main.go

// Copyright 2021 The protobuf-tools Authors
// SPDX-License-Identifier: Apache-2.0

// Command protoc-gen-kube generates the Kubernetes controller APIs from Protocol Buffer schemas.
package main

import (
	"context"
	"fmt"
	"os"
	"path/filepath"

	"github.com/go-logr/logr"
	"github.com/go-logr/zapr"
	"github.com/spf13/pflag"
	"go.uber.org/zap"
	"google.golang.org/protobuf/compiler/protogen"
	"k8s.io/gengo/args"
	gengogenerator "k8s.io/gengo/generator"
	klog "k8s.io/klog/v2"

	"github.com/protobuf-tools/protoc-gen-kube/pkg/cmd"
	"github.com/protobuf-tools/protoc-gen-kube/pkg/generator"
	kubetypegen "github.com/protobuf-tools/protoc-gen-kube/pkg/generator/kubetype/generators"
	"github.com/protobuf-tools/protoc-gen-kube/pkg/generator/kubetype/scanner"
	"github.com/protobuf-tools/protoc-gen-kube/pkg/version"
)

var flagVersion bool

func main() {
	if err := gen(); err != nil {
		fmt.Fprintf(os.Stderr, "protoc-gen-kube: %v\n", err)
	}
}

func gen() error {
	z, err := zap.NewDevelopment()
	if err != nil {
		return fmt.Errorf("create zap development logger: %w", err)
	}

	// setup logr
	logf := zapr.NewLogger(z)
	ctx := logr.NewContext(context.Background(), logf)
	// inject third-party packages klog
	klog.SetLogger(logf)

	// setup *args.GeneratorArgs
	arg := args.Default()

	// setup flags
	pflag.BoolVarP(&flagVersion, "version", "v", false, fmt.Sprintf("print %s version", filepath.Base(os.Args[0])))
	arg.AddFlags(pflag.CommandLine)
	pflag.Parse()

	// show version if enabled -version flag
	if flagVersion {
		fmt.Fprintf(os.Stderr, "protoc-gen-kube@%s\n", version.Version())
		os.Exit(0)
	}

	// setup template
	arg.GeneratedByCommentTemplate = `// Code generated by ` + cmd.AppName + `. DO NOT EDIT.`
	// TODO(zchee): use it?
	arg.GoHeaderFilePath = filepath.Join(args.DefaultSourceTree(), "hack", "boilerplate", "boilerplate.go.txt")

	// execute
	builder, err := arg.NewBuilder()
	if err != nil {
		logf.Error(err, "create a builder")
		return fmt.Errorf("create a builder: %w", err)
	}

	// pass through the flag on whether to include *_test.go files
	arg.SetArgsToBuilder(builder)

	gctxt, err := gengogenerator.NewContext(builder, kubetypegen.NameSystems(" /* generatedPackage */ ", nil), kubetypegen.DefaultNameSystem())
	if err != nil {
		logf.Error(err, "create a generator context")
		return fmt.Errorf("create a generator context: %w", err)
	}

	// update generator.Context via args
	arg.SetArgsToContext(gctxt)

	// scan packages
	packages := scanner.New(ctx).Scan(gctxt, arg)
	_ = packages

	protogen.Options{
		ParamFunc: pflag.Set,
	}.Run(func(gen *protogen.Plugin) error {
		gen.SupportedFeatures = generator.SupportedFeatures

		req := gen.Request
		for _, pfile := range req.ProtoFile {
			sourceInfo := pfile.GetSourceCodeInfo()
			if sourceInfo == nil {
				continue
			}

			locs := sourceInfo.GetLocation()
			for _, loc := range locs {
				logf.Info("loc", "GetLeadingComments()", loc.GetLeadingComments())
				logf.Info("loc", "GetTrailingComments()", loc.GetTrailingComments())
			}
		}

		return nil
	})

	logf.Info("completed successfully")

	return nil
}