Each command that first checks preferred content (and/or required
content) and then does something that can change the sizes of
repositories needs to call prepareLiveUpdate, and plumb it through the
preferred content check and the location log update.
So far, only Command.Drop is done. Many other commands that don't need
to do this have been updated to keep working.
There may be some calls to NoLiveUpdate in places where that should be
done. All will need to be double checked.
Not currently in a compilable state.
When getting from a P2P HTTP remote, prompt for credentials when required,
instead of failing.
This feels like it might be a bug in servant-client. withClientM's type
suggests it would not throw a ClientError. But it does in this case.
4f3ae96666 caused a hang in GET,
which git-annex testremote could reliably cause.
The problem is that closing both P2P handles before waiting on the
asyncworker prevents all the DATA from getting sent.
The solution is to only close the P2P handles early when the
P2PConnection is being closed. When it's being released, let the
asyncworker finish. closeP2PConnection is called in GET when it was
unable to send all data, and in PUT when it did not receive all the
data, and in both cases closing the P2P handles early is ok.
An interrupted PUT to cluster that has a node that is a special remote
over http left open the connection to the cluster, so the next request
opens another one. So did an interrupted PUT directly to the proxied
special remote over http.
proxySpecialRemote was stuck waiting for all the DATA. Its connection
remained open so it kept waiting.
In servePut, checktooshort handles closing the P2P connection
when too short a data is received from PUT. But, checktooshort was only
called after the protoaction, which is what runs the proxy, which is
what was getting stuck. Modified it to run as a background thread,
which waits for the tooshortv to be written to, which gather always does
once it gets to the end of the data received from the http client.
That makes proxyConnection's releaseconn run once all data is received
from the http client. Made it close the connection handles before
waiting on the asyncworker thread. This lets proxySpecialRemote finish
processing any data from the handle, and then it will give up,
more or less cleanly, if it didn't receive enough data.
I say "more or less cleanly" because with both sides of the P2P
connection taken down, some protocol unhappyness results. Which can lead
to some ugly debug messages. But also can cause the asyncworker thread
to throw an exception. So made withP2PConnections not crash when it
receives an exception from releaseconn.
This did have a small change to the behavior of an interrupted PUT when
proxying to a regular remote. proxyConnection has a protoerrorhandler
that closes the proxy connection on a protocol error. But the proxy
connection is also closed by checktooshort when it closes the P2P
connection. Closing the same proxy connection twice is not a problem,
it just results in duplicated debug messages about it.
An interrupted `git-annex copy --to` a cluster via the http server,
when repeated, failed. The http server output "transfer already in
progress, or unable to take transfer lock". Apparently a second
connection was opened to the cluster, because the first connection
never got shut down.
Turned out the problem was that when proxying to a cluster, it would read a
short ByteString from the client, and send that to the nodes. But that left the
nodes warning more. Meanwhile, the proxy was expecting a SUCCESS/FAILURE
message from the nodes. So it didn't return, and so the cluster connection
stayed open.
As seen in commit 770aac97a7, a cluster
relies accurate location logs. If long-running processes are serving a
cluster, and one process puts a file, the other process needs to see
what nodes it was stored on when checking if the file is present.
Sending ERROR caused the client to get confused and protocol to freeze.
Better to send empty DATA and indicate it's not valid.
This fixes a hang in git-annex testremote of a cluster accessed via the
http server. That testremote is still failing, for some reason after
storing a test key, the cluster reports it as not present.
Wired it up and it seems to basically work, although the test suite is
not fully passing.
Note that --jobs currently gets multiplied by the number of nodes in the
cluster, which is probably not good.
proxyRequest was treating UNLOCKCONTENT as a separate request.
That made it possible for there to be two different connections to the
proxied remote, with LOCKCONTENT being sent to one, and UNLOCKCONTENT
to the other one. A protocol error.
git-annex testremote now passes against a http proxied remote.
sendExactly will now be sure to evaluate the whole lazy ByteString.
In this case, the lazy ByteString was exactly the right lenth.
But, it seems that L.take caused it to not actually be fully evaluated.
In servePut, this manifested as gather never being fully evaluated,
which caused the hang.
Very, very subtle, and horrible bug. Clearly the use of lazy ByteString
(or really just laziness) is at fault, and it would be very worth moving
to conduit or whatever to avoid this.
removeOldestProxyConnectionPool will be innefficient the larger the pool
is. A better data structure could be more efficient. Eg, make each value
in the pool include the timestamp of its oldest element, then the oldest
value can be found and modified, rather than rebuilding the whole Map.
But, for pools of a few hundred items, this should be fine. It's O(n*n log n)
or so.
Also, when more than 1 connection with the same pool key exists,
it's efficient even for larger pools, since removeOldestProxyConnectionPool
is not needed.
The default of 1 idle connection could perhaps be larger.. like the
number of jobs? Otoh, it seems good to ramp up and down the number of
connections, which does happen. With 1, there is at most one stale
connection, which might cause a request to fail.
There was an annex worker thread that did not get stopped.
It was stuck in ReceiveMessage from the P2PHandleTMVar.
Fixed by making P2PHandleTMVar closeable.
In serveGet, releaseP2PConnection has to come first, else the
annexworker may not shut down, if it's waiting to read from it.
In proxyConnection, call closeRemoteSide in order to wait for the ssh
process (for example).
The proxy always checks the protocol version of a remote before talking
to it in a version-specific way, so the protocol version in the ProxyParams
is the client's protocol version. The remote will always be at the same or
an older protocol version than the client.
Note that in relayDATAFinish, when the client is at protocol version 0,
the remote must thus be as well, and that's why its version is not
checked in the case for that.
With that clarified, it's evident that, in P2P.Http.State, there's no
need to look at the proxied remote's protocol version at all.
Before it was leaving the protocol version at the default, when it
was actually v0.
v0 has only ever been used over tor, which is probably why this bug was
never noticed.
Refactored git-annex-shell code so this can use checkCanProxy'.
At this point all that remains is opening a proxy connection,
and using a proxy connection.
