Bing 的 API 有所改动，无法获取第二天的图片了，因此修改更新逻辑，减少耦合

db.go

@@ -7,7 +7,7 @@ import (
 )
 
 type inserter func(date, hdURL, uhdURL string) error
-type querier func(date string) (*picture, error)
+type querier func(num int) ([]picture, error)
 type validator func(date string) (bool, error)
 
 func newInserter(db *sql.DB) (inserter, error) {
@@ -22,20 +22,30 @@ func newInserter(db *sql.DB) (inserter, error) {
 }
 
 func newQuerier(db *sql.DB) querier {
-	return func(date string) (*picture, error) {
-		res := db.QueryRow("SELECT Date,HDURL,UHDURL FROM Pictures WHERE Date = ?", date)
-		tmp := &picture{}
-		err := res.Scan(&tmp.DATE, &tmp.HDURL, &tmp.UHDURL)
+	return func(num int) ([]picture, error) {
+		res, err := db.Query(
+			"SELECT Date,HDURL,UHDURL FROM Pictures ORDER BY id DESC LIMIT ?", num)
 		if err != nil {
 			return nil, err
 		}
-		return tmp, err
+
+		ret := make([]picture, 0, num)
+		tmp := picture{}
+		for res.Next() {
+			err = res.Scan(&tmp.DATE, &tmp.HDURL, &tmp.UHDURL)
+			if err != nil {
+				return nil, err
+			}
+			ret = append(ret, tmp)
+		}
+		return ret, nil
 	}
 }
 
 func newValidator(db *sql.DB) validator {
 	return func(date string) (bool, error) {
-		res := db.QueryRow(`SELECT IFNULL((SELECT Date FROM Pictures WHERE Date=?), "NULL")`, date)
+		res := db.QueryRow(
+			`SELECT IFNULL((SELECT Date FROM Pictures WHERE Date=?), "NULL")`, date)
 		var tmp string
 		err := res.Scan(&tmp)
 		if err == nil {

http.go

@@ -1,43 +1,16 @@
 package main
 
 import (
-	"errors"
 	"fmt"
 	"net/http"
-	"time"
 )
 
-func getPictureURL(q querier, res int) (string, error) {
-	pic, err := q(time.Now().Format("20060102"))
-	if err != nil {
-		return "", nil
-	}
-	switch res {
-	case 0:
-		return pic.HDURL, nil
-	case 1:
-		return pic.UHDURL, nil
-	default:
-		return "", errors.New("UnSupported Res")
-	}
-}
-
 func redirectToHD(w http.ResponseWriter, r *http.Request) {
-	URL, err := getPictureURL(dbquerier, 0)
-	if err != nil {
-		fmt.Fprint(w, err)
-		return
-	}
-	http.Redirect(w, r, URL, 301)
+	http.Redirect(w, r, picBuffer[0].HDURL, 302)
 }
 
 func redirectToUHD(w http.ResponseWriter, r *http.Request) {
-	URL, err := getPictureURL(dbquerier, 1)
-	if err != nil {
-		fmt.Fprint(w, err)
-		return
-	}
-	http.Redirect(w, r, URL, 301)
+	http.Redirect(w, r, picBuffer[0].UHDURL, 302)
 }
 
 func homePage(w http.ResponseWriter, r *http.Request) {

main.go

@@ -11,20 +11,34 @@ var dbinserter inserter
 var dbquerier querier
 var dbvalidator validator
 var conf config
+var picBuffer [7]picture
 
-func updatePic(i inserter, v validator) (err error) {
-	tmpPURL, tmpDATE, err := getPictureInfo(-1, 1, "zh-CN")
+func updetePicBuffer(q querier, num int) error {
+	tmp, err := q(num)
 	if err != nil {
-		return
+		return err
 	}
+	for index := 0; index < num; index++ {
+		picBuffer[index] = tmp[index]
+	}
+	return nil
+}
+
+func updatePic(i inserter, v validator) error {
+	tmpPURL, tmpDATE, err := getPictureInfo(-1, 9, "zh-CN")
+	if err != nil {
+		return err
+	}
+
 	tmpPICs := rewriteURL(tmpPURL, tmpDATE)
-	for _, tmpPIC := range tmpPICs {
+	for index := len(tmpPICs) - 1; index >= 0; index-- {
+		tmpPIC := tmpPICs[index]
 		status, _ := v(tmpPIC.DATE)
 		if status {
 			i(tmpPIC.DATE, tmpPIC.HDURL, tmpPIC.UHDURL)
 		}
 	}
-	return
+	return nil
 }
 
 func getDuration(hour int) time.Duration {
@@ -40,10 +54,11 @@ func getDuration(hour int) time.Duration {
 }
 
 func timeToUpdatePic() {
-	timer := time.NewTimer(time.Second * 10)
+	timer := time.NewTimer(0)
 	for {
 		<-timer.C
 		updatePic(dbinserter, dbvalidator)
+		updetePicBuffer(dbquerier, 7)
 		timer.Reset(getDuration(conf.UpdateTime))
 	}
 }
@@ -59,15 +74,20 @@ func init() {
 	}
 	dbquerier = newQuerier(db)
 	dbvalidator = newValidator(db)
-	readConf("./config.json", &conf)
-	fmt.Println(conf)
+	err = readConf("./config.json", &conf)
+	if err != nil {
+		panic("Open Config Error")
+	}
 	go timeToUpdatePic()
 }
 
 func main() {
 	http.HandleFunc("/", homePage)
 	http.HandleFunc("/HDRES/", redirectToHD)
 	http.HandleFunc("/UHDRES/", redirectToUHD)
+	time.Sleep(time.Second)
+	fmt.Println("Done")
+	fmt.Println(picBuffer)
 	if conf.EnableTLS {
 		http.ListenAndServeTLS("0.0.0.0:"+conf.Port,
 			conf.CertPath, conf.KeyPath, nil)