main.go

// Copyright 2020 Google LLC. All Rights Reserved.
//
// 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 (
	"flag"
	"path/filepath"
	"strings"

	"github.com/pubgo/protoc-gen-openapi/generator"
	"google.golang.org/protobuf/compiler/protogen"
	"google.golang.org/protobuf/types/pluginpb"
)

var conf = generator.Configuration{
	Version:         flag.String("version", "0.0.1", "version number text, e.g. 1.2.3"),
	Title:           flag.String("title", "", "name of the API"),
	Description:     flag.String("description", "", "description of the API"),
	Naming:          flag.String("naming", "json", `naming convention. Use "proto" for passing names directly from the proto files`),
	FQSchemaNaming:  flag.Bool("fq_schema_naming", false, `schema naming convention. If "true", generates fully-qualified schema names by prefixing them with the proto message package name`),
	EnumType:        flag.String("enum_type", "integer", `type for enum serialization. Use "string" for string-based serialization`),
	CircularDepth:   flag.Int("depth", 2, "depth of recursion for circular messages"),
	DefaultResponse: flag.Bool("default_response", true, `add default response. If "true", automatically adds a default response to operations which use the google.rpc.Status message. Useful if you use envoy or grpc-gateway to transcode as they use this type for their default error responses.`),
	OutputMode:      flag.String("output_mode", "merged", `output generation mode. By default, a single openapi.yaml is generated at the out folder. Use "source_relative' to generate a separate '[inputfile].openapi.yaml' next to each '[inputfile].proto'.`),
}

func main() {
	flag.Parse()

	protogen.Options{ParamFunc: flag.CommandLine.Set}.Run(func(plugin *protogen.Plugin) error {
		plugin.SupportedFeatures = uint64(pluginpb.CodeGeneratorResponse_FEATURE_PROTO3_OPTIONAL)

		if *conf.OutputMode == "source_relative" {
			for _, file := range plugin.Files {
				if !file.Generate {
					continue
				}

				outfileName := strings.TrimSuffix(file.Desc.Path(), filepath.Ext(file.Desc.Path())) + ".openapi.yaml"
				outputFile := plugin.NewGeneratedFile(outfileName, "")
				gen := generator.NewOpenAPIv3Generator(plugin, conf, []*protogen.File{file})
				if err := gen.Run(outputFile); err != nil {
					return err
				}
			}
		} else {
			outputFile := plugin.NewGeneratedFile("openapi.yaml", "")
			return generator.NewOpenAPIv3Generator(plugin, conf, plugin.Files).Run(outputFile)
		}
		return nil
	})
}