优化按需抓取逻辑：改为异步处理以提升性能，并为相关接口新增 202 状态支持

internal/http/handlers/image.go

@@ -48,11 +48,16 @@ type ImageMetaResp struct {
 // @Param format query string false "格式 (jpg)" default(jpg)
 // @Produce image/jpeg
 // @Success 200 {file} binary
+// @Success 202 {object} map[string]string "按需抓取任务已启动"
 // @Failure 404 {object} map[string]string "图片未找到，响应体包含具体原因"
 // @Router /image/today [get]
 func GetToday(c *gin.Context) {
 	mkt := c.Query("mkt")
 	img, err := image.GetTodayImage(mkt)
+	if err == image.ErrFetchStarted {
+		c.JSON(http.StatusAccepted, gin.H{"message": fmt.Sprintf("On-demand fetch started for region [%s]. Please try again later.", mkt)})
+		return
+	}
 	if err != nil {
 		sendImageNotFound(c, mkt)
 		return
@@ -67,11 +72,16 @@ func GetToday(c *gin.Context) {
 // @Param mkt query string false "地区编码 (如 zh-CN, en-US)"
 // @Produce json
 // @Success 200 {object} ImageMetaResp
+// @Success 202 {object} map[string]string "按需抓取任务已启动"
 // @Failure 404 {object} map[string]string "图片未找到，响应体包含具体原因"
 // @Router /image/today/meta [get]
 func GetTodayMeta(c *gin.Context) {
 	mkt := c.Query("mkt")
 	img, err := image.GetTodayImage(mkt)
+	if err == image.ErrFetchStarted {
+		c.JSON(http.StatusAccepted, gin.H{"message": fmt.Sprintf("On-demand fetch started for region [%s]. Please try again later.", mkt)})
+		return
+	}
 	if err != nil {
 		sendImageNotFound(c, mkt)
 		return
@@ -89,11 +99,16 @@ func GetTodayMeta(c *gin.Context) {
 // @Param format query string false "格式" default(jpg)
 // @Produce image/jpeg
 // @Success 200 {file} binary
+// @Success 202 {object} map[string]string "按需抓取任务已启动"
 // @Failure 404 {object} map[string]string "图片未找到，响应体包含具体原因"
 // @Router /image/random [get]
 func GetRandom(c *gin.Context) {
 	mkt := c.Query("mkt")
 	img, err := image.GetRandomImage(mkt)
+	if err == image.ErrFetchStarted {
+		c.JSON(http.StatusAccepted, gin.H{"message": fmt.Sprintf("On-demand fetch started for region [%s]. Please try again later.", mkt)})
+		return
+	}
 	if err != nil {
 		sendImageNotFound(c, mkt)
 		return
@@ -108,11 +123,16 @@ func GetRandom(c *gin.Context) {
 // @Param mkt query string false "地区编码 (如 zh-CN, en-US)"
 // @Produce json
 // @Success 200 {object} ImageMetaResp
+// @Success 202 {object} map[string]string "按需抓取任务已启动"
 // @Failure 404 {object} map[string]string "图片未找到，响应体包含具体原因"
 // @Router /image/random/meta [get]
 func GetRandomMeta(c *gin.Context) {
 	mkt := c.Query("mkt")
 	img, err := image.GetRandomImage(mkt)
+	if err == image.ErrFetchStarted {
+		c.JSON(http.StatusAccepted, gin.H{"message": fmt.Sprintf("On-demand fetch started for region [%s]. Please try again later.", mkt)})
+		return
+	}
 	if err != nil {
 		sendImageNotFound(c, mkt)
 		return
@@ -131,12 +151,17 @@ func GetRandomMeta(c *gin.Context) {
 // @Param format query string false "格式" default(jpg)
 // @Produce image/jpeg
 // @Success 200 {file} binary
+// @Success 202 {object} map[string]string "按需抓取任务已启动"
 // @Failure 404 {object} map[string]string "图片未找到，响应体包含具体原因"
 // @Router /image/date/{date} [get]
 func GetByDate(c *gin.Context) {
 	date := c.Param("date")
 	mkt := c.Query("mkt")
 	img, err := image.GetImageByDate(date, mkt)
+	if err == image.ErrFetchStarted {
+		c.JSON(http.StatusAccepted, gin.H{"message": fmt.Sprintf("On-demand fetch started for region [%s]. Please try again later.", mkt)})
+		return
+	}
 	if err != nil {
 		sendImageNotFound(c, mkt)
 		return
@@ -152,12 +177,17 @@ func GetByDate(c *gin.Context) {
 // @Param mkt query string false "地区编码 (如 zh-CN, en-US)"
 // @Produce json
 // @Success 200 {object} ImageMetaResp
+// @Success 202 {object} map[string]string "按需抓取任务已启动"
 // @Failure 404 {object} map[string]string "图片未找到，响应体包含具体原因"
 // @Router /image/date/{date}/meta [get]
 func GetByDateMeta(c *gin.Context) {
 	date := c.Param("date")
 	mkt := c.Query("mkt")
 	img, err := image.GetImageByDate(date, mkt)
+	if err == image.ErrFetchStarted {
+		c.JSON(http.StatusAccepted, gin.H{"message": fmt.Sprintf("On-demand fetch started for region [%s]. Please try again later.", mkt)})
+		return
+	}
 	if err != nil {
 		sendImageNotFound(c, mkt)
 		return

internal/service/image/image_service.go

@@ -2,6 +2,7 @@ package image
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"time"
 
@@ -15,6 +16,8 @@ import (
 	"go.uber.org/zap"
 )
 
+var ErrFetchStarted = errors.New("on-demand fetch started")
+
 func CleanupOldImages(ctx context.Context) error {
 	days := config.GetConfig().Retention.Days
 	if days <= 0 {
@@ -60,14 +63,13 @@ func GetTodayImage(mkt string) (*model.Image, error) {
 	}
 	err := tx.Preload("Variants").First(&img).Error
 	if err != nil && mkt != "" && config.GetConfig().API.EnableOnDemandFetch && util.IsValidRegion(mkt) {
-		// 如果没找到，尝试按需抓取该地区
+		// 如果没找到，尝试异步按需抓取该地区
-		util.Logger.Info("Image not found in DB, attempting on-demand fetch", zap.String("mkt", mkt))
+		util.Logger.Info("Image not found in DB, starting asynchronous on-demand fetch", zap.String("mkt", mkt))
 		f := fetcher.NewFetcher()
+		go func() {
 			_ = f.FetchRegion(context.Background(), mkt)
-
+		}()
-		// 抓取后重新查询
+		return nil, ErrFetchStarted
-		tx = repo.DB.Where("date = ?", today).Where("mkt = ?", mkt)
-		err = tx.Preload("Variants").First(&img).Error
 	}
 
 	if err != nil {
@@ -118,14 +120,13 @@ func GetRandomImage(mkt string) (*model.Image, error) {
 	}
 	tx.Count(&count)
 	if count == 0 && mkt != "" && config.GetConfig().API.EnableOnDemandFetch && util.IsValidRegion(mkt) {
-		// 如果没找到，尝试按需抓取该地区
+		// 如果没找到，尝试异步按需抓取该地区
-		util.Logger.Info("No images found in DB for region, attempting on-demand fetch", zap.String("mkt", mkt))
+		util.Logger.Info("No images found in DB for region, starting asynchronous on-demand fetch", zap.String("mkt", mkt))
 		f := fetcher.NewFetcher()
+		go func() {
 			_ = f.FetchRegion(context.Background(), mkt)
-
+		}()
-		// 抓取后重新计数
+		return nil, ErrFetchStarted
-		tx = repo.DB.Model(&model.Image{}).Where("mkt = ?", mkt)
-		tx.Count(&count)
 	}
 
 	if count == 0 {
@@ -167,14 +168,13 @@ func GetImageByDate(date string, mkt string) (*model.Image, error) {
 	}
 	err := tx.Preload("Variants").First(&img).Error
 	if err != nil && mkt != "" && config.GetConfig().API.EnableOnDemandFetch && util.IsValidRegion(mkt) {
-		// 如果没找到，尝试按需抓取该地区
+		// 如果没找到，尝试异步按需抓取该地区
-		util.Logger.Info("Image not found in DB for date, attempting on-demand fetch", zap.String("mkt", mkt), zap.String("date", date))
+		util.Logger.Info("Image not found in DB for date, starting asynchronous on-demand fetch", zap.String("mkt", mkt), zap.String("date", date))
 		f := fetcher.NewFetcher()
+		go func() {
 			_ = f.FetchRegion(context.Background(), mkt)
-
+		}()
-		// 抓取后重新查询
+		return nil, ErrFetchStarted
-		tx = repo.DB.Where("date = ?", date).Where("mkt = ?", mkt)
-		err = tx.Preload("Variants").First(&img).Error
 	}
 
 	// 兜底逻辑

internal/util/regions.go

@@ -32,6 +32,4 @@ var AllRegions = []Region{
 	{Value: "ko-KR", Label: "韩国"},
 	{Value: "en-IN", Label: "印度"},
 	{Value: "ru-RU", Label: "俄罗斯"},
-	{Value: "zh-HK", Label: "中国香港"},
-	{Value: "zh-TW", Label: "中国台湾"},
 }