比较爬虫用的语言Python与Go

Python是我比较喜欢的语言，莫名的喜欢，对Python的学习可能起初是敲错了网址开始的，哈哈哈~

工作的任务从一个网站后台做登录、爬取数据，写入服务器Redis中，同事认为我会用PHP来写，哼！让你猜到那该多没意思，于是乎有了如下Python的代码，你看50多行搞定了。

#!/usr/bin/python3
import requests
import re
import redis
from pyquery import PyQuery as pq

loginUrl = 'https://manage.xxx.com.cn/home/login'
userName = 'xxx'
passWord = 'xxx'

redisServer = '192.168.0.2'
redisPort = 6379
redisPass = ''

productList = {'椰油':'CL_Spot','咖啡':'COFFEE','工业铜':'COPPER'}
volumeList = {'CL_Spot':[0, 0], 'COFFEE':[0, 0], 'COPPER':[0, 0]}

def main():
    jsessionid = getCookie()
    doLogin(jsessionid)
    dataUrl = 'https://manage.xxx.cn/?pageNo=1&pageSize=100'
    cookies = {'JSESSIONID': jsessionid}
    r = requests.get(dataUrl, cookies = cookies)
    dom = pq(r.text)
    lines = dom('table').eq(1).find('tr').items()
    for line in lines:
        line = re.sub(r'<!--.*-->', '', str(line))
        pattern = re.compile(r'<td>(.*?)</td>')
        group = pattern.findall(line)
        if not group:
            continue
        productCode = productList[group[3]]
        if group[6] == '买':
            volumeList[productCode][0]+= int(group[7]) * int(group[8])
        if group[6] == '卖':
            volumeList[productCode][1]+= int(group[7]) * int(group[8])

    redisClient = redis.Redis(host=redisServer, port=redisPort, password=redisPass)
    for x in volumeList:
        keyUp = 'redis_order_count_u_%s' % x
        keyDown = 'redis_order_count_d_%s' % x
        redisClient.set(keyUp, int(volumeList[x][0]))
        redisClient.set(keyDown, int(volumeList[x][1]))

def getCookie():
    ua = {'user-agent': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3538.110 Safari/537.36'}
    r = requests.get(loginUrl, headers = ua)
    return r.cookies['JSESSIONID']

def doLogin(jsessionid):
    param = {'userName': userName, 'password': passWord}
    cookies = {'JSESSIONID': jsessionid}
    requests.post(loginUrl, data = param, cookies = cookies)
    

if __name__ == '__main__':
    main()

另一个服务也需要这个需求，用了最近看的Golang来实现一次，瞧写了100多行

package main

import (
    "fmt"
    "net/http"
    "net/url"
    "os"
    "strings"
    "strconv"
    "gopkg.in/redis.v4"
    "github.com/PuerkitoBio/goquery"
)

var loginUrl string = "https://manage.xxx.com.cn/home/login"
var dataUrl string = "https://manage.xxx.com.cn/?pageNo=1&pageSize=100"
var userName string = "xxx"
var passWord string = "xxx"
var redisServer string = "192.168.1.2"
var redisPort string = "6379"
var redisPass string = ""
var redisDB   int = 0

func main() {
    productList := make(map[string] string)
    productList["椰油"] = "CL_Spot"
    productList["咖啡"] = "COFFEE"
    productList["工业铜"] = "COPPER"
    volumeList := make(map[string] int)
    volumeList["u_CL_Spot"] = 0
    volumeList["d_CL_Spot"] = 0
    volumeList["u_COFFEE"] = 0
    volumeList["d_COFFEE"] = 0
    volumeList["u_COPPER"] = 0
    volumeList["d_COPPER"] = 0
    jsessionid := getCookie()
    doLogin(jsessionid)

    request, err := http.NewRequest("GET", dataUrl, nil)
    request.AddCookie(&http.Cookie{Name: "JSESSIONID", Value: jsessionid})
    client := &http.Client{}
    response, err := client.Do(request)
    if err != nil {
        fmt.Println(err.Error())
        os.Exit(0)
    }
    defer response.Body.Close()
    doc, err := goquery.NewDocumentFromReader(response.Body)
    doc.Find("table").Eq(1).Find("tr").Each(func(i int, tr *goquery.Selection) {
        td := tr.Find("td")
        name := td.Eq(3).Text()
        dir := td.Eq(6).Text()
        if val, ok := productList[name]; ok {
            buyNum, _ := strconv.Atoi(td.Eq(7).Text())
            buyUnit, _ := strconv.Atoi(td.Eq(8).Text())
            num :=  buyNum * buyUnit
            cacheKey := ""
            if dir == "买" {
                cacheKey = fmt.Sprintf("u_%s", val)
            } else if dir == "卖" {
                cacheKey = fmt.Sprintf("d_%s", val)
            }
            volumeList[cacheKey] += num
        }
    })
    redisClient := redis.NewClient(&redis.Options{
        Addr:     fmt.Sprintf("%s:%s", redisServer, redisPort),
        Password: redisPass,
        DB:       redisDB,
    })
    for k, v := range volumeList {
        strKey := fmt.Sprintf("redis_order_count_%s", k)
        redisClient.Set(strKey, int(v), 0)
    }
    fmt.Println("puti volume get success")
}

func getCookie() string {
    jsessionid := ""
    response, err := http.Get(loginUrl)
    if err != nil {
        fmt.Println(err.Error())
        os.Exit(0)
    }
    defer response.Body.Close()
    for _, val := range response.Cookies() {
        if val.Name == "JSESSIONID" {
            jsessionid = val.Value
        }
    }
    return jsessionid
}

func doLogin(jsessionid string) bool {
    data := url.Values{}
    data.Set("userName", userName)
    data.Add("password", passWord)
    request, _ := http.NewRequest("POST", loginUrl, strings.NewReader(data.Encode()))
    request.Header.Add("Content-Type", "application/x-www-form-urlencoded")
    request.Header.Add("Content-Length", strconv.Itoa(len(data.Encode())))
    request.AddCookie(&http.Cookie{Name: "JSESSIONID", Value: jsessionid})
    client := &http.Client{}
    response, err := client.Do(request)
    if err != nil {
        fmt.Println(err.Error())
        os.Exit(0)
    }
    defer response.Body.Close()
    return true
}

Python的实现到上线半天的功夫搞定了，Go足足搞了1整天，蹩脚的语法与不熟悉的语法让我学习了很多知识点，最后Mac编译到Linux上执行也给我上了一课。

觉得入门学习这两门语言挺好，一个是脚本语言另一个是编译语言，用处都很广泛。轩轩你准备好了吗？