go-爬虫-百度贴吧（并发版）

爬取百度贴吧的网页

非并发版

package main

import (
	"fmt"
	"io"
	"net/http"
	"os"
	"strconv"
)

func HttpGet(url string) (result string, err error) {
	//	var result string
	resp, err1 := http.Get(url)
	if err1 != nil {
		err = err1
		return
	}
	defer resp.Body.Close()

	buf := make([]byte, 4096)
	for {
		n, err2 := resp.Body.Read(buf)
		if n == 0 {
			fmt.Println("读取网页完成")
			break
		}
		if err2 != nil && err2 != io.EOF {
			err = err2
			return
		}
		result += string(buf[:n])
	}
	return
}

func working(start, end int) {
	fmt.Printf("正在爬取第%d到第%d页", start, end)
	//爬取每一个网页
	for i := start; i <= end; i++ {
		url := "https://tieba.baidu.com/f?kw=vue&ie=utf-8&pn=" + strconv.Itoa((i-1)*50)
		result, err := HttpGet(url)
		if err != nil {
			fmt.Println("httpGet err", err)
			continue
		}
		//		fmt.Println("result", result)
		f, err := os.Create("第" + strconv.Itoa(i) + "页" + ".html")
		if err != nil {
			fmt.Println("HttpGet err", err)
			continue
		}
		f.WriteString(result)
		f.Close()
	}
}

func main() {
	var start, end int
	fmt.Print("请输入起始页。。。")
	fmt.Scan(&start)
	fmt.Print("请输入终止页。。。")
	fmt.Scan(&end)

	working(start, end)
}

并发版

这个只是在上面的基础上加了管道和开了协程

package main

import (
	"fmt"
	"io"
	"net/http"
	"os"
	"strconv"
)

func HttpGet(url string) (result string, err error) {
	//	var result string
	resp, err1 := http.Get(url)
	if err1 != nil {
		err = err1
		return
	}
	defer resp.Body.Close()

	buf := make([]byte, 4096)
	for {
		n, err2 := resp.Body.Read(buf)
		if n == 0 {
			fmt.Println("读取网页完成\n")
			break
		}
		if err2 != nil && err2 != io.EOF {
			err = err2
			return
		}
		result += string(buf[:n])
	}
	return
}

func SpiderPage(index int, page chan int) {
	fmt.Printf("正在爬取第%d到页\n", index)
	//爬取每一个网页
	//	for i := start; i <= end; i++ {
	url := "https://tieba.baidu.com/f?kw=vue&ie=utf-8&pn=" + strconv.Itoa((index-1)*50)
	result, err := HttpGet(url)
	if err != nil {
		fmt.Println("httpGet err", err)
		return
	}
	//		fmt.Println("result", result)
	f, err := os.Create("第" + strconv.Itoa(index) + "页" + ".html")
	if err != nil {
		fmt.Println("HttpGet err", err)
		return
	}
	f.WriteString(result)
	f.Close()
	//	}

	page <- index
}

func working2(start, end int) {
	fmt.Printf("正在爬取第%d页到%d页\n", start, end)

	page := make(chan int)

	for i := start; i <= end; i++ {
		go SpiderPage(i, page)
	}

	for i := start; i <= end; i++ {
		fmt.Printf("第%d个页面爬取完成\n", <-page)
	}
}

func main() {
	var start, end int
	fmt.Print("请输入起始页。。。")
	fmt.Scan(&start)
	fmt.Print("请输入终止页。。。")
	fmt.Scan(&end)

	working2(start, end)
}