file: add taskqueue worker process image thumbnail

file/worker/imageprocessworker.go

@@ -0,0 +1,196 @@
+package worker
+
+import (
+	"bytes"
+	"context"
+	"errors"
+	"fmt"
+	"godemo/file/file"
+	"godemo/file/internal/svc"
+	"image"
+	"image/jpeg"
+	_ "image/png"
+	"io"
+	"strings"
+	"time"
+
+	"github.com/minio/minio-go/v7"
+	"github.com/zeromicro/go-zero/core/logx"
+)
+
+// 图片处理任务
+type ImageProcessTask struct {
+	FileID    string              // 原始文件ID
+	Versions  []file.ImageVersion // 需要生成的版本
+	RequestID string              // 请求ID（用于追踪）
+	CreatedAt time.Time           // 创建时间
+}
+
+var ImageProcessTaskQueue chan ImageProcessTask
+
+func InitImageProcessTaskQueue(bufferSize int) {
+	ImageProcessTaskQueue = make(chan ImageProcessTask, bufferSize)
+}
+
+func StartImageProcessWorkers(workerCount int, svcCtx *svc.ServiceContext) {
+	for i := 0; i < workerCount; i++ {
+		go func(workerID int) {
+			for task := range ImageProcessTaskQueue {
+				logx.Infof("Worker %d processing task for FileID: %s", workerID, task.FileID)
+				if err := processImage(task, svcCtx); err != nil {
+					logx.Errorf("Worker %d failed to process FileID: %s, err: %v", workerID, task.FileID, err)
+				}
+			}
+		}(i)
+	}
+}
+
+func processImage(task ImageProcessTask, svcCtx *svc.ServiceContext) error {
+	// 加载原始图片（示意，假设你实现了这类方法）
+	originalImage, err := LoadImageFromMinIO(svcCtx.MinioClient, task.FileID, file.ImageVersion_original)
+	if err != nil {
+		return err
+	}
+
+	// 如果是 ALL，则转化成 THUMBNAIL + PREVIEW
+	versions := task.Versions
+	if len(versions) == 1 && versions[0] == file.ImageVersion_all {
+		versions = []file.ImageVersion{file.ImageVersion_thumbnail, file.ImageVersion_preview}
+	}
+
+	for _, version := range versions {
+		switch version {
+		case file.ImageVersion_thumbnail:
+			err := generateAndUpload(originalImage, task.FileID, file.ImageVersion_thumbnail, svcCtx)
+			if err != nil {
+				logx.Errorf("Generate thumbnail failed: %v", err)
+			}
+		case file.ImageVersion_preview:
+			err := generateAndUpload(originalImage, task.FileID, file.ImageVersion_preview, svcCtx)
+			if err != nil {
+				logx.Errorf("Generate preview failed: %v", err)
+			}
+		default:
+			logx.Infof("Unsupported image version: %v", version)
+		}
+	}
+
+	return nil
+}
+
+func generateAndUpload(originalImage []byte, fileID string, version file.ImageVersion, svcCtx *svc.ServiceContext) error {
+	// 示例尺寸（你可以从配置或常量读取）
+	var width, height int
+	switch version {
+	case file.ImageVersion_thumbnail:
+		width, height = 150, 150
+	case file.ImageVersion_preview:
+		width, height = 800, 600
+	}
+
+	// resize（伪代码：请换成你自己的图像处理库，如 imaging）
+	resizedImage, err := ResizeImage(originalImage, width, height)
+	if err != nil {
+		logx.Errorf("generateAndUpload failed: %v", err)
+		return err
+	}
+
+	// 上传到 MinIO
+	return UploadImageToMinIO(svcCtx.MinioClient, fileID, version, resizedImage)
+}
+
+func LoadImageFromMinIO(client *minio.Client, fileID string, version file.ImageVersion) ([]byte, error) {
+	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+	defer cancel()
+
+	bucket, objectKey, _ := GetBucketAndObjectKey(fileID, version)
+
+	object, err := client.GetObject(ctx, bucket, objectKey, minio.GetObjectOptions{})
+	if err != nil {
+		return nil, fmt.Errorf("failed to get object from MinIO: %w", err)
+	}
+	defer object.Close()
+
+	buf := new(bytes.Buffer)
+	if _, err := io.Copy(buf, object); err != nil {
+		return nil, fmt.Errorf("failed to read object: %w", err)
+	}
+
+	return buf.Bytes(), nil
+}
+
+func GetBucketAndObjectKey(fileId string, version file.ImageVersion) (string, string, error) {
+	bucket := version.String()
+	objectKey := fileId
+	if version == file.ImageVersion_original {
+		// fileID = xx/yy/cc/ll.png 获取第一段作为bucket
+		bucket, objectKey, _ = GetBucketAndObjectKeyFromFileID(fileId)
+	}
+	return bucket, objectKey, nil
+}
+
+func GetBucketAndObjectKeyFromFileID(fileID string) (string, string, error) {
+	idx := strings.Index(fileID, "/")
+	if idx == -1 {
+		return "", "", fmt.Errorf("invalid fileID: %s", fileID)
+	}
+	return fileID[:idx], fileID[idx+1:], nil
+}
+
+func ResizeImage(original []byte, width, height int) ([]byte, error) {
+	img, _, err := image.Decode(bytes.NewReader(original))
+	if err != nil {
+		logx.Errorf("ResizeImage failed: %v", err)
+		return nil, err
+	}
+
+	srcBounds := img.Bounds()
+	srcWidth := srcBounds.Dx()
+	srcHeight := srcBounds.Dy()
+
+	if srcWidth == 0 || srcHeight == 0 {
+		return nil, errors.New("source image has zero size")
+	}
+
+	// 创建缩放后的图像（RGBA 格式）
+	dst := image.NewRGBA(image.Rect(0, 0, width, height))
+
+	// 最近邻缩放
+	for y := 0; y < height; y++ {
+		for x := 0; x < width; x++ {
+			srcX := x * srcWidth / width
+			srcY := y * srcHeight / height
+			color := img.At(srcX+srcBounds.Min.X, srcY+srcBounds.Min.Y)
+			dst.Set(x, y, color)
+		}
+	}
+
+	// 编码为 JPEG
+	var buf bytes.Buffer
+	err = jpeg.Encode(&buf, dst, &jpeg.Options{Quality: 85})
+	if err != nil {
+		return nil, err
+	}
+
+	return buf.Bytes(), nil
+}
+
+func UploadImageToMinIO(client *minio.Client, fileID string, version file.ImageVersion, data []byte) error {
+	bucket, objectKey, err := GetBucketAndObjectKey(fileID, version)
+	if err != nil {
+		return err
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+	defer cancel()
+
+	_, err = client.PutObject(ctx, bucket, objectKey, bytes.NewReader(data), int64(len(data)), minio.PutObjectOptions{
+		ContentType: "image/jpeg",
+	})
+	logx.Infof("Uploaded image to MinIO: %s/%s", bucket, objectKey)
+	if err != nil {
+		return fmt.Errorf("upload to MinIO failed: %w", err)
+	}
+
+	return nil
+}