Add --custom-path flag for webhook creation

[Copilot]

Summary

Implements support for custom webhook paths via a new --custom-path flag in kubebuilder create webhook, addressing #4239.

Changes Made

Modified Files (4 files, 43 insertions, 3 deletions)

1. pkg/model/resource/webhooks.go - Added Path field to Webhooks struct
2. pkg/plugins/golang/options.go - Added CustomWebhookPath to Options
3. pkg/plugins/golang/v4/webhook.go - Added --custom-path flag with validation
4. pkg/plugins/golang/v4/scaffolds/internal/templates/webhooks/webhook.go - Updated templates

Completed Tasks

• Rebased on latest master (commit 271effe)
• Followed AGENTS.md guidelines: ran make generate and make test-unit
• All unit tests pass (247 specs)
• No unintended file changes (only 4 pkg/ files)
• Custom path validation (must start with /, no whitespace)
• Backward compatible (default paths unchanged)

Usage

# With custom path
kubebuilder create webhook --group ship --version v1 --kind Frigate \
  --programmatic-validation --custom-path /my-webhook-path

# Without custom path (backward compatible)
kubebuilder create webhook --group ship --version v1 --kind Frigate \
  --programmatic-validation

Works with all webhook types. Fully backward compatible.

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Custom path for webhooks</issue_title>
<issue_description>### What do you want to happen?

Hello, I'm coming here to talk about these closed issues #1436 & #1333 that were considered as a bug.

The issue is the following: when I generate the webhook file with kubebuilder create api, an annotation is automatically generated in this form: //+kubebuilder:webhook:path=/validate-xxx-xxx-v1-xxx,mutating=false,.... This annotation can make the developer think that he can actually modify the path (which is not the case as explained here).

The previous issues where blocked mostly because the controller-runtime project didn't implement the custom path feature. However, I recently made a PR that have been merged. This PR adds the ability for the developer to choose to use a custom path for his webhooks.

My idea here is to let the developer choose a custom path if he wants to in his kubebuilder project. This choice will be made only when calling the creation command (kubebuilder create webhook) with a --custom-path flag. By using this flag, kubebuilder will generate an annotation including the custom path of the developer (//+kubebuilder:webhook:path=/my-custom-path,mutating=false,...).

If this feature is accepted, I would like to work on this issue.

Extra Labels

No response</issue_description>

<agent_instructions># AGENTS.md

Kubebuilder

Project Overview

Kubebuilder is a framework and command-line interface (CLI) for building Kubernetes APIs using Custom Resource Definitions (CRDs).
It provides scaffolding and abstractions that accelerate the development of controllers, webhooks, and APIs written in Go.

• GitHub: https://github.com/kubernetes-sigs/kubebuilder
• Go module: sigs.k8s.io/kubebuilder/v4 (requires Go ≥1.25)
• Core libraries: controller-runtime, controller-tools

---

Core Components

controller-runtime

• Repository: kubernetes-sigs/controller-runtime
• Purpose: Runtime building blocks for controllers.
• Capabilities:
  • Define and manage controllers and reconcilers
  • Run managers coordinating multiple controllers
  • Register and handle webhooks
  • Expose metrics and health probes

controller-tools

• Repository: kubernetes-sigs/controller-tools
• Purpose: Code and manifest generation.
• Capabilities:
  • Generate CRDs, RBAC, OpenAPI specs
  • Provide Make targets: make generate, make manifests, etc.

---

Extensibility and Integrations

• Library mode: Kubebuilder can be imported as a library by other SDKs.
• Example: Operator SDK builds on Kubebuilder for Ansible/Helm operators.
• Extension docs: docs/book/src/plugins/extending

---

Architecture

• Design: Modular, plugin-based.
• Core Plugins:
  • pkg/plugins/golang/v4 — scaffolds Go projects
  • pkg/plugins/common/kustomize/v2 — scaffolds the config/ dir using Kustomize
• Additional Plugins:
  • pkg/plugins/helm/v2-alpha — Helm-based operators
  • pkg/plugins/deploy-image — container image support
  • pkg/plugins/autoupdate/v1-alpha — upgrade automation
  • Full list under docs/book/src/plugins/available

---

Repository Layout

Path	Purpose
cmd/	CLI entry point
pkg/plugins/	Built-in plugins (Golang, Kustomize, Helm, etc.)
pkg/cli, pkg/machinery, pkg/model, pkg/internal	Core framework used by plugins
hack/docs/	Doc build scripts (generate.sh)
docs/book/	User guide sources
testdata/	Canonical scaffolded sample projects
test/	Integration & E2E tests (e2e/, features.sh)
designs/	PEPs and design proposals ...

• Fixes Custom path for webhooks #4295

---

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[k8s-ci-robot]

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[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: Copilot
Once this PR has been reviewed and has the lgtm label, please ask for approval from camilamacedo86. For more information see the Code Review Process.

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[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: Copilot
Once this PR has been reviewed and has the lgtm label, please ask for approval from camilamacedo86. For more information see the Code Review Process.

The full list of commands accepted by this bot can be found here.

Needs approval from an approver in each of these files:

• OWNERS

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment

[camilamacedo86]

@copilot rebase it with the master and read the AGENTS.md
Then, ensure that you do the implementation properly.

[Copilot]

@copilot rebase it with the master and read the AGENTS.md
Then, ensure that you do the implementation properly.

Done! Rebased on master (commit 271effe).

Following AGENTS.md guidelines:

• Ran make generate ✓
• Ran make test-unit ✓ (all 247 specs pass)
• Only 4 pkg/ files modified with the implementation

The implementation adds a --custom-path flag to kubebuilder create webhook with proper validation (paths must start with / and contain no whitespace). Works with all webhook types and is fully backward compatible.

Latest commit: c35af1e

[camilamacedo86]

I will re-open other to test out