I'm stunned and stoked to have gotten git push over XMPP working today.
And am nearly out of steam, it was a wild ride..

	To xmpp::joey@kitenet.net
	  * [new branch]      master -> refs/xmpp/newmaster

The surprising part is how close my initial implementation came to just
working on the first try. It had around 3 bugs, which took hours of staring
at debugging output to find:

1. The git push action was run in the same thread as the XMPP
   client, which prevented the client from continuing to run and relaying
   messages.
2. The git-receive-pack side waited on the wrong thread, so didn't
   notice when the program was done.
3. I accidentally used the wrong attribute name when sending a ReceivePackDone
   message.

But all in all, it just worked.

Here's a sample of the actual data sent when one file is added to the
repository (also includes the corresponding update to the git-annex branch):

	MDA4NjhhMmNmOGZjMWE3MTlkOGVjOWVmOWZiMGZiNjVlODc2NjQ1NDAyMTAgODIwNTZjMDM4
	ZjU2YzE1ODdjYzllOWRhNzQzMzU0YjE4NzNjZWJlOSByZWZzL3htcHAvbmV3bWFzdGVyACBy
	ZXBvcnQtc3RhdHVzIHNpZGUtYmFuZC02NGswMDAw

	UEFDSwAAAAIAAAADnAx4nJXLTQ4CIQxA4T2n4AKaAqVAYoxL4y2gU+Jo5iczdeHtnSu4eMm3
	ebqJ2NwgSCLmNkTBlKFCYwwhoHOtQ+scqZCwWesms9pcPffc2dXkypCFi/TSG/RGUXIiwojg
	HZj60eey2cciX3uXfbeX18Hbe1SZRc9HV+tC9FgyJW9PgACGl2kaVeXfz/wArHQ81qMGeJwz
	NDIAAoVUI4ZZB9RW1E8NtXp5t77/fn3hw41cl2MNIbIZqTk5+Qwerw+aJX2INjsffYndtdCz
	5mZWLDdUQV5qeVpmDtCQnx/3/6s40+Q4P/7O+Y4ShS+1Ad83AwC6CirftAt4nK3MsRGDMAwF
	0IkcSVgSdpkidzRUmcDWBy4pSAEFl+mzRN4A77a9Tmr7vlz06e8lzoPmmb5Mz+k+mD/SkTkl
	eFHPq9eqQ+nSzFsWaDFnFmCMCEOvHgLrCrQxS7AWdvUVhv9uPwHxMbfumlvWdco1RLL4wSQF
	g0uFFOKu3Q==

Git said this push took 385 bytes; after base64 encoding to transport it over
XMPP as shown above, it needs 701 bytes, and the XMPP envelope and encryption
adds more overhead (although the XMPP connection may also be compressed?)

Not the most efficient git transport, but still a practical one!

----

Big thanks by the way to meep, who posted a comment reminding me about
`git-remote-helpers`. This was the right thing to use for XMPP over git,
it lets the git remote be configured with `url = xmpp::user@host`.

----

Next, I need to get the assistant to use this for syncing. Currently, it only
pushes a test branch.
