Merge pull request #81 from lestrrat/issue-79

Attempt to reorganize the conversion to protobuf

cmd/openapi2proto/main.go

@@ -1,44 +1,66 @@
 package main
 
 import (
+	"bytes"
 	"flag"
+	"fmt"
 	"io"
-	"log"
 	"os"
 
 	"github.com/NYTimes/openapi2proto"
+	"github.com/NYTimes/openapi2proto/compiler"
+	"github.com/NYTimes/openapi2proto/protobuf"
+	"github.com/pkg/errors"
 )
 
 func main() {
+	if err := _main(); err != nil {
+		fmt.Fprintf(os.Stderr, "error: %s", err)
+		os.Exit(1)
+	}
+}
+
+func _main() error {
 	specPath := flag.String("spec", "../../spec.yaml", "location of the swagger spec file")
-	annotate := flag.Bool("options", false, "include (google.api.http) options for grpc-gateway")
+	annotate := flag.Bool("annotate", false, "include (google.api.http) options for grpc-gateway")
 	outfile := flag.String("out", "", "the file to output the result to. Defaults to stdout if not set")
+	indent := flag.Int("indent", 4, "number of spaces used for indentation")
 	flag.Parse()
 
-	api, err := openapi2proto.LoadDefinition(*specPath)
-	if err != nil {
-		log.Fatal("unable to load spec: ", err)
-	}
-
-	out, err := openapi2proto.GenerateProto(api, *annotate)
-	if err != nil {
-		log.Fatal("unable to generate protobuf: ", err)
-	}
-
-	var writer io.Writer
-	writer = os.Stdout
-
+	var dst io.Writer = os.Stdout
 	if *outfile != "" {
 		f, err := os.Create(*outfile)
 		if err != nil {
-			log.Fatalf("Can't open output file (%v): %v", outfile, err)
+			return errors.Wrapf(err, `failed to open output file (%v)`, outfile)
 		}
 		defer f.Close()
-		writer = f
+		dst = f
+	}
+
+	var options []openapi2proto.Option
+	var encoderOptions []protobuf.Option
+	var compilerOptions []compiler.Option
+
+	compilerOptions = append(compilerOptions, compiler.WithAnnotation(*annotate))
+
+	if *indent > 0 {
+		var indentStr bytes.Buffer
+		for i := 0; i < *indent; i++ {
+			indentStr.WriteByte(' ')
+		}
+		encoderOptions = append(encoderOptions, protobuf.WithIndent(indentStr.String()))
+	}
+
+	if len(compilerOptions) > 0 {
+		options = append(options, openapi2proto.WithCompilerOptions(compilerOptions...))
+	}
+
+	if len(encoderOptions) > 0 {
+		options = append(options, openapi2proto.WithEncoderOptions(encoderOptions...))
 	}
 
-	_, err = writer.Write(out)
-	if err != nil {
-		log.Fatal("unable to write output to stdout: ", err)
+	if err := openapi2proto.Transpile(dst, *specPath, options...); err != nil {
+		return errors.Wrap(err, `failed to transpile`)
 	}
+	return nil
 }