feat: add file upload workflow

backend/internal/modules/file/storage.go

@@ -0,0 +1,122 @@
+package file
+
+import (
+	"context"
+	"crypto/rand"
+	"encoding/hex"
+	"fmt"
+	"io"
+	"mime/multipart"
+	"net/url"
+	"path"
+	"strings"
+	"time"
+
+	"hfb_sys/backend/internal/config"
+
+	"github.com/minio/minio-go/v7"
+	"github.com/minio/minio-go/v7/pkg/credentials"
+)
+
+type Storage struct {
+	client *minio.Client
+	bucket string
+}
+
+type Object struct {
+	Reader      io.ReadCloser
+	ContentType string
+	Size        int64
+}
+
+func NewStorage(cfg config.StorageConfig) (*Storage, error) {
+	endpoint, secure, err := normalizeEndpoint(cfg.Endpoint)
+	if err != nil {
+		return nil, err
+	}
+	client, err := minio.New(endpoint, &minio.Options{
+		Creds:  credentials.NewStaticV4(cfg.AccessKeyID, cfg.SecretAccessKey, ""),
+		Secure: secure,
+	})
+	if err != nil {
+		return nil, err
+	}
+	storage := &Storage{client: client, bucket: cfg.Bucket}
+	if err := storage.ensureBucket(context.Background()); err != nil {
+		return nil, err
+	}
+	return storage, nil
+}
+
+func (s *Storage) Put(ctx context.Context, scene string, header *multipart.FileHeader, reader io.Reader, contentType string) (string, error) {
+	key, err := newObjectKey(scene, header.Filename)
+	if err != nil {
+		return "", err
+	}
+	_, err = s.client.PutObject(ctx, s.bucket, key, reader, header.Size, minio.PutObjectOptions{
+		ContentType: contentType,
+		UserMetadata: map[string]string{
+			"original-filename": header.Filename,
+		},
+	})
+	if err != nil {
+		return "", err
+	}
+	return key, nil
+}
+
+func (s *Storage) Get(ctx context.Context, key string) (*Object, error) {
+	object, err := s.client.GetObject(ctx, s.bucket, key, minio.GetObjectOptions{})
+	if err != nil {
+		return nil, err
+	}
+	info, err := object.Stat()
+	if err != nil {
+		_ = object.Close()
+		return nil, err
+	}
+	return &Object{
+		Reader:      object,
+		ContentType: info.ContentType,
+		Size:        info.Size,
+	}, nil
+}
+
+func (s *Storage) ensureBucket(ctx context.Context) error {
+	exists, err := s.client.BucketExists(ctx, s.bucket)
+	if err != nil {
+		errResp := minio.ToErrorResponse(err)
+		if errResp.Code != "NoSuchBucket" && !strings.Contains(strings.ToLower(err.Error()), "bucket does not exist") {
+			return err
+		}
+	}
+	if exists {
+		return nil
+	}
+	return s.client.MakeBucket(ctx, s.bucket, minio.MakeBucketOptions{})
+}
+
+func normalizeEndpoint(raw string) (string, bool, error) {
+	parsed, err := url.Parse(raw)
+	if err != nil {
+		return "", false, err
+	}
+	if parsed.Scheme == "" {
+		return raw, false, nil
+	}
+	return parsed.Host, parsed.Scheme == "https", nil
+}
+
+func newObjectKey(scene string, filename string) (string, error) {
+	if scene == "" {
+		scene = "misc"
+	}
+	scene = strings.ToLower(scene)
+	now := time.Now()
+	token := make([]byte, 12)
+	if _, err := rand.Read(token); err != nil {
+		return "", err
+	}
+	ext := strings.ToLower(path.Ext(filename))
+	return fmt.Sprintf("%s/%04d/%02d/%02d/%s%s", scene, now.Year(), now.Month(), now.Day(), hex.EncodeToString(token), ext), nil
+}