图片上传和预览服务 上传api: http --multipart POST localhost:9000/upload bucket=b1 file_name@/Downloads/1.jpeg 预览api: http://localhost:9000/preview/b1/06f53cce7fec99ce242a85275285a2d3.jpeg 格式: {base_url}/{bucket}/{image_name} image_upload_server image_upload_server