k8s.io/client-go@v0.31.1/tools/remotecommand/v4.go (about) 1 /* 2 Copyright 2016 The Kubernetes Authors. 3 4 Licensed under the Apache License, Version 2.0 (the "License"); 5 you may not use this file except in compliance with the License. 6 You may obtain a copy of the License at 7 8 http://www.apache.org/licenses/LICENSE-2.0 9 10 Unless required by applicable law or agreed to in writing, software 11 distributed under the License is distributed on an "AS IS" BASIS, 12 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 See the License for the specific language governing permissions and 14 limitations under the License. 15 */ 16 17 package remotecommand 18 19 import ( 20 "encoding/json" 21 "errors" 22 "fmt" 23 "strconv" 24 "sync" 25 26 metav1 "k8s.io/apimachinery/pkg/apis/meta/v1" 27 "k8s.io/apimachinery/pkg/util/remotecommand" 28 "k8s.io/client-go/util/exec" 29 ) 30 31 // streamProtocolV4 implements version 4 of the streaming protocol for attach 32 // and exec. This version adds support for exit codes on the error stream through 33 // the use of metav1.Status instead of plain text messages. 34 type streamProtocolV4 struct { 35 *streamProtocolV3 36 } 37 38 var _ streamProtocolHandler = &streamProtocolV4{} 39 40 func newStreamProtocolV4(options StreamOptions) streamProtocolHandler { 41 return &streamProtocolV4{ 42 streamProtocolV3: newStreamProtocolV3(options).(*streamProtocolV3), 43 } 44 } 45 46 func (p *streamProtocolV4) createStreams(conn streamCreator) error { 47 return p.streamProtocolV3.createStreams(conn) 48 } 49 50 func (p *streamProtocolV4) handleResizes() { 51 p.streamProtocolV3.handleResizes() 52 } 53 54 func (p *streamProtocolV4) stream(conn streamCreator) error { 55 if err := p.createStreams(conn); err != nil { 56 return err 57 } 58 59 // now that all the streams have been created, proceed with reading & copying 60 61 errorChan := watchErrorStream(p.errorStream, &errorDecoderV4{}) 62 63 p.handleResizes() 64 65 p.copyStdin() 66 67 var wg sync.WaitGroup 68 p.copyStdout(&wg) 69 p.copyStderr(&wg) 70 71 // we're waiting for stdout/stderr to finish copying 72 wg.Wait() 73 74 // waits for errorStream to finish reading with an error or nil 75 return <-errorChan 76 } 77 78 // errorDecoderV4 interprets the json-marshaled metav1.Status on the error channel 79 // and creates an exec.ExitError from it. 80 type errorDecoderV4 struct{} 81 82 func (d *errorDecoderV4) decode(message []byte) error { 83 status := metav1.Status{} 84 err := json.Unmarshal(message, &status) 85 if err != nil { 86 return fmt.Errorf("error stream protocol error: %v in %q", err, string(message)) 87 } 88 switch status.Status { 89 case metav1.StatusSuccess: 90 return nil 91 case metav1.StatusFailure: 92 if status.Reason == remotecommand.NonZeroExitCodeReason { 93 if status.Details == nil { 94 return errors.New("error stream protocol error: details must be set") 95 } 96 for i := range status.Details.Causes { 97 c := &status.Details.Causes[i] 98 if c.Type != remotecommand.ExitCodeCauseType { 99 continue 100 } 101 102 rc, err := strconv.ParseUint(c.Message, 10, 8) 103 if err != nil { 104 return fmt.Errorf("error stream protocol error: invalid exit code value %q", c.Message) 105 } 106 return exec.CodeExitError{ 107 Err: fmt.Errorf("command terminated with exit code %d", rc), 108 Code: int(rc), 109 } 110 } 111 112 return fmt.Errorf("error stream protocol error: no %s cause given", remotecommand.ExitCodeCauseType) 113 } 114 default: 115 return errors.New("error stream protocol error: unknown error") 116 } 117 118 return fmt.Errorf(status.Message) 119 }