纯golang爬虫实战(一）

纯golang爬取内网网站数据

参考https://blog.csdn.net/CrazyJavaPerson/article/details/81871649

难点一：需要登录，参考我的上一篇文章https://www.cnblogs.com/pu369/p/12201707.html，找到POST登录的url和Form Data，并且经测试可改用GET方式登录。

难点二：登录后访问时携带cookie.参考https://blog.csdn.net/liu_rong_fei/article/details/51820793  用resp.Cookies()可得到Cookies,还有https://www.cnblogs.com/cnsanshao/p/7084808.html，最后参考https://segmentfault.com/q/1010000005889328这里，决定还是用cookiejar和http.Client，这样后续请求client会自动将cookie加入

难点三：我只想保留文字，参考https://studygolang.com/articles/9360去掉html标签

上代码（密码用XX代替了，根据网站特点，主要是URL参数变化且是连续数字，只需写个循环访问即可）

//纯golang爬虫
package main

import (
    "fmt"
    "io/ioutil"
    "net/http"
    "net/http/cookiejar"
    "regexp"
    "strings"
)

type MySpider struct {
    indexUrl string
    cleint   *http.Client
}

//登录，用GET代替POST请求
func (this MySpider) login() (string, error) {
    resp, err := this.cleint.Get("http://192.168.13.1:8080/")
    defer resp.Body.Close()
    resp, err = this.cleint.Get("http://192.168.13.1:8080/login/auth?name=XX&password=XX&scurity=s&type=0&typeField=0")
    body, err := ioutil.ReadAll(resp.Body)
    fmt.Print(string(body))
    resp, err = this.cleint.Get("http://192.168.13.1:8080/browse/basicinfo_p.jsp?rtpage=psnfrm&pid=00000164&func=0297&userbase=Usr")
    body, err = ioutil.ReadAll(resp.Body)
    fmt.Print(string(body))
    trimbody := []byte(trimHtml(string(body)))
    //保存到文件
    err = ioutil.WriteFile("test.txt", trimbody, 0644)

    resp, err = http.Get(this.indexUrl)
    if err != nil {
        return "err", err
    }
    defer resp.Body.Close()
    body, err = ioutil.ReadAll(resp.Body)
    //fmt.Print(resp.Cookies())
    if err != nil {
        return "err", err
    }
    return string(body), err
}

//运行
func (this MySpider) run() string {
    //生成可复用的client
    var client http.Client
    jar, err := cookiejar.New(nil)
    if err != nil {
        panic(err)
    }
    client.Jar = jar
    this.cleint = &client
    //登录，用GET代替POST请求
    this.login()
    return ""
}
func trimHtml(src string) string {
    //将HTML标签全转换成小写
    re, _ := regexp.Compile("\<[\S\s]+?\>")
    src = re.ReplaceAllStringFunc(src, strings.ToLower)
    //去除STYLE
    re, _ = regexp.Compile("\<style[\S\s]+?\</style\>")
    src = re.ReplaceAllString(src, "")
    //去除SCRIPT
    re, _ = regexp.Compile("\<script[\S\s]+?\</script\>")
    src = re.ReplaceAllString(src, "")
    //去除所有尖括号内的HTML代码，并换成换行符
    re, _ = regexp.Compile("\<[\S\s]+?\>")
    src = re.ReplaceAllString(src, "
")
    //去除连续的换行符
    re, _ = regexp.Compile("\s{2,}")
    src = re.ReplaceAllString(src, "
")
    return strings.TrimSpace(src)
}

func main() {
    //爬虫实例
    ms := new(MySpider)
    //入口地址http://192.168.13.1:8080
    ms.indexUrl = "http://192.168.13.1:8080"
    ms.run()
}