WIP - KB declarative pattern external plugin

plugin/go.mod

@@ -0,0 +1,17 @@
+module sigs.k8s.io/kubebuilder-declarative-pattern/plugin
+
+go 1.19
+
+require (
+	github.com/spf13/afero v1.9.5
+	github.com/spf13/pflag v1.0.5
+	sigs.k8s.io/kubebuilder/v3 v3.10.0
+)
+
+require (
+	github.com/gobuffalo/flect v1.0.2 // indirect
+	golang.org/x/mod v0.10.0 // indirect
+	golang.org/x/sys v0.7.0 // indirect
+	golang.org/x/text v0.9.0 // indirect
+	golang.org/x/tools v0.8.0 // indirect
+)

plugin/main.go

@@ -0,0 +1,25 @@
+/*
+Copyright 2023 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 main
+
+import (
+	"sigs.k8s.io/kubebuilder-declarative-pattern/plugin/v1/cmd"
+)
+
+func main() {
+	cmd.Run()
+}

plugin/v1/cmd/cmd.go

@@ -0,0 +1,89 @@
+/*
+Copyright 2023 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 cmd
+
+import (
+	"bufio"
+	"encoding/json"
+	"fmt"
+	"io"
+	"log"
+	"os"
+
+	"sigs.k8s.io/kubebuilder-declarative-pattern/plugin/v1/scaffolds"
+	"sigs.k8s.io/kubebuilder/v3/pkg/plugin/external"
+)
+
+const (
+	commandInit  = "init"
+	commandApi   = "create api"
+	commandFlags = "flags"
+)
+
+func returnError(err error) {
+	response := external.PluginResponse{
+		Error:     true,
+		ErrorMsgs: []string{err.Error()},
+	}
+
+	output, err := json.Marshal(response)
+	if err != nil {
+		log.Fatalf("encountered error serializing output: %s | output: %s", err.Error(), output)
+	}
+	fmt.Printf("%s", output)
+}
+
+// Run will run the steps defined by the plugin
+func Run() {
+	// Kubebuilder makes requests to external plugin by writing STDIN.
+	reader := bufio.NewReader(os.Stdin)
+
+	input, err := io.ReadAll(reader)
+	if err != nil {
+		returnError(fmt.Errorf("encountered error reading from STDIN: %+v", err))
+	}
+
+	// Parsing request sent by kubebuilder into a PluginRequest instance.
+	pluginRequest := &external.PluginRequest{}
+
+	if err = json.Unmarshal(input, pluginRequest); err != nil {
+		returnError(err)
+	}
+
+	// Run logic based on the command executed by Kubebuilder.
+	var response external.PluginResponse
+	switch pluginRequest.Command {
+	case commandInit:
+		response = scaffolds.InitCmd(pluginRequest)
+	case commandApi:
+		response = scaffolds.ApiCmd(pluginRequest)
+	case commandFlags:
+		response = FlagsCmd(pluginRequest)
+	default:
+		response = external.PluginResponse{
+			Error:     true,
+			ErrorMsgs: []string{"unknown subcommand:" + pluginRequest.Command},
+		}
+	}
+
+	output, err := json.Marshal(response)
+	if err != nil {
+		returnError(err)
+	}
+
+	fmt.Printf("%s", output)
+}

plugin/v1/cmd/flags.go

@@ -0,0 +1,54 @@
+/*
+Copyright 2023 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 cmd
+
+import (
+	"github.com/spf13/pflag"
+	"sigs.k8s.io/kubebuilder-declarative-pattern/plugin/v1/scaffolds"
+	"sigs.k8s.io/kubebuilder/v3/pkg/plugin/external"
+)
+
+func FlagsCmd(pr *external.PluginRequest) external.PluginResponse {
+	pluginResponse := external.PluginResponse{
+		APIVersion: "v1",
+		Command:    "flags",
+		Universe:   pr.Universe,
+		Flags:      []external.Flag{},
+	}
+
+	flagsToParse := pflag.NewFlagSet("flags", pflag.ContinueOnError)
+	flagsToParse.Bool("init", false, "sets the init flag to true")
+	flagsToParse.Bool("api", false, "sets the api flag to true")
+
+	flagsToParse.Parse(pr.Args)
+
+	initFlag, _ := flagsToParse.GetBool("init")
+	apiFlag, _ := flagsToParse.GetBool("api")
+
+	if initFlag {
+		pluginResponse.Flags = scaffolds.InitFlags
+	} else if apiFlag {
+		pluginResponse.Flags = scaffolds.ApiFlags
+	} else {
+		pluginResponse.Error = true
+		pluginResponse.ErrorMsgs = []string{
+			"unrecognized flag",
+		}
+	}
+
+	return pluginResponse
+}

plugin/v1/scaffolds/api.go

@@ -0,0 +1,91 @@
+/*
+Copyright 2023 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 scaffolds
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+
+	"github.com/spf13/afero"
+	"sigs.k8s.io/kubebuilder-declarative-pattern/plugin/v1/scaffolds/internal/templates"
+	"sigs.k8s.io/kubebuilder/v3/pkg/machinery"
+	"sigs.k8s.io/kubebuilder/v3/pkg/plugin"
+	"sigs.k8s.io/kubebuilder/v3/pkg/plugin/external"
+)
+
+var ApiFlags = []external.Flag{}
+
+var ApiMeta = plugin.SubcommandMetadata{
+	Description: "Scaffold a Kubernetes API with the declarative plugin",
+	Examples:    "kubebuilder create api --plugins=go/v4,declarative/v1",
+}
+
+const (
+	exampleManifestVersion = "0.0.1"
+)
+
+// ApiCmd handles all the logic for the `create api` subcommand
+func ApiCmd(pr *external.PluginRequest) external.PluginResponse {
+	pluginResponse := external.PluginResponse{
+		Command:  "create api",
+		Universe: pr.Universe,
+	}
+
+	// TODO(@em-r): add logic for handling `create api` command
+	// GVK are required to scaffold templates, can be retrieved from PluginRequest.Args
+
+	return pluginResponse
+}
+
+func apiScaffold() error {
+	// Load the boilerplate
+	boilerplate, err := os.ReadFile(filepath.Join("hack", "boilerplate.go.txt"))
+	if err != nil {
+		return fmt.Errorf("error updating scaffold: unable to load boilerplate: %w", err)
+	}
+
+	fs := machinery.Filesystem{
+		FS: afero.NewOsFs(),
+	}
+
+	// Initialize the machinery.Scaffold that will write the files to disk
+	scaffold := machinery.NewScaffold(fs,
+		machinery.WithBoilerplate(string(boilerplate)),
+	)
+
+	//nolint:staticcheck
+	err = scaffold.Execute(
+		&templates.Types{},
+		&templates.Controller{},
+		&templates.Channel{ManifestVersion: exampleManifestVersion},
+		&templates.Manifest{ManifestVersion: exampleManifestVersion},
+	)
+
+	if err != nil {
+		return fmt.Errorf("error updating scaffold: %w", err)
+	}
+
+	// Update Dockerfile
+	// nolint:staticcheck
+	err = updateDockerfile()
+	if err != nil {
+		return err
+	}
+
+	return nil
+}

plugin/v1/scaffolds/init.go

@@ -0,0 +1,103 @@
+/*
+Copyright 2023 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 scaffolds
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"strings"
+
+	"sigs.k8s.io/kubebuilder/v3/pkg/plugin"
+	"sigs.k8s.io/kubebuilder/v3/pkg/plugin/external"
+	"sigs.k8s.io/kubebuilder/v3/pkg/plugin/util"
+)
+
+var InitFlags = []external.Flag{}
+
+var InitMeta = plugin.SubcommandMetadata{
+	Description: "Initialize a new project with declarative plugin",
+	Examples: `
+	Scaffold with go/v4:
+	$ kubebuilder init --plugins go/v4,declarative/v1
+	`,
+}
+
+// InitCmd handles all the logic for the `init` subcommand
+func InitCmd(pr *external.PluginRequest) external.PluginResponse {
+	pluginResponse := external.PluginResponse{
+		APIVersion: "v1",
+		Command:    "init",
+		Universe:   pr.Universe,
+	}
+
+	if err := updateDockerfile(); err != nil {
+		pluginResponse.Error = true
+		pluginResponse.ErrorMsgs = append(pluginResponse.ErrorMsgs, err.Error())
+	}
+
+	if content, err := os.ReadFile("Dockerfile"); err != nil {
+		pluginResponse.Error = true
+		pluginResponse.ErrorMsgs = append(pluginResponse.ErrorMsgs, err.Error())
+
+	} else {
+		pluginResponse.Universe["Dockerfile"] = string(content)
+	}
+
+	return pluginResponse
+}
+
+// updateDockerfile will add channels staging required for declarative plugin
+func updateDockerfile() error {
+	// fmt.Println("updating Dockerfile to add channels/ directory in the image")
+	dockerfile := filepath.Join("Dockerfile")
+	controllerPath := "internal/controller/"
+
+	// nolint:lll
+	err := insertCodeIfDoesNotExist(dockerfile,
+		fmt.Sprintf("COPY %s %s", controllerPath, controllerPath),
+		"\n# https://github.com/kubernetes-sigs/kubebuilder-declarative-pattern/blob/master/docs/addon/walkthrough/README.md#adding-a-manifest\n# Stage channels and make readable\nCOPY channels/ /channels/\nRUN chmod -R a+rx /channels/")
+	if err != nil {
+		return err
+	}
+
+	err = insertCodeIfDoesNotExist(dockerfile,
+		"COPY --from=builder /workspace/manager .",
+		"\n# copy channels\nCOPY --from=builder /channels /channels\n")
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+// insertCodeIfDoesNotExist insert code if it does not already exists
+func insertCodeIfDoesNotExist(filename, target, code string) error {
+	// false positive
+	// nolint:gosec
+	contents, err := os.ReadFile(filename)
+	if err != nil {
+		return err
+	}
+
+	idx := strings.Index(string(contents), code)
+	if idx != -1 {
+		return nil
+	}
+
+	return util.InsertCode(filename, target, code)
+}