cmd/bpa-operator/vendor/github.com/googleapis/gnostic/extensions/extensions.go

   1 // Copyright 2017 Google Inc. All Rights Reserved.
   2 //
   3 // Licensed under the Apache License, Version 2.0 (the "License");
   4 // you may not use this file except in compliance with the License.
   5 // You may obtain a copy of the License at
   6 //
   7 //    http://www.apache.org/licenses/LICENSE-2.0
   8 //
   9 // Unless required by applicable law or agreed to in writing, software
  10 // distributed under the License is distributed on an "AS IS" BASIS,
  11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12 // See the License for the specific language governing permissions and
  13 // limitations under the License.
  14
  15 package openapiextension_v1
  16
  17 import (
  18         "fmt"
  19         "io/ioutil"
  20         "os"
  21
  22         "github.com/golang/protobuf/proto"
  23         "github.com/golang/protobuf/ptypes"
  24 )
  25
  26 type documentHandler func(version string, extensionName string, document string)
  27 type extensionHandler func(name string, yamlInput string) (bool, proto.Message, error)
  28
  29 func forInputYamlFromOpenapic(handler documentHandler) {
  30         data, err := ioutil.ReadAll(os.Stdin)
  31         if err != nil {
  32                 fmt.Println("File error:", err.Error())
  33                 os.Exit(1)
  34         }
  35         if len(data) == 0 {
  36                 fmt.Println("No input data.")
  37                 os.Exit(1)
  38         }
  39         request := &ExtensionHandlerRequest{}
  40         err = proto.Unmarshal(data, request)
  41         if err != nil {
  42                 fmt.Println("Input error:", err.Error())
  43                 os.Exit(1)
  44         }
  45         handler(request.Wrapper.Version, request.Wrapper.ExtensionName, request.Wrapper.Yaml)
  46 }
  47
  48 // ProcessExtension calles the handler for a specified extension.
  49 func ProcessExtension(handleExtension extensionHandler) {
  50         response := &ExtensionHandlerResponse{}
  51         forInputYamlFromOpenapic(
  52                 func(version string, extensionName string, yamlInput string) {
  53                         var newObject proto.Message
  54                         var err error
  55
  56                         handled, newObject, err := handleExtension(extensionName, yamlInput)
  57                         if !handled {
  58                                 responseBytes, _ := proto.Marshal(response)
  59                                 os.Stdout.Write(responseBytes)
  60                                 os.Exit(0)
  61                         }
  62
  63                         // If we reach here, then the extension is handled
  64                         response.Handled = true
  65                         if err != nil {
  66                                 response.Error = append(response.Error, err.Error())
  67                                 responseBytes, _ := proto.Marshal(response)
  68                                 os.Stdout.Write(responseBytes)
  69                                 os.Exit(0)
  70                         }
  71                         response.Value, err = ptypes.MarshalAny(newObject)
  72                         if err != nil {
  73                                 response.Error = append(response.Error, err.Error())
  74                                 responseBytes, _ := proto.Marshal(response)
  75                                 os.Stdout.Write(responseBytes)
  76                                 os.Exit(0)
  77                         }
  78                 })
  79
  80         responseBytes, _ := proto.Marshal(response)
  81         os.Stdout.Write(responseBytes)
  82 }