Class S3Backend

packages/core/src/sync/s3-backend.ts:157–518

}

export class S3Backend implements ISyncBackend {
  readonly type = "s3" as const;
  private client: S3Client;
  private config: S3Config;
  private remoteRoot: string;

  constructor(config: S3Config, secretAccessKey: string) {
    this.remoteRoot =
      sanitizeS3RemoteRoot(config.remoteRoot ?? DEFAULT_S3_REMOTE_ROOT) || DEFAULT_S3_REMOTE_ROOT;
    this.config = {
      ...config,
      remoteRoot: this.remoteRoot,
    };
    let requestHandler: PlatformFetchHttpHandler | undefined;
    try {
      const platform = getPlatformService();
      if (platform.isDesktop) {
        requestHandler = new PlatformFetchHttpHandler();
      }
    } catch {
      // Platform service may not be initialized in tests that never touch S3.
    }

    // Auto-detect path-style for non-AWS endpoints. Self-hosted S3-compatible
    // servers (rclone serve s3, MinIO, IP/localhost endpoints) overwhelmingly
    // require path-style addressing because their hostname can't carry the
    // bucket as a subdomain. AWS S3 supports both styles, so leave that alone.
    // Users can still override via the UI toggle.
    const pathStyle = config.pathStyle ?? shouldDefaultToPathStyle(config.endpoint);

    const clientConfig = {
      endpoint: config.endpoint,
      region: config.region,
      credentials: {
        accessKeyId: config.accessKeyId,
        secretAccessKey,
      },
      forcePathStyle: pathStyle,
      ...(requestHandler ? { requestHandler } : {}),
    };

    this.client = new S3Client(clientConfig);
  }

  async testConnection(): Promise<boolean> {
    try {
      await this.client.send(
        new ListObjectsV2Command({
          Bucket: this.config.bucket,
          MaxKeys: 1,
          Prefix: `${this.remoteRoot}/`,
        }),
      );
      return true;
    } catch (error) {
      // The SDK's Error subclasses don't serialize their useful fields via
      // default console.error formatting, so the feedback log capture ends
      // up with just "Error: ..." and the user can't tell what went wrong.