => m.Name.StartsWith("Delete"));
+
+    public abstract string WebhookPath { get; }
+
+    public string[] GetOperations() =>
+        new[] { HasCreate ? "CREATE" : null, HasUpdate ? "UPDATE" : null, HasDelete ? "DELETE" : null, }
+            .Where(o => o is not null).ToArray()!;
+}

src/KubeOps.Cli/Transpilation/MutationWebhook.cs

@@ -0,0 +1,11 @@
+using System.Reflection;
+
+using KubeOps.Abstractions.Entities;
+
+namespace KubeOps.Cli.Transpilation;
+
+internal record MutationWebhook(TypeInfo Validator, EntityMetadata Metadata) : BaseWebhook(Validator, Metadata)
+{
+    public override string WebhookPath =>
+        $"/mutate/{Validator.BaseType!.GenericTypeArguments[0].Name.ToLowerInvariant()}";
+}

src/KubeOps.Cli/Transpilation/ValidatedEntity.cs

@@ -0,0 +1,11 @@
+using System.Reflection;
+
+using KubeOps.Abstractions.Entities;
+
+namespace KubeOps.Cli.Transpilation;
+
+internal record ValidationWebhook(TypeInfo Validator, EntityMetadata Metadata) : BaseWebhook(Validator, Metadata)
+{
+    public override string WebhookPath =>
+        $"/validate/{Validator.BaseType!.GenericTypeArguments[0].Name.ToLowerInvariant()}";
+}