first commit

apps/backend/internal/filestorage/s3.go

@@ -0,0 +1,126 @@
+package filestorage
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"io"
+	"os"
+	"strconv"
+	"strings"
+
+	"github.com/aws/aws-sdk-go-v2/aws"
+	"github.com/aws/aws-sdk-go-v2/credentials"
+	"github.com/aws/aws-sdk-go-v2/service/s3"
+	"github.com/aws/aws-sdk-go-v2/service/s3/types"
+	"github.com/aws/smithy-go"
+)
+
+type S3Storage struct {
+	client *s3.Client
+	bucket string
+}
+
+func NewS3FromEnv() (*S3Storage, error) {
+	bucket := strings.TrimSpace(os.Getenv("S3_BUCKET"))
+	accessKey := strings.TrimSpace(os.Getenv("S3_ACCESS_KEY"))
+	secretKey := strings.TrimSpace(os.Getenv("S3_SECRET_KEY"))
+	if bucket == "" || accessKey == "" || secretKey == "" {
+		return nil, errors.New("S3_BUCKET, S3_ACCESS_KEY, and S3_SECRET_KEY are required for FILE_STORAGE_PROVIDER=s3")
+	}
+
+	region := strings.TrimSpace(os.Getenv("S3_REGION"))
+	if region == "" {
+		region = "us-east-1"
+	}
+	endpoint := strings.TrimSpace(os.Getenv("S3_ENDPOINT"))
+	usePathStyle, _ := strconv.ParseBool(strings.TrimSpace(os.Getenv("S3_USE_PATH_STYLE")))
+
+	cfg := aws.Config{
+		Region:      region,
+		Credentials: aws.NewCredentialsCache(credentials.NewStaticCredentialsProvider(accessKey, secretKey, "")),
+	}
+	client := s3.NewFromConfig(cfg, func(options *s3.Options) {
+		options.UsePathStyle = usePathStyle
+		if endpoint != "" {
+			options.BaseEndpoint = aws.String(endpoint)
+		}
+	})
+	return &S3Storage{client: client, bucket: bucket}, nil
+}
+
+func (s *S3Storage) Provider() string {
+	return "s3"
+}
+
+func (s *S3Storage) Probe(ctx context.Context) error {
+	_, err := s.client.HeadBucket(ctx, &s3.HeadBucketInput{Bucket: aws.String(s.bucket)})
+	return err
+}
+
+func (s *S3Storage) Put(ctx context.Context, key string, reader io.Reader, contentType string, size int64) error {
+	_, err := s.client.PutObject(ctx, &s3.PutObjectInput{
+		Bucket:        aws.String(s.bucket),
+		Key:           aws.String(key),
+		Body:          reader,
+		ContentType:   aws.String(contentType),
+		ContentLength: aws.Int64(size),
+	})
+	return err
+}
+
+func (s *S3Storage) Get(ctx context.Context, key string) (Object, error) {
+	response, err := s.client.GetObject(ctx, &s3.GetObjectInput{
+		Bucket: aws.String(s.bucket),
+		Key:    aws.String(key),
+	})
+	if err != nil {
+		if isS3NotFoundError(err) {
+			return Object{}, ErrNotFound
+		}
+		return Object{}, err
+	}
+
+	contentType := ""
+	if response.ContentType != nil {
+		contentType = *response.ContentType
+	}
+	size := int64(0)
+	if response.ContentLength != nil {
+		size = *response.ContentLength
+	}
+	return Object{
+		Body:        response.Body,
+		ContentType: contentType,
+		Size:        size,
+	}, nil
+}
+
+func (s *S3Storage) Delete(ctx context.Context, key string) error {
+	_, err := s.client.DeleteObject(ctx, &s3.DeleteObjectInput{
+		Bucket: aws.String(s.bucket),
+		Key:    aws.String(key),
+	})
+	if err != nil {
+		if isS3NotFoundError(err) {
+			return nil
+		}
+		return fmt.Errorf("delete s3 object: %w", err)
+	}
+	return nil
+}
+
+func isS3NotFoundError(err error) bool {
+	var noSuchKey *types.NoSuchKey
+	if errors.As(err, &noSuchKey) {
+		return true
+	}
+	var apiErr smithy.APIError
+	if errors.As(err, &apiErr) {
+		switch apiErr.ErrorCode() {
+		case "NoSuchKey", "NotFound", "NoSuchBucket":
+			return true
+		}
+	}
+	return false
+}