github.com/argoproj/argo-cd/v3@v3.2.1/util/kube/portforwarder.go (about)

     1  package kube
     2  
     3  import (
     4  	"bytes"
     5  	"context"
     6  	"fmt"
     7  	"net"
     8  	"net/http"
     9  	"os"
    10  
    11  	corev1 "k8s.io/api/core/v1"
    12  	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
    13  	"k8s.io/apimachinery/pkg/util/httpstream"
    14  	"k8s.io/client-go/kubernetes"
    15  	"k8s.io/client-go/tools/clientcmd"
    16  	"k8s.io/client-go/tools/portforward"
    17  	"k8s.io/client-go/transport/spdy"
    18  	cmdutil "k8s.io/kubectl/pkg/cmd/util"
    19  	"k8s.io/kubectl/pkg/util/podutils"
    20  
    21  	utilio "github.com/argoproj/argo-cd/v3/util/io"
    22  )
    23  
    24  func selectPodForPortForward(clientSet kubernetes.Interface, namespace string, podSelectors ...string) (*corev1.Pod, error) {
    25  	for _, podSelector := range podSelectors {
    26  		pods, err := clientSet.CoreV1().Pods(namespace).List(context.Background(), metav1.ListOptions{
    27  			LabelSelector: podSelector,
    28  		})
    29  		if err != nil {
    30  			return nil, err
    31  		}
    32  
    33  		for _, po := range pods.Items {
    34  			if po.Status.Phase == corev1.PodRunning && podutils.IsPodReady(&po) {
    35  				return &po, nil
    36  			}
    37  		}
    38  	}
    39  	return nil, fmt.Errorf("cannot find ready pod with selector: %v - use the --{component}-name flag in this command or set the environmental variable (Refer to https://argo-cd.readthedocs.io/en/stable/user-guide/environment-variables), to change the Argo CD component name in the CLI", podSelectors)
    40  }
    41  
    42  func PortForward(targetPort int, namespace string, overrides *clientcmd.ConfigOverrides, podSelectors ...string) (int, error) {
    43  	loadingRules := clientcmd.NewDefaultClientConfigLoadingRules()
    44  	loadingRules.DefaultClientConfig = &clientcmd.DefaultClientConfig
    45  	clientConfig := clientcmd.NewInteractiveDeferredLoadingClientConfig(loadingRules, overrides, os.Stdin)
    46  	config, err := clientConfig.ClientConfig()
    47  	if err != nil {
    48  		return -1, err
    49  	}
    50  
    51  	if namespace == "" {
    52  		namespace, _, err = clientConfig.Namespace()
    53  		if err != nil {
    54  			return -1, err
    55  		}
    56  	}
    57  
    58  	clientSet, err := kubernetes.NewForConfig(config)
    59  	if err != nil {
    60  		return -1, err
    61  	}
    62  
    63  	pod, err := selectPodForPortForward(clientSet, namespace, podSelectors...)
    64  	if err != nil {
    65  		return -1, err
    66  	}
    67  
    68  	url := clientSet.CoreV1().RESTClient().Post().
    69  		Resource("pods").
    70  		Namespace(pod.Namespace).
    71  		Name(pod.Name).
    72  		SubResource("portforward").URL()
    73  
    74  	transport, upgrader, err := spdy.RoundTripperFor(config)
    75  	if err != nil {
    76  		return -1, fmt.Errorf("could not create round tripper: %w", err)
    77  	}
    78  	dialer := spdy.NewDialer(upgrader, &http.Client{Transport: transport}, "POST", url)
    79  
    80  	// Reuse environment variable for kubectl to disable the feature flag, default is enabled.
    81  	if !cmdutil.PortForwardWebsockets.IsDisabled() {
    82  		tunnelingDialer, err := portforward.NewSPDYOverWebsocketDialer(url, config)
    83  		if err != nil {
    84  			return -1, fmt.Errorf("could not create tunneling dialer: %w", err)
    85  		}
    86  		// First attempt tunneling (websocket) dialer, then fallback to spdy dialer.
    87  		dialer = portforward.NewFallbackDialer(tunnelingDialer, dialer, func(err error) bool {
    88  			return httpstream.IsUpgradeFailure(err) || httpstream.IsHTTPSProxyError(err)
    89  		})
    90  	}
    91  
    92  	readyChan := make(chan struct{}, 1)
    93  	failedChan := make(chan error, 1)
    94  	out := new(bytes.Buffer)
    95  	errOut := new(bytes.Buffer)
    96  
    97  	ln, err := net.Listen("tcp", "localhost:0")
    98  	if err != nil {
    99  		return -1, err
   100  	}
   101  	port := ln.Addr().(*net.TCPAddr).Port
   102  	utilio.Close(ln)
   103  	forwarder, err := portforward.NewOnAddresses(dialer, []string{"localhost"}, []string{fmt.Sprintf("%d:%d", port, targetPort)}, context.Background().Done(), readyChan, out, errOut)
   104  	if err != nil {
   105  		return -1, err
   106  	}
   107  
   108  	go func() {
   109  		err = forwarder.ForwardPorts()
   110  		if err != nil {
   111  			failedChan <- err
   112  		}
   113  	}()
   114  	select {
   115  	case err = <-failedChan:
   116  		return -1, err
   117  	case <-readyChan:
   118  	}
   119  	if errOut.String() != "" {
   120  		return -1, fmt.Errorf("%s", errOut.String())
   121  	}
   122  	return port, nil
   123  }