Add delete api and delete webhook commands

Add delete functionality to remove APIs and webhooks from projects.
Users can now clean up scaffolded resources with proper validation.

Author: camilamacedo86

docs/book/src/plugins/extending/extending_cli_features_and_plugins.md

@@ -62,7 +62,9 @@ of the following CLI commands:
 - `init`: Initializes the project structure.
 - `create api`: Scaffolds a new API and controller.
 - `create webhook`: Scaffolds a new webhook.
-- `edit`: edit the project structure.
+- `delete api`: Deletes an API and its associated files.
+- `delete webhook`: Deletes a webhook and its associated files.
+- `edit`: Updates the project structure.
 
 Here’s an example of using the `init` subcommand with a custom plugin:
 

docs/book/src/plugins/extending/external-plugins.md

@@ -120,6 +120,8 @@ External plugins can support the following Kubebuilder subcommands:
 - `init`: Project initialization
 - `create api`: Scaffold Kubernetes API definitions
 - `create webhook`: Scaffold Kubernetes webhooks
+- `delete api`: Delete Kubernetes API definitions and associated files
+- `delete webhook`: Delete Kubernetes webhooks and associated files
 - `edit`: Update project configuration
 
 **Optional subcommands for enhanced user experience:**

docs/book/src/plugins/plugins.md

@@ -31,6 +31,10 @@ kubebuilder create api --plugins=pluginA,pluginB,pluginC
 OR
 kubebuilder create webhook --plugins=pluginA,pluginB,pluginC
 OR
+kubebuilder delete api --plugins=pluginA,pluginB,pluginC
+OR
+kubebuilder delete webhook --plugins=pluginA,pluginB,pluginC
+OR
 kubebuilder edit --plugins=pluginA,pluginB,pluginC
 ```
 

pkg/cli/cli.go

@@ -519,6 +519,15 @@ func (c *CLI) addSubcommands() {
 		c.cmd.AddCommand(createCmd)
 	}
 
+	// kubebuilder delete
+	deleteCmd := c.newDeleteCmd()
+	// kubebuilder delete api
+	deleteCmd.AddCommand(c.newDeleteAPICmd())
+	deleteCmd.AddCommand(c.newDeleteWebhookCmd())
+	if deleteCmd.HasSubCommands() {
+		c.cmd.AddCommand(deleteCmd)
+	}
+
 	// kubebuilder edit
 	c.cmd.AddCommand(c.newEditCmd())
 

pkg/cli/delete.go

@@ -0,0 +1,29 @@
+/*
+Copyright 2026 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package cli
+
+import (
+	"github.com/spf13/cobra"
+)
+
+func (CLI) newDeleteCmd() *cobra.Command {
+	return &cobra.Command{
+		Use:   "delete",
+		Short: "Delete a Kubernetes API or webhook",
+		Long:  `Delete a Kubernetes API or webhook and associated files.`,
+	}
+}

pkg/cli/delete_api.go

@@ -0,0 +1,67 @@
+/*
+Copyright 2026 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package cli
+
+import (
+	"fmt"
+
+	"github.com/spf13/cobra"
+
+	"sigs.k8s.io/kubebuilder/v4/pkg/plugin"
+)
+
+const deleteAPIErrorMsg = "failed to delete API"
+
+func (c CLI) newDeleteAPICmd() *cobra.Command {
+	cmd := &cobra.Command{
+		Use:   "api",
+		Short: "Delete a Kubernetes API",
+		Long: `Delete a Kubernetes API and its associated files.
+`,
+		RunE: errCmdFunc(
+			fmt.Errorf("api subcommand requires an existing project"),
+		),
+	}
+
+	// In case no plugin was resolved, instead of failing the construction of the CLI, fail the execution of
+	// this subcommand. This allows the use of subcommands that do not require resolved plugins like help.
+	if len(c.resolvedPlugins) == 0 {
+		cmdErr(cmd, noResolvedPluginError{})
+		return cmd
+	}
+
+	// Obtain the plugin keys and subcommands from the plugins that implement plugin.DeleteAPI.
+	subcommands := c.filterSubcommands(
+		func(p plugin.Plugin) bool {
+			_, isValid := p.(plugin.DeleteAPI)
+			return isValid
+		},
+		func(p plugin.Plugin) plugin.Subcommand {
+			return p.(plugin.DeleteAPI).GetDeleteAPISubcommand()
+		},
+	)
+
+	// Verify that there is at least one remaining plugin.
+	if len(subcommands) == 0 {
+		cmdErr(cmd, noAvailablePluginError{"API deletion"})
+		return cmd
+	}
+
+	c.applySubcommandHooks(cmd, subcommands, deleteAPIErrorMsg, false)
+
+	return cmd
+}

pkg/cli/delete_webhook.go

@@ -0,0 +1,67 @@
+/*
+Copyright 2026 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package cli
+
+import (
+	"fmt"
+
+	"github.com/spf13/cobra"
+
+	"sigs.k8s.io/kubebuilder/v4/pkg/plugin"
+)
+
+const deleteWebhookErrorMsg = "failed to delete webhook"
+
+func (c CLI) newDeleteWebhookCmd() *cobra.Command {
+	cmd := &cobra.Command{
+		Use:   "webhook",
+		Short: "Delete a webhook for an API resource",
+		Long: `Delete a webhook for an API resource and associated files.
+`,
+		RunE: errCmdFunc(
+			fmt.Errorf("webhook subcommand requires an existing project"),
+		),
+	}
+
+	// In case no plugin was resolved, instead of failing the construction of the CLI, fail the execution of
+	// this subcommand. This allows the use of subcommands that do not require resolved plugins like help.
+	if len(c.resolvedPlugins) == 0 {
+		cmdErr(cmd, noResolvedPluginError{})
+		return cmd
+	}
+
+	// Obtain the plugin keys and subcommands from the plugins that implement plugin.DeleteWebhook.
+	subcommands := c.filterSubcommands(
+		func(p plugin.Plugin) bool {
+			_, isValid := p.(plugin.DeleteWebhook)
+			return isValid
+		},
+		func(p plugin.Plugin) plugin.Subcommand {
+			return p.(plugin.DeleteWebhook).GetDeleteWebhookSubcommand()
+		},
+	)
+
+	// Verify that there is at least one remaining plugin.
+	if len(subcommands) == 0 {
+		cmdErr(cmd, noAvailablePluginError{"webhook deletion"})
+		return cmd
+	}
+
+	c.applySubcommandHooks(cmd, subcommands, deleteWebhookErrorMsg, false)
+
+	return cmd
+}

pkg/config/interface.go

@@ -82,6 +82,11 @@ type Config interface {
 	AddResource(res resource.Resource) error
 	// UpdateResource adds the provided resource if it was not present, modifies it if it was already present.
 	UpdateResource(res resource.Resource) error
+	// RemoveResource removes the resource matching the provided GVK from the config.
+	RemoveResource(gvk resource.GVK) error
+	// SetResourceWebhooks sets the webhook configuration for a resource, replacing existing configuration.
+	// Unlike UpdateResource which merges, this completely replaces the webhook config.
+	SetResourceWebhooks(gvk resource.GVK, webhooks *resource.Webhooks) error
 
 	// HasGroup checks if the provided group is the same as any of the tracked resources.
 	HasGroup(group string) bool

pkg/config/v3/config.go

@@ -259,6 +259,48 @@ func (c *Cfg) UpdateResource(res resource.Resource) error {
 	return nil
 }
 
+// RemoveResource implements config.Config
+func (c *Cfg) RemoveResource(gvk resource.GVK) error {
+	indexToRemove := -1
+	for i, r := range c.Resources {
+		// Match by Group, Version, Kind (not domain, as core types may not have domain set)
+		if r.Group == gvk.Group && r.Version == gvk.Version && r.Kind == gvk.Kind {
+			indexToRemove = i
+			break
+		}
+	}
+
+	if indexToRemove == -1 {
+		return fmt.Errorf("failed to remove resource: resource with GVK {%q %q %q} not found",
+			gvk.Group, gvk.Version, gvk.Kind)
+	}
+
+	// Remove the resource by slicing around it
+	c.Resources = append(c.Resources[:indexToRemove], c.Resources[indexToRemove+1:]...)
+	return nil
+}
+
+// SetResourceWebhooks implements config.Config
+func (c *Cfg) SetResourceWebhooks(gvk resource.GVK, webhooks *resource.Webhooks) error {
+	for i, r := range c.Resources {
+		// Match by Group, Version, Kind (not domain)
+		if r.Group == gvk.Group && r.Version == gvk.Version && r.Kind == gvk.Kind {
+			if webhooks == nil {
+				c.Resources[i].Webhooks = nil
+			} else {
+				if c.Resources[i].Webhooks == nil {
+					c.Resources[i].Webhooks = &resource.Webhooks{}
+				}
+				c.Resources[i].Webhooks.Set(webhooks)
+			}
+			return nil
+		}
+	}
+
+	return fmt.Errorf("failed to set webhooks: resource with GVK {%q %q %q} not found",
+		gvk.Group, gvk.Version, gvk.Kind)
+}
+
 // HasGroup implements config.Config
 func (c Cfg) HasGroup(group string) bool {
 	// Return true if the target group is found in the tracked resources

pkg/config/v3/config_test.go

@@ -276,6 +276,89 @@ var _ = Describe("Cfg", func() {
 			checkResource(c.Resources[0], resWithoutPlural)
 		})
 
+		It("RemoveResource should remove the resource if it exists", func() {
+			c.Resources = append(c.Resources, res)
+			l := len(c.Resources)
+			Expect(c.RemoveResource(res.GVK)).To(Succeed())
+			Expect(c.Resources).To(HaveLen(l - 1))
+			Expect(c.HasResource(res.GVK)).To(BeFalse())
+		})
+
+		It("RemoveResource should return an error if the resource does not exist", func() {
+			Expect(c.RemoveResource(res.GVK)).NotTo(Succeed())
+		})
+
+		It("RemoveResource should remove only the specified resource", func() {
+			res2 := resource.Resource{
+				GVK: resource.GVK{
+					Group:   "group",
+					Version: "v1",
+					Kind:    "OtherKind",
+				},
+			}
+			c.Resources = append(c.Resources, res, res2)
+			Expect(c.Resources).To(HaveLen(2))
+
+			Expect(c.RemoveResource(res.GVK)).To(Succeed())
+			Expect(c.Resources).To(HaveLen(1))
+			Expect(c.HasResource(res.GVK)).To(BeFalse())
+			Expect(c.HasResource(res2.GVK)).To(BeTrue())
+		})
+
+		It("SetResourceWebhooks should update webhook configuration", func() {
+			resWithWebhooks := resource.Resource{
+				GVK: resource.GVK{
+					Group:   "group",
+					Version: "v1",
+					Kind:    "Kind",
+				},
+				Webhooks: &resource.Webhooks{
+					WebhookVersion: "v1",
+					Defaulting:     true,
+					Validation:     true,
+				},
+			}
+			c.Resources = append(c.Resources, resWithWebhooks)
+
+			// Update to remove defaulting webhook
+			newWebhooks := &resource.Webhooks{
+				WebhookVersion: "v1",
+				Defaulting:     false,
+				Validation:     true,
+			}
+			Expect(c.SetResourceWebhooks(resWithWebhooks.GVK, newWebhooks)).To(Succeed())
+
+			updated, err := c.GetResource(resWithWebhooks.GVK)
+			Expect(err).NotTo(HaveOccurred())
+			Expect(updated.Webhooks.Defaulting).To(BeFalse())
+			Expect(updated.Webhooks.Validation).To(BeTrue())
+		})
+
+		It("SetResourceWebhooks should clear webhooks when nil provided", func() {
+			resWithWebhooks := resource.Resource{
+				GVK: resource.GVK{
+					Group:   "group",
+					Version: "v1",
+					Kind:    "Kind",
+				},
+				Webhooks: &resource.Webhooks{
+					WebhookVersion: "v1",
+					Defaulting:     true,
+				},
+			}
+			c.Resources = append(c.Resources, resWithWebhooks)
+
+			Expect(c.SetResourceWebhooks(resWithWebhooks.GVK, nil)).To(Succeed())
+
+			updated, err := c.GetResource(resWithWebhooks.GVK)
+			Expect(err).NotTo(HaveOccurred())
+			Expect(updated.Webhooks).To(BeNil())
+		})
+
+		It("SetResourceWebhooks should fail if resource not found", func() {
+			Expect(c.SetResourceWebhooks(res.GVK, nil)).NotTo(Succeed())
+		})
+
 		It("HasGroup should return false with no tracked resources", func() {
 			Expect(c.HasGroup(res.Group)).To(BeFalse())
 		})