file transfer improvements

[Antoine Martin]

Split from #494, remaining tasks:

• each file needs to be chunked so we can interleave regular xpra traffic - high priority
• ability to cancel transfers in progress
• client option of showing a dialog to accept files before starting the transfer (and choose download location?)

[J. Max Mena]

Edit: comment about a file too big error moved to ticket:494#comment:6

We should probably also handle the file-too-big issue with an alert box?

[Antoine Martin]

Also from ticket:494#comment:8 : GtkWarning: Could not find the icon 'gtk-file'. The 'hicolor' theme was not found either, perhaps you need to install it
Looks like we may need to tweak the win32 packaging to include or point to the (more complete?) theme.

[Antoine Martin]

#1124 is a nicer, more generic solution to this problem.

[Antoine Martin]

refactoring needed to add chunking code only in one place

[Antoine Martin]

mostly complete patch, just needs cleaning up and cancelling the timers

[Antoine Martin]

Done: preparatory refactoring in r12810 + r12812, actual chunking code in r12813.

The files are now sent in chunks. We wait for the file chunk ack packet before sending the next chunk, which helps to ensure that we don't use up all the bandwidth, though it does reduce the throughput (only 4MB/s on a powerfull system loopback).

New tunables which should be self-explanatory:

XPRA_FILE_CHUNKS_SIZE=65536
XPRA_MAX_CONCURRENT_FILES=10

Here's what the transfer looks like with -d file for an ~80MB file upload to the server:

• client side:

  show_file_upload(<gtk.ImageMenuItem object at 0x7f95f25496e0 (GtkImageMenuItem at 0x56554cae59c0)>,) can open=False
  load_contents: filename=/home/antoine/Downloads/NVIDIA-Linux-x86_64-361.45.11.run, 86205078 bytes, entity=1464443710:327571, response=-5
  send_file('/home/antoine/Downloads/NVIDIA-Linux-x86_64-361.45.11.run', '', <type 'str'>, '86205078 bytes', False, False, {})
  sha1 digest(/home/antoine/Downloads/NVIDIA-Linux-x86_64-361.45.11.run)=28d1586dd300c04f2e1ce66604a939bccfa51fa6
  ack-file-chunk: ['9f4c40d1ebf74aa69f02e8ebd866786c', True, '', 0]
  ack-file-chunk: ['9f4c40d1ebf74aa69f02e8ebd866786c', True, '', 1]
  ...
  ack-file-chunk: ['9f4c40d1ebf74aa69f02e8ebd866786c', True, '', 1316]
  1316 chunks of 65536 bytes sent in 17338ms (4MB/s)
  _check_chunk_sending(9f4c40d1ebf74aa69f02e8ebd866786c, 1316) chunk_state found: False
  

• server side:

  receiving file: ['bigfile', '', False, False, 86205078, '0 bytes', {'file-chunk-id': '9f4c40d1ebf74aa69f02e8ebd866786c', 'sha1': '28d1586dd300c04f2e1ce66604a939bccfa51fa6'}]
  using filename 'bigfile'
  _process_send_file_chunk('9f4c40d1ebf74aa69f02e8ebd866786c', 1, '65536 bytes', True)
  _process_send_file_chunk('9f4c40d1ebf74aa69f02e8ebd866786c', 2, '65536 bytes', True)
  ...
  sha1 digest matches: 28d1586dd300c04f2e1ce66604a939bccfa51fa6
  86205078 bytes received in 1316 chunks, took 16769ms
  downloaded 86205078 bytes to temporary file:
   '/home/guest/Downloads/bigfile'
  

---

@afarr: ready for testing, you should now be able to send or print big files without causing much of a slow down for anything else. Logging was also improved, small bugs fixed along the way. (I may backport some)

[J. Max Mena]

Did some testing of trunk r12814 file uploads (Fedora 23 both ends):

• All good with sending files - doesn't seem to hang anything anywhere.

Of note:

The select file dialogue will hang for a solid second or two if you try to upload a large file

[Antoine Martin]

r12815 closes the dialog more quickly and loads the file in the background as much as possible.

[Antoine Martin]

Milestone renamed

[alas]

Tested with a 1.0 r13101 win32 client against a 1.0 r13902 fedora 23 server.

Dialog closes very quickly, whether I'm uploading a 4 kb file or a 68 MB file, or even if I'm uploading a 218 MB file... though there wasn't anything to let me know that the 218 MB file was too ambitious, until I noticed the client side warning:

2016-09-28 17:31:12,180 Warning: cannot upload the file 'sound-test-weekend-log.txt'
2016-09-28 17:31:12,180  this file is too large: 218MB
2016-09-28 17:31:12,181  the local file size limit is 100MB

The session wasn't in any way impacted while uploading a 68 MB file though... so, other than considering a popup to warn a user of overzealous ambitions, I think this is ready to close.

[Antoine Martin]

new alert dialog

[Antoine Martin]

Good point. Alert dialog added in r13903, looks like this:

We also check the file size sooner and avoid trying to load really big files into memory before showing the error.

[J. Max Mena]

r13937 Trunk Windows 8.1 client against an r13937 Trunk Fedora 23 machine:

• Error noted in the popup (edited) when attempting to upload a 1.7GB ISO.

Not much else left here, closing.

[Antoine Martin]

See also drag and drop (#1493)