prometheus/vendor/github.com/googleapis/gnostic/compiler/extension-handler.go
jojohappy 21e50a3f9d Upgrade k8s client to kubernetes-1.11.0
Signed-off-by: jojohappy <sarahdj0917@gmail.com>
2018-08-02 10:25:27 +08:00

102 lines
2.9 KiB
Go

// 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.
// 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 compiler
import (
"bytes"
"fmt"
"os/exec"
"strings"
"errors"
"github.com/golang/protobuf/proto"
"github.com/golang/protobuf/ptypes/any"
ext_plugin "github.com/googleapis/gnostic/extensions"
yaml "gopkg.in/yaml.v2"
)
// ExtensionHandler describes a binary that is called by the compiler to handle specification extensions.
type ExtensionHandler struct {
Name string
}
// HandleExtension calls a binary extension handler.
func HandleExtension(context *Context, in interface{}, extensionName string) (bool, *any.Any, error) {
handled := false
var errFromPlugin error
var outFromPlugin *any.Any
if context != nil && context.ExtensionHandlers != nil && len(*(context.ExtensionHandlers)) != 0 {
for _, customAnyProtoGenerator := range *(context.ExtensionHandlers) {
outFromPlugin, errFromPlugin = customAnyProtoGenerator.handle(in, extensionName)
if outFromPlugin == nil {
continue
} else {
handled = true
break
}
}
}
return handled, outFromPlugin, errFromPlugin
}
func (extensionHandlers *ExtensionHandler) handle(in interface{}, extensionName string) (*any.Any, error) {
if extensionHandlers.Name != "" {
binary, _ := yaml.Marshal(in)
request := &ext_plugin.ExtensionHandlerRequest{}
version := &ext_plugin.Version{}
version.Major = 0
version.Minor = 1
version.Patch = 0
request.CompilerVersion = version
request.Wrapper = &ext_plugin.Wrapper{}
request.Wrapper.Version = "v2"
request.Wrapper.Yaml = string(binary)
request.Wrapper.ExtensionName = extensionName
requestBytes, _ := proto.Marshal(request)
cmd := exec.Command(extensionHandlers.Name)
cmd.Stdin = bytes.NewReader(requestBytes)
output, err := cmd.Output()
if err != nil {
fmt.Printf("Error: %+v\n", err)
return nil, err
}
response := &ext_plugin.ExtensionHandlerResponse{}
err = proto.Unmarshal(output, response)
if err != nil {
fmt.Printf("Error: %+v\n", err)
fmt.Printf("%s\n", string(output))
return nil, err
}
if !response.Handled {
return nil, nil
}
if len(response.Error) != 0 {
message := fmt.Sprintf("Errors when parsing: %+v for field %s by vendor extension handler %s. Details %+v", in, extensionName, extensionHandlers.Name, strings.Join(response.Error, ","))
return nil, errors.New(message)
}
return response.Value, nil
}
return nil, nil
}