Pin github.com/googleapis/gnostic to v0.4.0

See https://github.com/google/gnostic/pull/155

vendor/github.com/googleapis/gnostic/extensions/extensions.go

@@ -1,4 +1,4 @@
-// Copyright 2017 Google LLC. All Rights Reserved.
+// Copyright 2017 Google Inc. 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.
@@ -12,53 +12,71 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package gnostic_extension_v1
+package openapiextension_v1
 
 import (
+	"fmt"
 	"io/ioutil"
-	"log"
 	"os"
 
 	"github.com/golang/protobuf/proto"
 	"github.com/golang/protobuf/ptypes"
 )
 
+type documentHandler func(version string, extensionName string, document string)
 type extensionHandler func(name string, yamlInput string) (bool, proto.Message, error)
 
-// Main implements the main program of an extension handler.
-func Main(handler extensionHandler) {
-	// unpack the request
+func forInputYamlFromOpenapic(handler documentHandler) {
 	data, err := ioutil.ReadAll(os.Stdin)
 	if err != nil {
-		log.Println("File error:", err.Error())
+		fmt.Println("File error:", err.Error())
 		os.Exit(1)
 	}
 	if len(data) == 0 {
-		log.Println("No input data.")
+		fmt.Println("No input data.")
 		os.Exit(1)
 	}
 	request := &ExtensionHandlerRequest{}
 	err = proto.Unmarshal(data, request)
 	if err != nil {
-		log.Println("Input error:", err.Error())
+		fmt.Println("Input error:", err.Error())
 		os.Exit(1)
 	}
-	// call the handler
-	handled, output, err := handler(request.Wrapper.ExtensionName, request.Wrapper.Yaml)
-	// respond with the output of the handler
-	response := &ExtensionHandlerResponse{
-		Handled: false, // default assumption
-		Errors:  make([]string, 0),
-	}
-	if err != nil {
-		response.Errors = append(response.Errors, err.Error())
-	} else if handled {
-		response.Handled = true
-		response.Value, err = ptypes.MarshalAny(output)
-		if err != nil {
-			response.Errors = append(response.Errors, err.Error())
-		}
-	}
+	handler(request.Wrapper.Version, request.Wrapper.ExtensionName, request.Wrapper.Yaml)
+}
+
+// ProcessExtension calles the handler for a specified extension.
+func ProcessExtension(handleExtension extensionHandler) {
+	response := &ExtensionHandlerResponse{}
+	forInputYamlFromOpenapic(
+		func(version string, extensionName string, yamlInput string) {
+			var newObject proto.Message
+			var err error
+
+			handled, newObject, err := handleExtension(extensionName, yamlInput)
+			if !handled {
+				responseBytes, _ := proto.Marshal(response)
+				os.Stdout.Write(responseBytes)
+				os.Exit(0)
+			}
+
+			// If we reach here, then the extension is handled
+			response.Handled = true
+			if err != nil {
+				response.Error = append(response.Error, err.Error())
+				responseBytes, _ := proto.Marshal(response)
+				os.Stdout.Write(responseBytes)
+				os.Exit(0)
+			}
+			response.Value, err = ptypes.MarshalAny(newObject)
+			if err != nil {
+				response.Error = append(response.Error, err.Error())
+				responseBytes, _ := proto.Marshal(response)
+				os.Stdout.Write(responseBytes)
+				os.Exit(0)
+			}
+		})
+
 	responseBytes, _ := proto.Marshal(response)
 	os.Stdout.Write(responseBytes)
 }