Figure out how to view captured EXI messages on MacOS

[shankari]

We have some packet captures from the Testival and want to open them so we can see what we found.
@Abby-Wheelis @catarial for visibility

[shankari]

Per Zulip, the recommended method (https://lfenergy.zulipchat.com/#narrow/channel/417677-EVerest.3A-Car-com.2E/topic/EXI.20V2G.20Decoder.20Recommendations/near/443973418) is to

I always use Wireshark with the cbexigen plugin for debugging

But it is not clear which plugin this is.

I see two plugins on GitHub:

• https://github.com/dspace-group/dsV2Gshark but it only works for Windows and Linux
• https://github.com/ChargePoint/wireshark-v2g seems to have a mac version, but appears to use OpenV2G

  OpenV2G documentation: http://openv2g.sourceforge.net/
  Although looking at the source code, it includes

/* libcbv2g */
#include <cbv2g/iso_2/iso2_msgDefDatatypes.h>
#include <cbv2g/iso_2/iso2_msgDefDecoder.h>

which is from https://github.com/EVerest/libcbv2g

[shankari]

Trying the second one by downloading the macos version from both the releases and the GitHub artifacts, when I try to open the app, I get

[shankari]

Installing a fresh, unmodified version of wireshark allows us to open it again. Let's see if we can copy over the files per the README and get it to work.

[shankari]

Comparing the contents of the two, there are a lot more plugins in the more recent version. Let's fall back to a downloaded version that is the same version.

Even with the same version, there are some differences between the two, but they seem to be primarily related to UI (Qt***) or the keyboard. The main important difference seems to be the v2gexi.so in the new version. Let's try to copy it over and see what it does.
compare_working_not_working.zip

[shankari]

Bingo! I copied over the downloaded Wireshark.app/Contents/PlugIns/wireshark/4-2/epan/v2gexi.so to /Applications/Wireshark.app/Contents/PlugIns/wireshark/4-2/epan/

$ cp /tmp/Wireshark.app/Contents/PlugIns/wireshark/4-2/epan/v2gexi.so Wireshark.app/Contents/PlugIns/wireshark/4-2/epan/

Note that, per the README, we also need a lua file for the dissector, but I don't see any lua files

$ find /tmp/Wireshark.app | grep *.lua
$

So I checked out the repo

$ git clone https://github.com/ChargePoint/wireshark-v2g.git
$ cd wireshark-v2g

And then copied over the lua file

$ cp dissector/v2g.lua /Applications/Wireshark.app/Contents/PlugIns/wireshark

And that seems to work!