[winswitch] Update for Xpra running Wireshark in Docker container

[Florian Feldhaus]

A while ago, I created a Docker image to run Wireshark via a Webbrowser. You can find the old mail thread here:
https://shifter-users.devloop.org.narkive.com/x5ibNYzP/winswitch-xpra-running-wireshark-in-docker-container <https://shifter-users.devloop.org.narkive.com/x5ibNYzP/winswitch-xpra-running-wireshark-in-docker-container>

I completely forgot about this, but recently discovered that it seems to be really popular (over 200K downloads of the image to date) and I decided to update the image (and will ask people to donate to Wireshark and XPRA if they like the image).

Mostly it is working fine, but there are a few errors / warnings from XPRA and some quality issues with the HTML5 client on high resolution displays (e.g. retina). Can you please help me understand or resolve these?

You can find the xpra.conf here:
https://github.com/ffeldhaus/docker-wireshark/blob/master/xpra.conf

Here’s the output from the XPRA start:
2019-10-11 13:54:03,413 Error: cannot enable SSH socket upgrades:
2019-10-11 13:54:03,413  No module named 'paramiko'
2019-10-11 13:54:03,414 created wss socket '0.0.0.0:14500'
2019-10-11 13:54:03,416 cannot access python uinput module:
2019-10-11 13:54:03,416  No module named 'uinput'
_XSERVTransmkdir: ERROR: euid != 0,directory /tmp/.X11-unix will not be created.

X.Org X Server 1.20.4
X Protocol Version 11, Revision 0
Build Operating System: Linux 4.9.0-8-amd64 x86_64 Debian
Current Operating System: Linux ad83385fffde 4.9.184-linuxkit #1 SMP Tue Jul 2 22:58:16 UTC 2019 x86_64
Kernel command line: BOOT_IMAGE=/boot/kernel console=ttyS0 console=ttyS1 page_poison=1 vsyscall=emulate panic=1 root=/dev/sr0 text
Build Date: 05 March 2019  08:11:12PM
xorg-server 2:1.20.4-1 (https://www.debian.org/support) 
Current version of pixman: 0.36.0
	Before reporting problems, check http://wiki.x.org
	to make sure that you have the latest version.
Markers: (--) probed, (**) from config file, (==) default setting,
	(++) from command line, (!!) notice, (II) informational,
	(WW) warning, (EE) error, (NI) not implemented, (??) unknown.
(++) Log file: "/run/user/1000/xpra/Xorg.S1.log", Time: Fri Oct 11 13:54:05 2019
(++) Using config file: "/etc/xpra/xorg.conf"
(==) Using system config directory "/usr/share/X11/xorg.conf.d"
2019-10-11 13:54:09,129 Error adding xauth entry for :0
2019-10-11 13:54:09,129  using command "xauth -f /home/wireshark/.Xauthority add :0 MIT-MAGIC-COOKIE-1 aeb28935775b4c6189a3b88cb67f90d3":
2019-10-11 13:54:09,129  [Errno 2] No such file or directory: 'xauth': 'xauth'
2019-10-11 13:54:09,252 created unix domain socket '/run/user/1000/xpra/ad83385fffde-0'
2019-10-11 13:54:09,316 pointer device emulation using XTest
2019-10-11 13:54:09,395 serving html content from '/usr/share/xpra/www'
2019-10-11 13:54:10,098 OpenGL is supported on display ':0'
2019-10-11 13:54:10,098  using 'llvmpipe (LLVM 8.0, 256 bits)' renderer
Warning: failed to import GStreamer 1.x:
 Namespace Gst not available
2019-10-11 13:54:10,286 Error: failed to query sound subsystem:
2019-10-11 13:54:10,286  query did not return any data

(Xpra:1): Gtk-CRITICAL **: 13:54:10.287: gtk_widget_realize: assertion 'widget->priv->anchored || GTK_IS_INVISIBLE (widget)' failed
2019-10-11 13:54:10,301 started command 'wireshark' with pid 45
2019-10-11 13:54:10,303 Warning: cannot watch for application menu changes without pyinotify:
2019-10-11 13:54:10,303  No module named 'pyinotify'
2019-10-11 13:54:10,307 Warning: cannot use application menu data:
2019-10-11 13:54:10,307  no python-xdg module
QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to '/tmp/runtime-wireshark'
nl80211 not found.
2019-10-11 13:54:10,497 xpra is ready.
2019-10-11 13:54:10,499 xpra GTK3 X11 version 3.0-r24095 64-bit
2019-10-11 13:54:10,550 2.0GB of system memory
2019-10-11 13:54:11,327  uid=1000 (wireshark), gid=1000 (wireshark)
2019-10-11 13:54:11,328  running with pid 1 on Linux Debian testing bullseye
2019-10-11 13:54:11,330  connected to X11 display :0 with 24 bit colors
2019-10-11 13:54:29,256 Error: wss request failure
2019-10-11 13:54:29,256  for client 172.17.0.1:39794:
2019-10-11 13:54:29,256  request: 'ü1ÿD5a>Gä•®Ç(’ñÑŠ3èÀ–lݐYCEò Dԩ̸ôþñÿÆŸ˜ó{}÷3Œ'o—
Åšð"ššÀ+À/À,À0̨̩ÀÀœ/5'
2019-10-11 13:54:29,256  [SSL: SSLV3_ALERT_CERTIFICATE_UNKNOWN] sslv3 alert certificate unknown (_ssl.c:2508)

Why is paramiko required?
Is it necessary or helpful to use uinput with the HTML5 client or can I just ignore the message that uinput is missing?
Is xauth mandatory? If so, why is it not part of the required dependencies?
Is it possible to disable the sound subsystem or should I just ignore that error?
What does the Gtk-CRITICAL message mean?
Is pyinotify required or helpful in this scenario? What is it used for?
I guess the SSLV3_ALERT_CERTIFICATE_UNKNOWN error is a result of using a self signed certificate. Is that correct?

When I use this on a large display (5K), I often get very blurred output when a lot of Network packages are analyzed. That is probably expected, but the blurry images sometimes stay for several seconds and sometimes are not refreshed at all with a clear picture. I tested this on a local computer with more or less unlimited bandwidth. I tried to modify the encoding settings via xpra.conf, but it seems they had no effect. I checked the information at https://xpra.org/trac/wiki/Encodings/Debugging <https://xpra.org/trac/wiki/Encodings/Debugging> but I wasn’t able to fix this myself. Are there any hints for high quality encoding?

Thank you very much
Florian