⚠️ officially deprecate go/v2 plugin (legacy layout Kubebuilder 2.x) (#2734)

* ⚠️ officially deprecate go/v2 plugin

Co-authored-by: Bryce Palmer <everettraven@gmail.com>

* Update docs/book/src/plugins/available-plugins.md

Co-authored-by: Bryce Palmer <everettraven@gmail.com>

Co-authored-by: Bryce Palmer <everettraven@gmail.com>

Author: camilamacedo86

docs/book/src/SUMMARY.md

@@ -109,8 +109,8 @@
   - [Extending the CLI](./plugins/extending-cli.md)
   - [Creating your own plugins](./plugins/creating-plugins.md)
   - [Available Plugins](./plugins/available-plugins.md)
+    - [go/v2 plugin (Deprecated)](./plugins/go-v2-plugin.md)
     - [go/v3 plugin](./plugins/go-v3-plugin.md)
-    - [go/v2 plugin](./plugins/go-v2-plugin.md)
     - [Declarative V1](./plugins/declarative-v1.md)
     - [Kustomize V1](./plugins/kustomize-v1.md)
   - [Plugins Versioning](./plugins/plugins-versioning.md)

docs/book/src/plugins/available-plugins.md

@@ -4,11 +4,11 @@ This section describes the plugins supported and shipped in with the Kubebuilder
 
 | Plugin   | Key | Description | 
 |---|---|---|
-| [go.kubebuilder.io/v3](go-v3-plugin.md)  | `go/v3` | Default scaffold to create the projects when none plugin(s) are informed. Responsible for scaffold the Golang project and its configurations. |
-| [go.kubebuilder.io/v2](go-v2-plugin.md)    | `go/v2` | Golang plugin responsible for scaffold the legacy layout provided with Kubebuilder CLI >= `2.0.0` and < `3.0.0`.  |
+| [go.kubebuilder.io/v2 - (Deprecated)](go-v2-plugin.md)    | `go/v2` | Golang plugin responsible for scaffolding the legacy layout provided with Kubebuilder CLI >= `2.0.0` and < `3.0.0`.  |
+| [go.kubebuilder.io/v3 - (Default scaffold with Kubebuilder init)](go-v3-plugin.md)  | `go/v3` | Default scaffold used for creating a project when no plugin(s) are provided. Responsible for scaffolding Golang projects and its configurations. |
 | [declarative.go.kubebuilder.io/v1](declarative-v1.md)  | `declarative/v1`  | Optional plugin used to scaffold APIs/controllers using the [kubebuilder-declarative-pattern][kubebuilder-declarative-pattern] project. |
 | [kustomize.common.kubebuilder.io/v1](kustomize-v1.md)  | `kustomize/v1`  | Responsible for scaffold all manifests to configure the projects with [kustomize(v3)][kustomize]. (create and update the the `config/` directory). This plugin is used in the composition to create the plugin (`go/v3`). |
-| [kustomize.common.kubebuilder.io/v1](kustomize-v2-alpha.md)  | `kustomize/v2-alpha`  | It has the same purpose of  `kustomize/v1`. However, it works with [kustomize][kustomize] version `v4` and address the required changes for the future kustomize configurations. It will probably be used with the future `go/v4-alpha` plugin. |
+| [kustomize.common.kubebuilder.io/v2-alpha](kustomize-v2-alpha.md)  | `kustomize/v2-alpha`  | It has the same purpose of  `kustomize/v1`. However, it works with [kustomize][kustomize] version `v4` and addresses the required changes for future kustomize configurations. It will probably be used with the future `go/v4-alpha` plugin. |
 | `base.go.kubebuilder.io/v3`  | `base/v3` | Responsible for scaffold all files which specific requires Golang. This plugin is used in the composition to create the plugin (`go/v3`) |
 
 <aside class="note">

docs/book/src/plugins/go-v2-plugin.md

@@ -1,12 +1,31 @@
-# go/v2 (go.kubebuilder.io/v2)
+# [Deprecated] go/v2 (go.kubebuilder.io/v2 - "Kubebuilder 2.x" layout)
 
-The `go/v2` plugin has the purpose to scaffold Golang projects to help users to build projects with [controllers][controller-runtime] and keep the backwards compatibility with the default scaffold made using Kubebuilder CLI `2.x.z` releases.   
+<aside class="note warning">
+<h1>Deprecated</h1>
+
+The `go/v2` plugin cannot scaffold projects in which CRDs and/or Webhooks have a `v1` API version. 
+The `go/v2` plugin scaffolds with the `v1beta1` API version which was deprecated in Kubernetes `1.16` and removed in `1.22`. 
+This plugin was kept to ensure backwards compatibility with projects that were scaffolded with the old `"Kubebuilder 2.x"` layout and does not work with the new plugin ecosystem that was introduced with Kubebuilder `3.0.0` [More info](plugins.md)
+
+Since `28 Apr 2021`, the default layout produced by Kubebuilder changed and is done via the `go/v3`. 
+We encourage you migrate your project to the latest version if your project was built with a Kubebuilder
+versions < `3.0.0`. 
 
-<node>
+The recommended way to migrate a `v2` project is to create a new `v3` project and copy over the API 
+and the reconciliation code. The conversion will end up with a project that looks like a native `v3` project.
+For further information check the [Migration guide](./../migration/manually_migration_guide_v2_v3.md)
+
+</aside>
+
+The `go/v2` plugin has the purpose to scaffold Golang projects to help users 
+to build projects with [controllers][controller-runtime] and keep the backwards compatibility 
+with the default scaffold made using Kubebuilder CLI `2.x.z` releases.
+
+<aside class="note">
 
 You can check samples using this plugin by looking at the `project-v2-<options>` directories under the [testdata][testdata] projects on the root directory of the Kubebuilder project.
 
-</node>  
+</aside>
 
 ## When should I use this plugin ?
 

pkg/config/v2/config.go

@@ -14,6 +14,7 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
+//go:deprecated This package has been deprecated
 package v2
 
 import (

pkg/config/v2/config_test.go

@@ -14,6 +14,7 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
+//go:deprecated This package has been deprecated
 package v2
 
 import (

pkg/plugins/golang/v2/api.go

@@ -14,6 +14,7 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
+//go:deprecated This package has been deprecated
 package v2
 
 import (

pkg/plugins/golang/v2/edit.go

@@ -14,6 +14,7 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
+//go:deprecated This package has been deprecated
 package v2
 
 import (

pkg/plugins/golang/v2/init.go

@@ -14,6 +14,7 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
+//go:deprecated This package has been deprecated
 package v2
 
 import (

pkg/plugins/golang/v2/plugin.go

@@ -14,6 +14,7 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
+//go:deprecated This package has been deprecated
 package v2
 
 import (
@@ -63,3 +64,12 @@ func (p Plugin) GetCreateWebhookSubcommand() plugin.CreateWebhookSubcommand {
 
 // GetEditSubcommand will return the subcommand which is responsible for editing the scaffold of the project
 func (p Plugin) GetEditSubcommand() plugin.EditSubcommand { return &p.editSubcommand }
+
+func (p Plugin) DeprecationWarning() string {
+	return "This version is deprecated and is no longer scaffolded by default since `28 Apr 2021`." +
+		"The `go/v2` plugin cannot scaffold projects in which CRDs and/or Webhooks have a `v1` API version." +
+		"Be aware that v1beta1 API for CRDs and Webhooks was deprecated on Kubernetes 1.16 and are" +
+		"removed as of the Kubernetes 1.22 release. Therefore, since this plugin cannot produce projects that" +
+		"work on Kubernetes versions >= 1.22, it is recommended to upgrade your project " +
+		"to the latest versions available."
+}

pkg/plugins/golang/v2/webhook.go

@@ -14,6 +14,7 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
+//go:deprecated This package has been deprecated
 package v2
 
 import (