This fixes fsck of a remote that uses chunking displaying
(checking remotename) (checking remotename)" for every chunk.
Also, some remotes displayed the message, and others did not, with no
consistency. It was originally displayed only when accessing remotes
that were expensive or might involve a password prompt, I think, but
nothing in the API said when to do it so it became an inconsistent mess.
Originally I thought fsck should always display it. But it only displays
in fsck --from remote, so the user knows the remote is being accessed,
so there is no reason to tell them it's accessing it over and over.
It was also possible for git-annex move to sometimes display it twice,
due to checking if content is present twice. But, the user of move
specifies --from/--to, so it does not need to display when it's
accessing the remote, as the user expects it to access the remote.
git-annex get might display it, but only if the remote also supports
hasKeyCheap, which is really only local git remotes, which didn't
display it always; and in any case nothing displayed it before hasKeyCheap,
which is checked first, so I don't think this needs to display it ever.
mirror is like move. And that's all the main places it would have been
displayed.
This commit was sponsored by Jochen Bartl on Patreon.
This does not change the overall license of the git-annex program, which
was already AGPL due to a number of sources files being AGPL already.
Legally speaking, I'm adding a new license under which these files are
now available; I already released their current contents under the GPL
license. Now they're dual licensed GPL and AGPL. However, I intend
for all my future changes to these files to only be released under the
AGPL license, and I won't be tracking the dual licensing status, so I'm
simply changing the license statement to say it's AGPL.
(In some cases, others wrote parts of the code of a file and released it
under the GPL; but in all cases I have contributed a significant portion
of the code in each file and it's that code that is getting the AGPL
license; the GPL license of other contributors allows combining with
AGPL code.)
ghc 8 added backtraces on uncaught errors. This is great, but git-annex was
using error in many places for a error message targeted at the user, in
some known problem case. A backtrace only confuses such a message, so omit it.
Notably, commands like git annex drop that failed due to eg, numcopies,
used to use error, so had a backtrace.
This commit was sponsored by Ethan Aubin.
/dev/null stderr; ssh is still able to display a password prompt
despite this
Show some messages so the user knows it's locking a remote, and
knows if that locking failed.
This will allow special remotes to eg, open a http connection and reuse it,
while checking if chunks are present, or removing chunks.
S3 and WebDAV both need this to support chunks with reasonable speed.
Note that a special remote might want to cache a http connection across
multiple requests. A simple case of this is that CheckPresent is typically
called before Store or Remove. A remote using this interface can certianly
use a Preparer that eg, uses a MVar to cache a http connection.
However, it's up to the remote to then deal with things like stale or
stalled http connections when eg, doing a series of downloads from a remote
and other places. There could be long delays between calls to a remote,
which could lead to eg, http connection stalls; the machine might even
move to a new network, etc.
It might be nice to improve this interface later to allow
the simple case without needing to handle the full complex case.
One way to do it would be to have a `Transaction SpecialRemote cache`,
where SpecialRemote contains methods for Storer, Retriever, Remover, and
CheckPresent, that all expect to be passed a `cache`.
I tend to prefer moving toward explicit exception handling, not away from
it, but in this case, I think there are good reasons to let checkPresent
throw exceptions:
1. They can all be caught in one place (Remote.hasKey), and we know
every possible exception is caught there now, which we didn't before.
2. It simplified the code of the Remotes. I think it makes sense for
Remotes to be able to be implemented without needing to worry about
catching exceptions inside them. (Mostly.)
3. Types.StoreRetrieve.Preparer can only work on things that return a
Bool, which all the other relevant remote methods already did.
I do not see a good way to generalize that type; my previous attempts
failed miserably.
