stop.go

package main

import (
	"encoding/json"
	"fmt"
	"io/ioutil"
	"os"
	"strconv"
	"syscall"

	"mydocker/constant"
	"mydocker/container"

	"github.com/pkg/errors"

	log "github.com/sirupsen/logrus"
)

func stopContainer(containerName string) {
	// 1. 根据容器名称获取对应 PID
	containerInfo, err := getContainerInfoByName(containerName)
	if err != nil {
		log.Errorf("Get container %s info error %v", containerName, err)
		return
	}
	pidInt, err := strconv.Atoi(containerInfo.Pid)
	if err != nil {
		log.Errorf("Conver pid from string to int error %v", err)
		return
	}
	// 2.发送SIGTERM信号
	if err = syscall.Kill(pidInt, syscall.SIGTERM); err != nil {
		log.Errorf("Stop container %s error %v", containerName, err)
		return
	}
	// 3.修改容器信息，将容器置为STOP状态，并清空PID
	containerInfo.Status = container.STOP
	containerInfo.Pid = " "
	newContentBytes, err := json.Marshal(containerInfo)
	if err != nil {
		log.Errorf("Json marshal %s error %v", containerName, err)
		return
	}
	// 4.重新写回存储容器信息的文件
	dirURL := fmt.Sprintf(container.InfoLocFormat, containerName)
	configFilePath := dirURL + container.ConfigName
	if err := ioutil.WriteFile(configFilePath, newContentBytes, constant.Perm0622); err != nil {
		log.Errorf("Write file %s error:%v", configFilePath, err)
	}
}

func getContainerInfoByName(containerName string) (*container.Info, error) {
	dirURL := fmt.Sprintf(container.InfoLocFormat, containerName)
	configFilePath := dirURL + container.ConfigName
	contentBytes, err := ioutil.ReadFile(configFilePath)
	if err != nil {
		return nil, errors.Wrapf(err, "read file %s", configFilePath)
	}
	var containerInfo container.Info
	if err = json.Unmarshal(contentBytes, &containerInfo); err != nil {
		return nil, err
	}
	return &containerInfo, nil
}

func removeContainer(containerName string) {
	containerInfo, err := getContainerInfoByName(containerName)
	if err != nil {
		log.Errorf("Get container %s info error %v", containerName, err)
		return
	}
	// 限制只能删除STOP状态的容器
	if containerInfo.Status != container.STOP {
		log.Errorf("Couldn't remove running container")
		return
	}
	dirURL := fmt.Sprintf(container.InfoLocFormat, containerName)
	if err := os.RemoveAll(dirURL); err != nil {
		log.Errorf("Remove file %s error %v", dirURL, err)
	}
	err = container.DeleteWorkSpace(containerInfo.Volume, containerName)
	if err != nil {
		log.Errorf("DeleteWorkSpace error %v", err)
	}
}