将原始图像数据转换为base64编码的字符串。

I am downloading a thumbnail from dropbox using the following API:

我正在使用以下API从dropbox下载缩略图:

https://www.dropbox.com/developers/documentation/http/documentation#files-get_thumbnail

https://www.dropbox.com/developers/documentation/http/documentation files-get_thumbnail

This is part of my function from cloud code:

这是我从云代码中得到的函数的一部分:

  }).then(function(oauthToken){
    /* Retrieve thumbnail image from dropbox */
    return Parse.Cloud.httpRequest({
      method: 'POST',
      url: 'https://content.dropboxapi.com/2/files/get_thumbnail',
      headers: {
        'Authorization': 'Bearer ' + oauthToken.get("accessToken"),
        'Dropbox-API-Arg': JSON.stringify({"path": dropboxFileId})
      }
    });

  }).then(function(imageResponse){
    if (log) {console.log(imageResponse);}
    var imageBuffer = imageResponse.buffer;
    var image = imageBuffer.toString("base64");
    response.success(image);
  }, function(error){
    response.error(error.text);
  });

Following is my imageResponse:

下面是我的imageResponse:

{ status: 200,
  headers: 
   { server: 'nginx',
     date: 'Wed, 16 Mar 2016 04:30:54 GMT',
     'content-type': 'application/octet-stream',
     'content-length': '906',
     connection: 'close',
     'accept-ranges': 'bytes',
     pragma: 'no-cache',
     'cache-control': 'no-cache',
     'original-content-length': '906',
     'dropbox-api-result': '{"name": "HTS-logo-low-res.png", "path_lower": "/hts-logo-low-res.png", "path_display": "/HTS-logo-low-res.png", "id": "id:hrkr_mV5FYAAAAAAAAAAHw", "client_modified": "2015-04-05T04:16:15Z", "server_modified": "2016-02-13T06:08:02Z", "rev": "2a043d0c726", "size": 10506}',
     'x-server-response-time': '190',
     'x-dropbox-request-id': '04bb8d6b45511f2b2d7a278e230ea572',
     'x-robots-tag': 'noindex, nofollow, noimageindex' },
  buffer: <Buffer ef bf bd ef bf bd ef bf bd ef bf bd 00 10 4a 46 49 46 00 01 01 00 00 01 00 01 00 00 ef bf bd ef bf bd 00 43 00 06 04 05 06 05 04 06 06 05 06 07 07 06 ... >,
  cookies: undefined,
  text: '����\u0000\u0010JFIF\u0000\u0001\u0001\u0000\u0000\u0001\u0000\u0001\u0000\u0000��\u0000C\u0000\u0006\u0004\u0005\u0006\u0005\u0004\u0006\u0006\u0005\u0006\u0007\u0007\u0006\b\n\u0010\n\n\t\t\n\u0014\u000e\u000f\f\u0010\u0017\u0014\u0018\u0018\u0017\u0014\u0016\u0016\u001a\u001d%\u001f\u001a\u001b#\u001c\u0016\u0016 , #&\')*)\u0019\u001f-0-(0%()(��\u0000C\u0001\u0007\u0007\u0007\n\b\n\u0013\n\n\u0013(\u001a\u0016\u001a((((((((((((((((((((((((((((((((((((((((((((((((((��\u0000\u0011\b\u0000\u0010\u0000@\u0003\u0001"\u0000\u0002\u0011\u0001\u0003\u0011\u0001��\u0000\u001f\u0000\u0000\u0001\u0005\u0001\u0001\u0001\u0001\u0001\u0001\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0001\u0002\u0003\u0004\u0005\u0006\u0007\b\t\n\u000b��\u0000�\u0010\u0000\u0002\u0001\u0003\u0003\u0002\u0004\u0003\u0005\u0005\u0004\u0004\u0000\u0000\u0001}\u0001\u0002\u0003\u0000\u0004\u0011\u0005\u0012!1A\u0006\u0013Qa\u0007"q\u00142���\b#B��\u0015R��$3br�\t\n\u0016\u0017\u0018\u0019\u001a%&\'()*456789:CDEFGHIJSTUVWXYZcdefghijstuvwxyz���������������������������������������������������������������������������\u0000\u001f\u0001\u0000\u0003\u0001\u0001\u0001\u0001\u0001\u0001\u0001\u0001\u0001\u0000\u0000\u0000\u0000\u0000\u0000\u0001\u0002\u0003\u0004\u0005\u0006\u0007\b\t\n\u000b��\u0000�\u0011\u0000\u0002\u0001\u0002\u0004\u0004\u0003\u0004\u0007\u0005\u0004\u0004\u0000\u0001\u0002w\u0000\u0001\u0002\u0003\u0011\u0004\u0005!1\u0006\u0012AQ\u0007aq\u0013"2�\b\u0014B����\t#3R�\u0015br�\n\u0016$4�%�\u0017\u0018\u0019\u001a&\'()*56789:CDEFGHIJSTUVWXYZcdefghijstuvwxyz��������������������������������������������������������������������������\u0000\f\u0003\u0001\u0000\u0002\u0011\u0003\u0011\u0000?\u0000�;ŷ��鱘\'[s,�\u0013L�\n���{\f�g޹\u000f��I�\\.�w\u0013��H~̡���\u0002�\u001b���\u000f\u0001���@�%�&�O��\u0004z����6�Z:X�"G;�GB}M%N�3��ͧ]4��̪��9`�������0�֕�+\u000b�t \u0006P�\u0001%�z��\u0003�R=ި�G$.� �U��h]���d�\u001d9����u���*O����q��|�\u0007\u0005\\�N\u000e\u0017\u0003�\u0000C�q��;�K���1\u001e��HR��z��~�N+���uy��d�بS咕�0e��91�\u001fC�\u0014���}z����.u\u0019Y�I\u0012�T.�\u0019~�\u0007ߦ\b��+���ߝ��W���_q��'
}

My code in XCode:

我的代码在XCode中:

if let imageInBase64 = response as? String {
    print(imageInBase64)
    let decodedImage = NSData(base64EncodedString: imageInBase64, options: NSDataBase64DecodingOptions())
    imageView.image = UIImage(data: decodedImage!)
}

Following is the output for imageInBase64:

以下是imageInBase64的输出:

77+977+977+977+9ABBKRklGAAEBAAABAAEAAO+/ve+/vQBDAAYEBQYFBAYGBQYHBwYIChAKCgkJChQODwwQFxQYGBcUFhYaHSUfGhsjHBYWICwgIyYnKSopGR8tMC0oMCUoKSjvv73vv70AQwEHBwcKCAoTCgoTKBoWGigoKCgoKCgoKCgoKCgoKCgoKCgoKCgoKCgoKCgoKCgoKCgoKCgoKCgoKCgoKCgoKCgo77+977+9ABEIABAAQAMBIgACEQEDEQHvv73vv70AHwAAAQUBAQEBAQEAAAAAAAAAAAECAwQFBgcICQoL77+977+9AO+/vRAAAgEDAwIEAwUFBAQAAAF9AQIDAAQRBRIhMUEGE1FhByJxFDLvv73vv73vv70II0Lvv73vv70VUu+/ve+/vSQzYnLvv70JChYXGBkaJSYnKCkqNDU2Nzg5OkNERUZHSElKU1RVVldYWVpjZGVmZ2hpanN0dXZ3eHl677+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+977+9AB8BAAMBAQEBAQEBAQEAAAAAAAABAgMEBQYHCAkKC++/ve+/vQDvv70RAAIBAgQEAwQHBQQEAAECdwABAgMRBAUhMQYSQVEHYXETIjLvv70IFELvv73vv73vv73vv70JIzNS77+9FWJy77+9ChYkNO+/vSXvv70XGBkaJicoKSo1Njc4OTpDREVGR0hJSlNUVVZXWFlaY2RlZmdoaWpzdHV2d3h5eu+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/ve+/vQAMAwEAAhEDEQA/AO+/vTvFt++/ve+/vemxmCdbcyzvv70TTO+/vQrvv73vv73vv717DO+/vWfeuX8P77+977+9Se+/vVwu77+9dxPvv73vv71Ifsyh77+977+977+9Au+/vRvvv73vv73vv70PAe+/ve+/ve+/vUDvv70l77+9Ju+/vU/vv73vv70Eeu+/ve+/ve+/ve+/vTbvv71aOljvv70iRzvvv71HQn1NJU7vv70z77+977+9zaddNO+/ve+/vcyq77+977+9OWDvv73vv73vv73vv73vv73vv73vv70w77+91pXvv70rC++/vXQgBlDvv70BJe+/vXrvv73vv70D77+9Uj3eqO+/vUckLu+/vSDvv71V77+977+9aF3vv73vv73vv71k77+9HTnvv73vv73vv73vv71177+977+977+9Kk/vv73vv73vv73vv71x77+977+9fO+/vQcFXO+/vU4OFwPvv70AQ++/vXHvv73vv70777+9S++/ve+/ve+/vTEe77+977+9SFLvv73vv71677+977+9fu+/vU4r77+977+977+9dXnvv73vv71k77+92KhT5ZKV77+9MGXvv73vv705Me+/vR9D77+9FO+/ve+/ve+/vX1677+977+977+977+9LnUZWe+/vUkS77+9VC7vv70Zfu+/vQffpgjvv73vv70r77+977+977+9353vv73vv71X77+977+977+9X3Hvv73vv70=

When I run this, I do not get an image displayed. I suspect that I am not properly handling the response from Dropbox before converting it to base64 string. Dropbox state that their responses are raw image data.

当我运行这个时，我没有显示图像。我怀疑在将其转换为base64字符串之前，我没有正确处理Dropbox的响应。Dropbox声明他们的回应是原始图像数据。

Any help will be much appreciated. Thanks.

非常感谢您的帮助。谢谢。

1 个解决方案

#1

Figured it out & thanks for those who answered. The issue was with Parse.com module Parse.Cloud.httpRequest which works slightly different when you are self-hosting parse-server vs Parse.com. I just needed to include encoding: null as an option in the module and everything works fine. Code below:

找出答案，并感谢那些回答的人。问题是Parse.com模块Parse.Cloud。当您是自托管parse-server vs Parse.com时，httpRequest的工作方式略有不同。我只需要将编码包括:null作为模块中的一个选项，一切正常。下面的代码:

  }).then(function(oauthToken){
    /* Retrieve thumbnail image from dropbox */
    return Parse.Cloud.httpRequest({
      method: 'POST',
      url: 'https://content.dropboxapi.com/2/files/get_thumbnail',
      headers: {
        'Authorization': 'Bearer ' + oauthToken.get("accessToken"),
        'Dropbox-API-Arg': JSON.stringify({"path": dropboxFileId})
      },
      encoding: null
    });

  }).then(function(imageResponse){
    if (log) {console.log(imageResponse);}
    var imageBuffer = imageResponse.buffer;
    var image = imageBuffer.toString("base64");
    response.success(image);
  }, function(error){
    response.error(error.text);
  });