获取bing每日壁纸地址和标题

图片url在body#bgImgProgLoad的data-ultra-definition-src属性上，标题在body#sh_cp的title属性上

下载bing背景图

获取到图片的url后还需要将其下载到本地。
GetImageName函数通过url获取图片的名字，为了防止重复下载可以先通过名字在本地找一下是否已经有相同名字的图片，当然名字也是可能重名，你可以加上当天日期。

记录下载的历史信息

每次下载的图片名字地址都会写入到json文件中作为一个记录，为了防止文件太大每个文件只写100条记录，超过了之后会通过日期写入新的文件中

源码如下：

package model

import (
	"encoding/json"
	"errors"
	"fmt"
	"io/ioutil"
	"net/http"
	"net/url"
	"ningtogo/configs"
	"ningtogo/tools/logger"
	"ningtogo/tools/util"
	"os"
	"path"
	"time"

	"github.com/PuerkitoBio/goquery"
)

type BingWallpaper struct {
	Title string `json:"title"`
	Url   string `json:"url"`
}

type Bing struct {
	Url      string
	Dir      string
	JsonPath string
}

const MAX_HIS_COUNT = 100

func GetImageName(imageUrl string) (string, error) {
	u, err := url.Parse(imageUrl)
	if err != nil {
		return "", err
	}
	names, exist := u.Query()["id"]
	if exist && len(names) > 0 {
		return names[0], nil
	}
	return "", errors.New("name not found")
}

func NewBing() *Bing {
	p := new(Bing)
	p.Url = "https://ningto.com/bing"
	p.Dir = configs.BingDir()
	p.JsonPath = path.Join(configs.BingDir(), "his.json")
	return p
}

func (p Bing) GetBingWallpaper() (BingWallpaper, error) {
	HOST := "https://cn.bing.com"
	result := BingWallpaper{}
	resp, err := http.Get(HOST)
	if err != nil {
		return result, err
	}
	defer resp.Body.Close()
	doc, err := goquery.NewDocumentFromReader(resp.Body)
	if err != nil {
		return result, err
	}

	wallpaperUrl := ""
	wallpaperTitle := ""
	doc.Find("body #bgImgProgLoad").Each(func(i int, s *goquery.Selection) {
		src, exist := s.Attr("data-ultra-definition-src")
		if exist {
			wallpaperUrl = HOST + src
		}
	})

	doc.Find("body #sh_cp").Each(func(i int, s *goquery.Selection) {
		wallpaperTitle, _ = s.Attr("title")
	})

	if len(wallpaperTitle) > 0 && len(wallpaperUrl) > 0 {
		result.Title = wallpaperTitle
		result.Url = wallpaperUrl
		return result, nil
	}
	return result, errors.New("invalid")
}

func (p Bing) Download() error {
	resp, err := http.Get(p.Url)
	if err != nil {
		return err
	}
	defer resp.Body.Close()

	var wallpaper BingWallpaper
	err = json.NewDecoder(resp.Body).Decode(&wallpaper)
	if err != nil {
		return err
	}

	name, err := GetImageName(wallpaper.Url)
	if err != nil {
		return err
	}

	imageLocalPath := path.Join(p.Dir, name)
	if util.PathExist(imageLocalPath) {
		logger.Info.Println("local image found", imageLocalPath)
		return nil
	}

	if err = p.Write(wallpaper); err != nil {
		logger.Error.Println("write failed", wallpaper)
		return err
	}

	imageResp, err := http.Get(wallpaper.Url)
	if err != nil {
		return err
	}
	defer imageResp.Body.Close()

	b, err := ioutil.ReadAll(imageResp.Body)
	if err != nil {
		return err
	}
	err = ioutil.WriteFile(path.Join(p.Dir, name), b, os.ModePerm)
	if err != nil {
		return err
	}

	return nil
}

func (p Bing) Write(data BingWallpaper) error {
	fmt.Println(data)
	b, err := ioutil.ReadFile(p.JsonPath)
	if err != nil {
		logger.Info.Println(err, p.JsonPath)
		// 忽略这个错误，第一次可能文件不存在
	}

	var dataList []BingWallpaper
	if len(b) > 0 {
		err = json.Unmarshal(b, &dataList)
		if err != nil {
			return err
		}
	}

	dataList = append(dataList, data)

	writeFile := func(path string, data []BingWallpaper) error {
		file, err := os.OpenFile(path, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, os.ModePerm)
		if err != nil {
			return err
		}
		defer file.Close()

		encoder := json.NewEncoder(file)
		encoder.SetEscapeHTML(false)
		encoder.SetIndent("", "  ")
		err = encoder.Encode(dataList)
		if err != nil {
			return err
		}
		return nil
	}

	if len(dataList) >= MAX_HIS_COUNT {
		bakPath := path.Join(p.Dir, "his_"+time.Now().Format("20060102")+".json")
		err = writeFile(bakPath, dataList)
		if err == nil {
			err = os.Remove(p.JsonPath)
		}
	} else {
		err = writeFile(p.JsonPath, dataList)
	}

	return err
}

go 获取bing壁纸地址

获取bing每日壁纸地址和标题

下载bing背景图

记录下载的历史信息