You might see that the Dropbox Community team have been busy working on some major updates to the Community itself! So, here is some info on what’s changed, what’s staying the same and what you can expect from the Dropbox Community overall.

Forum Discussion

De L.1's avatar
De L.1
Collaborator | Level 9
2 years ago

Downloading part of a file via /get_temporary_link with Range header returns incorrect content-type

When downloading a specific part of a file using the link received via a /get_temporary_link call and the HTTP header Range: bytes=..., the content-type application/grpc is sent instead of the actual content-type of the file.

 

Request Headers:

 

GET https://uc383828c22b...3d5ecbc28.dl.dropboxusercontent.com/cd/0/get/B61A....17HuE3Lr3UI4EEpPY/file
range:bytes=0-

 


Expected Response Headers:

 

HTTP/1.1 206 Partial Content
---
accept-ranges:bytes
Content-Length:26397831
Content-Range:bytes 0-26397830/26397831
content-type:video/mp4

 

 

Actual Response Headers:

 

HTTP/1.1 206 Partial Content
---
accept-ranges:bytes
Content-Length:26397831
Content-Range:bytes 0-26397830/26397831
content-type:application/grpc

 

 

So in this example (actually downloading the full file, but with the Range header), the video file is downloaded with a content-type of application/grpc rather than video/mp4.

 

This causes problems when (for example) you want to display a video file in an HTML 5 player using the link received from the /get_temporary_link call.  The HTML 5 player buffers the video file and loads the data in chunks. However, due to the incorrect content type, the browser will not accept the data as video content and will not be able to play it.

I've just noticed this problem, and I didn't have any problems with it before. So I think this problem has been introduced recently?

  • This should be fixed now. Please let us know if you're still seeing any issues.

  • ncw's avatar
    ncw
    Collaborator | Level 8

    Rclone users have reported a similar problem when using anything with `Range:` requests.

     

    There is a long thread here https://forum.rclone.org/t/failed-to-open-source-not-an-encrypted-file-bad-magic-string/37790

     

    But my summary is that Range: requests are not working properly. They appear to produce files which have an extra bit of HTTP header in them such as this (from the link above)

     

    I noticed "application/octet-stream" inside my all files header.
    Because of that, my applications do not recigionize files as valid.

    0000000 000 000 002 000 042 012 236 200 010 012 030 141 160 160 154 151
             \0  \0 002  \0   "  \n 236 200  \b  \n 030   a   p   p   l   i
    0000020 143 141 164 151 157 156 057 157 143 164 145 164 055 163 164 162
              c   a   t   i   o   n   /   o   c   t   e   t   -   s   t   r
    0000040 145 141 155 022 200 200 010 120 162 157 157 146 040 157 146 040
              e   a   m 022 200 200  \b
    

     

    This looks like a Dropbox bug to me.

     

     
     
    • ncw's avatar
      ncw
      Collaborator | Level 8

      Here is a failing request and response

       

      I managed to reproduce this with a small file file.txt contents shello and using

      rclone cat --offset 3 dropbox:file.txt -vv --dump bodies

      This made this request

      2023/04/25 11:20:46 DEBUG : HTTP REQUEST (req 0xc0009fec00)
      2023/04/25 11:20:46 DEBUG : POST /2/files/download HTTP/1.1
      Host: content.dropboxapi.com
      User-Agent: rclone/v1.63.0-beta.6980.470db6bcd
      Content-Length: 0
      Authorization: XXXX
      Content-Type: application/octet-stream
      Dropbox-Api-Arg: {"path":"id:qqS0afUHwS0AAAAAAA6Nig"}
      Range: bytes=3-6
      
      

      And this response which appears to have muddled up the body with the header

      2023/04/25 11:20:47 DEBUG : HTTP RESPONSE (req 0xc0009fec00)
      2023/04/25 11:20:47 Unsolicited response received on idle HTTP channel starting with "\"\n \n\x18application/octet-stream\x12\x04llo\n"; err=<nil>
      2023/04/25 11:20:47 DEBUG : HTTP/1.1 206 Partial Content
      Content-Length: 4
      Accept-Encoding: identity,gzip
      Accept-Ranges: bytes
      Content-Range: bytes 3-6/7
      Content-Security-Policy: sandbox allow-forms allow-scripts
      Content-Type: application/grpc
      Date: Tue, 25 Apr 2023 10:20:46 GMT
      Dropbox-Api-Result: {"name": "file.txt", "path_lower": "/file.txt", "path_display": "/file.txt", "id": "id:qqS0afUHwS0AAAAAAA6Nig", "client_modified": "2022-11-09T12:59:37Z", "server_modified": "2022-11-09T12:59:41Z", "rev": "5ed093ae1400f082af73a", "size": 7, "is_downloadable": true, "content_hash": "483068e5287bde73b67923dae8c200d461d80997108030841a082e628489993b"}
      Etag: W/"5ed093ae1400f082af73a"
      Original-Content-Length: 4
      Server: envoy
      Strict-Transport-Security: max-age=31536000; includeSubDomains; preload
      X-Dropbox-Request-Id: e186d6db20684aee82e1123611632a3a
      X-Dropbox-Response-Origin: far_remote
      X-Robots-Tag: noindex, nofollow, noimageindex
      
      
       
       
      • Greg-DB's avatar
        Greg-DB
        Icon for Dropbox Staff rankDropbox Staff

        Thanks for the report! We're looking into it. I'll follow up here once I have an update on this.

About Dropbox API Support & Feedback

Node avatar for Dropbox API Support & Feedback

Find help with the Dropbox API from other developers.

5,882 PostsLatest Activity: 3 years ago
325 Following

If you need more help you can view your support options (expected response time for an email or ticket is 24 hours), or contact us on X or Facebook.

For more info on available support options for your Dropbox plan, see this article.

If you found the answer to your question in this Community thread, please 'like' the post to say thanks and to let us know it was useful!