These remotes have no url configured, so git pull and push will fail.
git-annex sync --content etc can still sync with them otherwise.
Also, avoid git syncing twice with the same url. This is for cases where
a proxied remote has been manually configured and so does have a url.
Or perhaps proxied remotes will get configured like that automatically
later.
This does mean a redundant write to the git-annex branch. But,
it means that two clients can be using the same proxy, and after
one sends a file to a proxied remote, the other only has to pull from
the proxy to learn about that. It does not need to pull from every
remote behind the proxy (which it couldn't do anyway as git repo
access is not currently proxied).
Anyway, the overhead of this in git-annex branch writes is no worse
than eg, sending a file to a repository where git-annex assistant
is running, which then sends the file on to a remote, and updates
the git-annex branch then. Indeed, when the assistant also drops
the local copy, that results in more writes to the git-annex branch.
CONNECT is not supported by git-annex-shell p2pstdio, but for proxying
to tor-annex remotes, it will be supported, and will make a git pull/push
to a proxied remote work the same with that as it does over ssh,
eg it accesses the proxy's git repo not the proxied remote's git repo.
The p2p protocol docs say that NOTIFYCHANGES is not always supported,
and it looked annoying to implement it for this, and it also seems
pretty useless, so make it be a protocol error. git-annex remotedaemon
will already be getting change notifications from the proxy's git repo,
so there's no need to get additional redundant change notifications for
proxied remotes that would be for changes to the same git repo.
Prevent listProxied from listing anything when the proxy remote's
url is a local directory. Proxying does not work in that situation,
because the proxied remotes have the same url, and so git-annex-shell
is not run when accessing them, instead the proxy remote is accessed
directly.
I don't think there is any good way to support this. Even if the instantiated
git repos for the proxied remotes somehow used an url that caused it to use
git-annex-shell to access them, planned features like `git-annex copy --to
proxy` accepting a key and sending it on to nodes behind the proxy would not
work, since git-annex-shell is not used to access the proxy.
So it would need to use something to access the proxy that causes
git-annex-shell to be run and speaks P2P protocol over it. And we have that.
It's a ssh connection to localhost. Of course, it would be possible to
take ssh out of that mix, and swap in something that does not have
encryption overhead and authentication complications, but otherwise
behaves the same as ssh. And if the user wants to do that, GIT_SSH
does exist.
This just happened to work correctly. Rather surprisingly. It turns out
that openP2PSshConnection actually also supports local git remotes,
by just running git-annex-shell with the path to the remote.
Renamed "P2PSsh" to "P2PShell" to make this clear.
The almost identical code duplication between relayDATA and relayDATA'
is very annoying. I tried quite a few things to parameterize them, but
the type checker is having fits when I try it.
Memory use is small and constant; receiveBytes returns a lazy bytestring
and it does stream.
Comparing speed of a get of a 500 mb file over proxy from origin-origin,
vs from the same remote over a direct ssh:
joey@darkstar:~/tmp/bench/client>/usr/bin/time git-annex get bigfile --from origin-origin
get bigfile (from origin-origin...)
ok
(recording state in git...)
1.89user 0.67system 0:10.79elapsed 23%CPU (0avgtext+0avgdata 68716maxresident)k
0inputs+984320outputs (0major+10779minor)pagefaults 0swaps
joey@darkstar:~/tmp/bench/client>/usr/bin/time git-annex get bigfile --from direct-ssh
get bigfile (from direct-ssh...)
ok
1.79user 0.63system 0:10.49elapsed 23%CPU (0avgtext+0avgdata 65776maxresident)k
0inputs+1024312outputs (0major+9773minor)pagefaults 0swaps
So the proxy doesn't add much overhead even when run on the same machine as
the client and remote.
Still, piping receiveBytes into sendBytes like this does suggest that the proxy
could be made to use less CPU resouces by using `sendfile()`.
getRepoUUID looks at that, and was seeing the annex.uuid of the proxy.
Which caused it to unncessarily set the git config. Probably also would
have led to other problems.
Using the usual url download machinery even allows these urls to need
http basic auth, which is prompted for with git-credential. Which opens
the possibility for urls that contain a secret to be used, eg the cipher
for encryption=shared. Although the user is currently on their own
constructing such an url, I do think it would work.
Limited to httpalso for now, for security reasons. Since both httpalso
(and retrieving this very url) is limited by the usual
annex.security.allowed-ip-addresses configs, it's not possible for an
attacker to make one of these urls that sets up a httpalso url that
opens the garage door. Which is one class of attacks to keep in mind
with this thing.
It seems that there could be either a git-config that allows other types
of special remotes to be set up this way, or special remotes could
indicate when they are safe. I do worry that the git-config would
encourage users to set it without thinking through the security
implications. One remote config might be safe to access this way, but
another config, for one with the same type, might not be. This will need
further thought, and real-world examples to decide what to do.
And use it to set annex-config-uuid in git config. This makes
using the origin special remote work after cloning.
Without the added Logs.Remote.configSet, instantiating the remote will
look at the annex-config-uuid's config in the remote log, which will be
empty, and so it will fail to find a special remote.
The added deletion of files in the alternatejournaldir is just to make
100% sure they don't get committed to the git-annex branch. Now that
they contain things that definitely should not be committed.
cleanupInitialization gets run when an exception is thrown, so needs to
avoid throwing exceptions itself, as that would hide the error message
that the user needs to see.
When exporttree=yes is also set. Probably it would also be possible to
support ones with only importtree=yes, by enabling exporttree=yes for
the remote only when using git-remote-annex, but let's keep this
simple... I'm not sure what gets recorded in .git/annex/ state
differently in the two cases that might cause a problem when doing that.
Note that the full annex:: urls generated and displayed for such a
remote omit the importree=yes. Which is ok, cloning from such an url
uses an exporttree=remote, but the git-annex branch doesn't get written
by this program, so once the real config is available from the git-annex
branch, it will still function as an importree=yes remote.
This git bug also broke git-lfs, and I am confident it will be reverted
in the next release.
For now, cloning from an annex:: url wastes some bandwidth on the next
pull by not caching bundles locally.
If git doesn't fix this in the next version, I'd be tempted to rethink
whether bundle objects need to be cached locally. It would be possible to
instead remember which bundles have been seen and their heads, and
respond to the list command with the heads, and avoid unbundling them
agian in fetch. This might even be a useful performance improvement in
the latter case. It would be quite a complication to a currently simple
implementation though.
This fixes pushing a new ref that is the same as something already
pushed. In findotherprereq, it compares two shas, which didn't work when
one is actually not a sha but a ref.
This is one of those cases where Sha being an alias for Ref makes it
hard to catch mistakes. One of these days those need to be
differentiated at the type level, but not today..
Check explicitly for an annex:: url, not just any url. While no built-in
special remotes set an url, except ones that can be synced with, it
seems possible that some external special remote sets an url for its own
use, but did not expect it to be used by git-annex sync et al.
The assistant also syncs with them.
