golang爬虫系列1

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这是一个创建于的文章，其中的信息可能已经有所发展或是发生改变。

经历

这里只是获取一个主页的新闻，找到其中的链接，进去读取每页的文章，本来参考文章是存储到数据库，我这边使用mysql，是8版本的mysql，windows下使用异常，在阿里云下面使用没有什么问题，用本地的navcat可以连接处理，但是用golang源码的“github.com/go-sql-driver/mysql”库使用就出现连接异常，不是那个密码格式改了的问题，后面就把对应的内容存储到本地文件，每个链接存储为一篇文章，但是可能有些链接会重复，用了去重处理。

去重代码

func removeCopySlice(list []string) []string {
    result := make([]string, 0, len(list))
    temp := map[string]struct{}{}
    for _, value := range list {
        if _, ok := temp[value]; !ok {
            temp[value] = struct{}{}
            result = append(result, value)
        }
    }
    return result
}

完整代码

package main

import (
    "fmt"
    "github.com/PuerkitoBio/goquery"
    "log"
    "net/http"
    "os"
    "regexp"
    "strconv"
    "sync"
    "time"
)

func main() {
    url := "https://www.gamersky.com/news/"
    resp, err := http.Get(url)
    if err != nil {
        log.Fatal(err) //出现错误时直接退出
    }
    defer resp.Body.Close()
    if resp.StatusCode != 200 {
        log.Fatalf("status code error: %d %s", resp.StatusCode, resp.Status)
    }
    //NewDocumentFromReader returns a Document from an io.Reader
    html, err := goquery.NewDocumentFromReader(resp.Body)

    var newList []string
    newList = getNewsLists(html, newList)
    fmt.Println("new:", len(newList))
    newnewList := removeCopySlice(newList)
    fmt.Println("newnew:", len(newnewList))

    var wg sync.WaitGroup
    for i := 0; i < len(newnewList); i++ {
        wg.Add(1)
        go getNews(newnewList[i], &wg)
    }
    wg.Wait()

}

func removeCopySlice(list []string) []string {
    result := make([]string, 0, len(list))
    temp := map[string]struct{}{}
    for _, value := range list {
        if _, ok := temp[value]; !ok {
            temp[value] = struct{}{}
            result = append(result, value)
        }
    }
    return result
}

func getNewsLists(html *goquery.Document, newList []string) []string {
    html.Find("a[class=tt]").Each(func(i int, selection *goquery.Selection) {
        url, _ := selection.Attr("href")
        newList = append(newList, url)
    })
    return newList
}

type News struct {
    Title   string
    Media   string
    Url     string
    PubTime string
    Content string
}

func getNews(url string, wg *sync.WaitGroup) {
    resp, err := http.Get(url)
    if err != nil {
        log.Println(err)
        wg.Done()
        return
    }
    defer resp.Body.Close()

    if resp.StatusCode != http.StatusOK {
        log.Printf("Error:status code %d", resp.StatusCode)
        wg.Done()
        return
    }
    html, err := goquery.NewDocumentFromReader(resp.Body)
    news := News{}

    html.Find("div[class=Mid2L_tit]>h1").Each(func(i int, selection *goquery.Selection) {
        news.Title = selection.Text()
    })
    if news.Title == "" {
        wg.Done()
        return
    }

    var tempTime string
    html.Find("div[class=detail]").Each(func(i int, selection *goquery.Selection) {
        tempTime = selection.Text()
    })
    reg := regexp.MustCompile(`\d+`)
    timeString := reg.FindAllString(tempTime, -1)
    news.PubTime = fmt.Sprintf("%s-%s-%s %s:%s:%s", timeString[0], timeString[1], timeString[2], timeString[3], timeString[4], timeString[5])

    html.Find("div[class=Mid2L_con]>p").Each(func(i int, selection *goquery.Selection) {
        news.Content = news.Content + selection.Text()
    })

    //db := mysql2.DBCon()
    //
    //stmt,err:=db.Prepare(
    //  "insert into game gamesky (`title`,`url`,`media`,`content`,`pub_time`) values (?,?,?,?,?)")
    //if err!=nil{
    //  log.Println(err)
    //  wg.Done()
    //}
    //defer stmt.Close()
    //
    //rs,err:=stmt.Exec(news.Title,news.Url,news.Media,news.Content,news.PubTime)
    //if err != nil{
    //  log.Println(err)
    //  wg.Done()
    //}
    //if id,_:=rs.LastInsertId();id>0{
    //  log.Println("插入成功")
    //}
    writeFile(news, wg)
    wg.Done()

}

//func writeFile(content string) {
func writeFile(news News, wg *sync.WaitGroup) {
    fmt.Println(news.Title)
    fmt.Println(news.Url)
    fmt.Println(news.PubTime)
    fmt.Println(time.Now().Unix())
    fmt.Println(strconv.FormatInt(time.Now().UnixNano(), 10))
    curentPath, _ := os.Getwd()
    //dirpath := curentPath + "\\" + "game" + string(time.Now().Unix())
    dirpath := curentPath + "\\" + news.Title + strconv.FormatInt(time.Now().UnixNano(), 10)
    filePath := dirpath + ".txt"
    fmt.Println("filePath", filePath)
    //if checkFileIsExist(filePath) {
    //  err := os.Remove(filePath)
    //  log.Fatal(err)
    //}
    file, _ := os.OpenFile(filePath, os.O_CREATE|os.O_WRONLY|os.O_APPEND, 0777)
    n, _ := file.WriteString(news.Title)
    //var file *os.File
    //file, _ = os.Create(filePath)
    //n, _ := io.WriteString(file, news.Title)
    defer file.Close()
    if n == 0 {
        wg.Done()
        return
    }
    //io.WriteString(file, news.Url)
    //io.WriteString(file, news.PubTime)
    file.WriteString("\n")
    file.WriteString(news.Url)
    file.WriteString("\n")
    file.WriteString(news.PubTime)
    file.WriteString("\n")
    file.WriteString(news.Content)

}

func checkFileIsExist(filePath string) bool {
    _, err := os.Stat(filePath)
    if err != nil {
        return false
    }

    return true
}

package mysql

import (
    "database/sql"
    "fmt"
    _ "github.com/go-sql-driver/mysql"
    "os"
)

var db *sql.DB

func init() {
    db, _ := sql.Open("mysql", "root:password@tcp(ipaddr:3306)/game_news?charset=utf8")
    //db, _ := sql.Open("mysql", "root:password@tcp(127.0.0.1:3306)/game?charset=utf8")
    db.SetMaxIdleConns(1000)
    err := db.Ping()
    if err != nil {
        fmt.Println("Failed to connect to mysql,err:" + err.Error())
        os.Exit(1)
    }

}

func DBCon() *sql.DB {
    return db
}

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