[Go] 并发imap收信

并发数太大会直接死,这里有时候需要多试几次

package mainimport ("flag""fmt""io/ioutil""log""math""os""sync""github.com/emersion/go-imap""github.com/emersion/go-imap/client"
)var (server, email, password stringworkernum               intimapClient              *client.ClientmailDirs                []stringmailSumNums             uint32pagesize                int = 50start                   intstop                    int
)type Pool struct {workerNum introad      chan *Carwg        sync.WaitGroup
}//初始化这个对象
func NewPool(wn int) *Pool {return &Pool{workerNum: wn, road: make(chan *Car)}
}//往channel添加具体任务
func (p *Pool) AddCar(f *Car) {p.road <- f
}//goroutine去工作
func (p *Pool) work(workId int) {for f := range p.road {log.Println("workId:", workId, "start")f.do()log.Println("workId:", workId, "done")}p.wg.Done()
}//创建goroutine等着接工作
func (p *Pool) Run() {for i := 0; i < p.workerNum; i++ {go p.work(i)p.wg.Add(1)}p.wg.Wait()
}func (p *Pool) colse() {close(p.road)
}var pool = NewPool(5)func main() {go handleMail()pool.Run()
}
func handleMail() {//获取命令行参数flag.StringVar(&server, "server", "", "imap服务地址(包含端口)")flag.StringVar(&email, "email", "", "邮箱名")flag.StringVar(&password, "password", "", "密码")flag.Parse()if flag.NFlag() < 3 {flag.PrintDefaults()os.Exit(1)}if server == "" || email == "" || password == "" {log.Fatal("服务器地址,用户名,密码,参数错误")}//连接imap服务imapClient, err := client.Dial(server)if err != nil {log.Fatal(err)}//登陆if err := imapClient.Login(email, password); err != nil {log.Fatal(err)}//创建邮件夹目录
    os.Mkdir(email, os.ModePerm)mailboxes := make(chan *imap.MailboxInfo, 20)go func() {imapClient.List("", "*", mailboxes)}()//列取邮件夹for m := range mailboxes {mailDirs = append(mailDirs, m.Name)}//循环邮件夹,创建邮件夹目录for _, mailDir := range mailDirs {//选中每个邮件夹mbox, err := imapClient.Select(mailDir, false)if err != nil {log.Fatal(err)}mailDirNums := mbox.Messageslog.Printf("%s : %d", mailDir, mailDirNums)fileDir := fmt.Sprintf("%s/%s", email, mailDir)//创建邮件夹目录
        os.Mkdir(fileDir, os.ModePerm)mailSumNums += mailDirNums}log.Printf("总邮件数 : %d", mailSumNums)//循环邮件夹,读取每个邮件夹中的邮件for _, mailDir := range mailDirs {//选中每个邮件夹mbox, err := imapClient.Select(mailDir, false)if err != nil {log.Fatal(err)}if mbox.Messages == 0{continue}//循环该邮件夹中的邮件pagecount := int(math.Ceil(float64(mbox.Messages) / float64(pagesize)))for i := 1; i <= pagecount; i++ {if i == 1 {start = 1} else {start = (i-1)*pagesize + 1}stop = i * pagesizeif stop > int(mbox.Messages) {stop = int(mbox.Messages)}car := Car{start:      start,stop:       stop,mailDir:    mailDir,imapClient: imapClient,}pool.AddCar(&car)}}pool.colse()
}/*具体做的事通过这个来传递*/
type Car struct {start, stop intmailDir     stringimapClient  *client.Client
}//具体做事
func (c *Car) do() error {seqset := new(imap.SeqSet)seqset.AddRange(uint32(c.start), uint32(c.stop))section := &imap.BodySectionName{}items := []imap.FetchItem{section.FetchItem()}messages := make(chan *imap.Message, pagesize)go func() {c.imapClient.Fetch(seqset, items, messages)}()for msg := range messages {mailFile := fmt.Sprintf("%s/%s/%d.eml", email, c.mailDir, msg.SeqNum)r := msg.GetBody(section)if r != nil {body, _ := ioutil.ReadAll(r)f, _ := os.OpenFile(mailFile, os.O_RDWR|os.O_CREATE, 0766)f.Write(body)f.Close()log.Printf("%s :第 %d ", c.mailDir, msg.SeqNum)}}return nil
}