feat: scaffold files service

internal/storage/minio.go

@@ -0,0 +1,183 @@
+package storage
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"io"
+	"mime"
+	"net/http"
+	"path/filepath"
+	"strconv"
+	"strings"
+
+	"github.com/google/uuid"
+	"github.com/minio/minio-go/v7"
+	"github.com/minio/minio-go/v7/pkg/credentials"
+)
+
+type Config struct {
+	Endpoint  string
+	AccessKey string
+	SecretKey string
+	Bucket    string
+	UseSSL    bool
+}
+
+type Storage struct {
+	cfg    Config
+	client *minio.Client
+}
+
+type ObjectInfo struct {
+	Size        int64
+	ContentType string
+}
+
+func New(cfg Config) (*Storage, error) {
+	if cfg.Endpoint == "" || cfg.AccessKey == "" || cfg.SecretKey == "" {
+		return &Storage{cfg: cfg}, nil
+	}
+	cli, err := minio.New(cfg.Endpoint, &minio.Options{
+		Creds:  credentials.NewStaticV4(cfg.AccessKey, cfg.SecretKey, ""),
+		Secure: cfg.UseSSL,
+	})
+	if err != nil {
+		return nil, fmt.Errorf("init minio client: %w", err)
+	}
+	return &Storage{cfg: cfg, client: cli}, nil
+}
+
+func (s *Storage) Configured() bool {
+	return s.client != nil && s.cfg.Bucket != ""
+}
+
+func (s *Storage) EnsureBucket(ctx context.Context) error {
+	if !s.Configured() {
+		return nil
+	}
+	exists, err := s.client.BucketExists(ctx, s.cfg.Bucket)
+	if err != nil {
+		return fmt.Errorf("check bucket: %w", err)
+	}
+	if exists {
+		return nil
+	}
+	return s.client.MakeBucket(ctx, s.cfg.Bucket, minio.MakeBucketOptions{})
+}
+
+func GenerateKey(ownerID, filename string) string {
+	ext := strings.ToLower(strings.TrimPrefix(filepath.Ext(filename), "."))
+	if !AllowedExtension(ext) {
+		ext = "bin"
+	}
+	return fmt.Sprintf("%s/%s.%s", ownerID, uuid.NewString(), ext)
+}
+
+func AllowedExtension(ext string) bool {
+	switch strings.ToLower(ext) {
+	case "doc", "docx", "xls", "xlsx", "xlsm", "ppt", "pptx", "ods", "odt", "odp",
+		"pdf", "png", "jpg", "jpeg", "webp", "gif", "mp4", "webm", "mov", "m4v", "mp3", "wav", "ogg":
+		return true
+	default:
+		return false
+	}
+}
+
+func GuessContentType(filename, clientType string) string {
+	if clientType != "" && clientType != "application/octet-stream" {
+		return clientType
+	}
+	if ext := filepath.Ext(filename); ext != "" {
+		if v := mime.TypeByExtension(ext); v != "" {
+			return v
+		}
+	}
+	return "application/octet-stream"
+}
+
+func (s *Storage) PutObject(ctx context.Context, key string, body io.Reader, size int64, contentType string) error {
+	if !s.Configured() {
+		return errors.New("storage not configured")
+	}
+	_, err := s.client.PutObject(ctx, s.cfg.Bucket, key, body, size, minio.PutObjectOptions{
+		ContentType: contentType,
+	})
+	return err
+}
+
+func (s *Storage) Stat(ctx context.Context, key string) (*ObjectInfo, error) {
+	if !s.Configured() {
+		return nil, errors.New("storage not configured")
+	}
+	info, err := s.client.StatObject(ctx, s.cfg.Bucket, key, minio.StatObjectOptions{})
+	if err != nil {
+		return nil, err
+	}
+	return &ObjectInfo{Size: info.Size, ContentType: info.ContentType}, nil
+}
+
+func (s *Storage) GetObject(ctx context.Context, key string, rangeStart, rangeEnd int64) (io.ReadCloser, *ObjectInfo, error) {
+	if !s.Configured() {
+		return nil, nil, errors.New("storage not configured")
+	}
+	opts := minio.GetObjectOptions{}
+	if rangeStart > 0 || rangeEnd > 0 {
+		_ = opts.SetRange(rangeStart, rangeEnd)
+	}
+	obj, err := s.client.GetObject(ctx, s.cfg.Bucket, key, opts)
+	if err != nil {
+		return nil, nil, err
+	}
+	info, err := obj.Stat()
+	if err != nil {
+		_ = obj.Close()
+		return nil, nil, err
+	}
+	return obj, &ObjectInfo{Size: info.Size, ContentType: info.ContentType}, nil
+}
+
+func ParseRange(header string, totalSize int64) (start, end int64, ok bool) {
+	if !strings.HasPrefix(header, "bytes=") {
+		return 0, 0, false
+	}
+	parts := strings.SplitN(strings.TrimPrefix(header, "bytes="), "-", 2)
+	if len(parts) != 2 {
+		return 0, 0, false
+	}
+	if parts[0] == "" {
+		n, err := strconv.ParseInt(parts[1], 10, 64)
+		if err != nil || n <= 0 || n > totalSize {
+			return 0, 0, false
+		}
+		return totalSize - n, totalSize - 1, true
+	}
+	start, err := strconv.ParseInt(parts[0], 10, 64)
+	if err != nil || start < 0 || start >= totalSize {
+		return 0, 0, false
+	}
+	if parts[1] == "" {
+		return start, totalSize - 1, true
+	}
+	end, err = strconv.ParseInt(parts[1], 10, 64)
+	if err != nil || end < start {
+		return 0, 0, false
+	}
+	if end >= totalSize {
+		end = totalSize - 1
+	}
+	return start, end, true
+}
+
+func WriteRangeResponse(w http.ResponseWriter, contentType string, totalSize, start, end int64, hasRange bool) {
+	w.Header().Set("Content-Type", contentType)
+	w.Header().Set("Accept-Ranges", "bytes")
+	if hasRange {
+		w.Header().Set("Content-Range", fmt.Sprintf("bytes %d-%d/%d", start, end, totalSize))
+		w.Header().Set("Content-Length", strconv.FormatInt(end-start+1, 10))
+		w.WriteHeader(http.StatusPartialContent)
+		return
+	}
+	w.Header().Set("Content-Length", strconv.FormatInt(totalSize, 10))
+	w.WriteHeader(http.StatusOK)
+}