| // Licensed to the Apache Software Foundation (ASF) under one or more |
| // contributor license agreements. See the NOTICE file distributed with |
| // this work for additional information regarding copyright ownership. |
| // The ASF licenses this file to You 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 kube |
| |
| import ( |
| "context" |
| "fmt" |
| "io" |
| "net/http" |
| "net/url" |
| "os" |
| ) |
| |
| import ( |
| v1 "k8s.io/api/core/v1" |
| |
| "k8s.io/client-go/rest" |
| |
| "k8s.io/client-go/tools/portforward" |
| |
| "k8s.io/client-go/transport/spdy" |
| ) |
| |
| import ( |
| "github.com/apache/dubbo-kubernetes/pkg/core/logger" |
| ) |
| |
| type PortForward struct { |
| podName string |
| namespace string |
| // localAddress and localPort form a local listening address, eg: localhost:8080 |
| localAddress string |
| localPort int |
| // port of the target pod |
| podPort int |
| stopCh chan struct{} |
| cfg *rest.Config |
| client *rest.RESTClient |
| } |
| |
| func (pf *PortForward) Run() error { |
| readyCh := make(chan struct{}, 1) |
| errCh := make(chan error, 1) |
| // start a goroutine to process portforward |
| go func() { |
| for { |
| select { |
| case <-pf.stopCh: |
| return |
| default: |
| // fail-fast is target pod is not running |
| if err := pf.inspectPodStatus(); err != nil { |
| errCh <- err |
| return |
| } |
| fwReq := pf.client.Post().Resource("pods").Namespace(pf.namespace).Name(pf.podName).SubResource("portforward") |
| kubeFw, err := pf.createKubePortForwarder(fwReq.URL(), readyCh) |
| if err != nil { |
| errCh <- err |
| return |
| } |
| // for lost connection to target pod scenario, ForwardPorts would return nil. |
| // so we put portforward processing in a loop. it would retry until user interrupts. |
| if err = kubeFw.ForwardPorts(); err != nil { |
| errCh <- err |
| return |
| } |
| logger.CmdSugar().Infof("lost connection to %s pod", pf.podName) |
| } |
| } |
| }() |
| |
| select { |
| case <-readyCh: |
| return nil |
| case err := <-errCh: |
| return fmt.Errorf("running portforward failed, err: %s", err) |
| } |
| } |
| |
| // inspectPodStatus check status of the target pod. If this pod is not running, fail fast. |
| func (pf *PortForward) inspectPodStatus() error { |
| podReq := pf.client.Get().Resource("pods").Namespace(pf.namespace).Name(pf.podName) |
| logger.CmdSugar().Info(podReq.URL().String()) |
| obj, err := podReq.Do(context.Background()).Get() |
| if err != nil { |
| return fmt.Errorf("get information of pod %s in %s namespace failed, err: %s", pf.podName, pf.namespace, err) |
| } |
| pod, ok := obj.(*v1.Pod) |
| if !ok { |
| return fmt.Errorf("wanted pod but got %T", obj) |
| } |
| if pod.Status.Phase != v1.PodRunning { |
| return fmt.Errorf("pod %s is not running. now it is %s", pf.podName, pod.Status.Phase) |
| } |
| return nil |
| } |
| |
| // createKubePortForwarder makes use of kube api to create PortForwarder. |
| // It needs readyCh to tell PortForward that kube PortForwarder is ready. |
| func (pf *PortForward) createKubePortForwarder(reqUrl *url.URL, readyCh chan struct{}) (*portforward.PortForwarder, error) { |
| trans, upgrader, err := spdy.RoundTripperFor(pf.cfg) |
| if err != nil { |
| return nil, fmt.Errorf("creating spdy RoundTripper failed, err: %s", err) |
| } |
| dialer := spdy.NewDialer(upgrader, &http.Client{Transport: trans}, "POST", reqUrl) |
| fw, err := portforward.NewOnAddresses( |
| dialer, |
| []string{pf.localAddress}, |
| []string{fmt.Sprintf("%d:%d", pf.localPort, pf.podPort)}, |
| pf.stopCh, |
| readyCh, |
| io.Discard, |
| os.Stderr, |
| ) |
| if err != nil { |
| return nil, fmt.Errorf("creating kube portforward failed, err: %s", err) |
| } |
| return fw, nil |
| } |
| |
| // Stop close stopCh and free up resources |
| func (pf *PortForward) Stop() { |
| close(pf.stopCh) |
| } |
| |
| // Wait wait for closing stopCh which means that Stop function is the only way to trigger |
| func (pf *PortForward) Wait() { |
| <-pf.stopCh |
| } |
| |
| func NewPortForward(podName, namespace, localAddress string, localPort, podPort int, cfg *rest.Config) (*PortForward, error) { |
| pf := &PortForward{ |
| podName: podName, |
| namespace: namespace, |
| localAddress: localAddress, |
| localPort: localPort, |
| podPort: podPort, |
| stopCh: make(chan struct{}), |
| cfg: cfg, |
| } |
| cli, err := rest.RESTClientFor(cfg) |
| if err != nil { |
| return nil, err |
| } |
| pf.client = cli |
| return pf, nil |
| } |