forwarder

README

Forwarder

A forwarder for forwarding kubernetes cluster service and pod programmatically.

Installation

go get github.com/loivis/k8s-port-forward

Usage

forwarding by kubeconfig path

package main

import (
	"github.com/loivis/k8s-port-forward"
)

func main() {
	options := []*forwarder.Option{
		{
			// the local port for forwarding
			LocalPort: 	8080,
			// the k8s pod port
			RemotePort: 80,
			// the forwarding service name
			ServiceName: "my-nginx-svc",
			// the k8s source string, eg: svc/my-nginx-svc po/my-nginx-666
			// the Source field will be parsed and override ServiceName or RemotePort field
			Source: "svc/my-nginx-66b6c48dd5-ttdb2",
			// namespace default is "default"
			Namespace: "default"
		},
		{
			// if local port isn't provided, forwarder will generate a random port number
			// LocalPort: 8081,
			//
			// if target port isn't provided, forwarder find the first container port of the pod or service
			// RemotePort: 80,
			Source: "po/my-nginx-66b6c48dd5-ttdb2",
		},
	}

	// it's to create a forwarder, and you need provide a path of kubeconfig
	// the path of kubeconfig, default is "~/.kube/config"
	fwds, err := forwarder.FromConfigPath(context.Background(), options, "./kubecfg")
	if err != nil {
		panic(err)
	}
	// remember to close the forwarding
	defer fwds.Close()
	// wait forwarding ready
	// the remote and local ports are listed
	ports, err := fwds.Ready()
	if err != nil {
		panic(err)
	}
	// ...

	// if you want to block the goroutine and listen IOStreams close signal, you can do as following:
	fwds.Wait()
}

forwarding embed kubeconfig

package main

//go:embed kubeconfig
var kubeconfigBytes []byte

func main() {
	options := []*forwarder.Option{
		{
			// LocalPort: 8080,
			// RemotePort:  80,
			ServiceName: "my-nginx-svc",
		},
	}
	// use kubeconfig bytes to config forward
	ret, err := forwarder.FromConfigBytes(context.Background(), options, kubeconfigBytes)
	if err != nil {
		panic(err)
	}
	// remember to close the forwarding
	defer ret.Close()
	// wait forwarding ready
	// the remote and local ports are listed
	ports, err := ret.Ready()
	if err != nil {
		panic(err)
	}
	fmt.Printf("ports: %+v\n", ports)
	// ...

	// if you want to block the goroutine and listen IOStreams close signal, you can do as following:
	ret.Wait()
}

If you want to learn more about forwarder, you can read example, test cases and source code.

Documentation

Index

• Variables
• type Forwarders
  • func FromConfigBytes(ctx context.Context, options []*Option, kubeconfigBytes []byte) (*Forwarders, error)
  • func FromConfigPath(ctx context.Context, options []*Option, kubeconfigPath string) (*Forwarders, error)
• type Option
• type PodOption

Variables

var (
	Quiet = true
)

Types

type Forwarders

type Forwarders struct {
	Close func()                                        // close the port forwarding
	Ready func() ([][]portforward.ForwardedPort, error) // block till the forwarding ready
	Wait  func()                                        // block and listen IOStreams close signal
}

func FromConfigBytes

func FromConfigBytes(ctx context.Context, options []*Option, kubeconfigBytes []byte) (*Forwarders, error)

FromConfigBytes returns Forwarders from kube config bytes.

func FromConfigPath

func FromConfigPath(ctx context.Context, options []*Option, kubeconfigPath string) (*Forwarders, error)

FromConfigPath returns Forwarders from kube config path.

type Option

type Option struct {
	LocalPort   int           // the local port for forwarding
	RemotePort  int           // the remote port port for forwarding
	Namespace   string        // the k8s namespace metadata
	PodName     string        // the k8s pod metadata
	ServiceName string        // the k8s service metadata
	Source      string        // the k8s source string, eg: svc/my-nginx-svc po/my-nginx-66b6c48dd5-ttdb2
	Timeout     time.Duration // returning error in case forwarding not ready after timeout duration
}

type PodOption

type PodOption struct {
	LocalPort int    // the local port for forwarding
	PodPort   int    // the k8s pod port
	Pod       v1.Pod // the k8s pod metadata
}