This will allow disabling exports for remotes that are not configured to
allow them. Also, exportSupported will be useful for the external
special remote to probe.
This commit was supported by the NSF-funded DataLad project
Implemented so far for the directory special remote.
Several remotes don't make sense to export to. Regular Git remotes,
obviously, do not. Bup remotes almost certianly do not, since bup would
need to be used to extract the export; same store for Ddar. Web and
Bittorrent are download-only. GCrypt is always encrypted so exporting to
it would be pointless. There's probably no point complicating the Hook
remotes with exporting at this point. External, S3, Glacier, WebDAV,
Rsync, and possibly Tahoe should be modified to support export.
Thought about trying to reuse the storeKey/retrieveKeyFile/removeKey
interface, rather than adding a new interface. But, it seemed better to
keep it separate, to avoid a complicated interface that sometimes
encrypts/chunks key/value storage and sometimes users non-key/value
storage. Any common parts can be factored out.
Note that storeExport is not atomic.
doc/design/exporting_trees_to_special_remotes.mdwn has some things in
the "resuming exports" section that bear on this decision. Basically,
I don't think, at this time, that an atomic storeExport would help with
resuming, because exports are not key/value storage, and we can't be
sure that a partially uploaded file is the same content we're currently
trying to export.
Also, note that ExportLocation will always use unix path separators.
This is important, because users may export from a mix of windows and
unix, and it avoids complicating the API with path conversions,
and ensures that in such a mix, they always use the same locations for
exports.
This commit was sponsored by Bruno BEAUFILS on Patreon.
Most remotes have an idempotent setup that can be reused for
enableremote, but in a few cases, it needs to tell which, and whether
a UUID was provided to setup was used.
This is groundwork for making initremote be able to provide a UUID.
It should not change any behavior.
Note that it would be nice to make the UUID always be provided to setup,
and make setup not need to generate and return a UUID. What prevented
this simplification is Remote.Git.gitSetup, which needs to reuse the
UUID of the git remote when setting it up, and so has to return that
UUID.
This commit was sponsored by Thom May on Patreon.
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.
Removed the instance LensGpgEncParams RemoteConfig because it encouraged
code that does not take the RemoteGitConfig into account.
RemoteType's setup was changed to take a RemoteGitConfig,
although the only place that is able to provide a non-empty one is
enableremote, when it's changing an existing remote. This led to several
folow-on changes, and got RemoteGitConfig plumbed through.
That trailing slash is needed for legacy chunked mode, because it puts the
chunks in a subdir under the key. But, outside legacy chunked mode, it's BS
and it's amazing it worked at all with some webdav servers.
sideAction is for things not generally related to the current action being
performed. And, it adds a newline after the side action. This was not the
right thing to use for stuff like "checksum", where doing a checksum is
part of the git annex get process, and indeed we want it to display
"(checksum...) ok"
Now it suffices to run git remote add, followed by git-annex sync. Now the
remote is automatically initialized for use by git-annex, where before the
git-annex branch had to manually be pushed before using git-annex sync.
Note that this involved changes to git-annex-shell, so if the remote is
using an old version, the manual push is still needed.
Implementation required git-annex-shell be changed, so configlist can
autoinit a repository even when no git-annex branch has been pushed yet.
Unfortunate because we'll have to wait for it to get deployed to servers
before being able to rely on this change in the documentation.
Did consider making git-annex sync push the git-annex branch to repos that
didn't have a uuid, but this seemed difficult to do without complicating it
in messy ways.
It would be cleaner to split a command out from configlist to handle
the initialization. But this is difficult without sacrificing backwards
compatability, for users of old git-annex versions which would not use the
new command.
That and S3 are all that uses creds currently, except that external
remotes can use creds. I have not handled showing info about external
remote creds because they can have 0, 1, or more separate cred pairs, and
there's no way for info to enumerate them or know how they're used.
So it seems ok to leave out creds info for external remotes.
Now `git annex info $remote` shows info specific to the type of the remote,
for example, it shows the rsync url.
Remote types that support encryption or chunking also include that in their
info.
This commit was sponsored by Ævar Arnfjörð Bjarmason.
encryptionSetup must be called before setRemoteCredPair. Otherwise,
the RemoteConfig doesn't have the cipher in it, and so no cipher is used to
encrypt the embedded creds.
This is a security fix for non-shared encryption methods!
For encryption=shared, there's no security problem, just an
inconsistentency in whether the embedded creds are encrypted.
This is very important to get right, so used some types to help ensure that
setRemoteCredPair is only run after encryptionSetup. Note that the external
special remote bypasses the type safety, since creds can be set after the
initial remote config, if the external special remote program requests it.
Also note that IA remotes never use encryption, so encryptionSetup is not
run for them at all, and again the type safety is bypassed.
This leaves two open questions:
1. What to do about S3 and glacier remotes that were set up
using encryption=pubkey/hybrid with embedcreds?
Such a git repo has a security hole embedded in it, and this needs to be
communicated to the user. Is the changelog enough?
2. enableremote won't work in such a repo, because git-annex will
try to decrypt the embedded creds, which are not encrypted, so fails.
This needs to be dealt with, especially for ecryption=shared repos,
which are not really broken, just inconsistently configured.
Noticing that problem for encryption=shared is what led to commit
fbdeeeed5f, which tried to
fix the problem by not decrypting the embedded creds.
This commit was sponsored by Josh Taylor.
Added a mkUnavailable method, which a Remote can use to generate a version
of itself that is not available. Implemented for several, but not yet all
remotes.
This allows testing that checkPresent properly throws an exceptions when
it cannot check if a key is present or not. It also allows testing that the
other methods don't throw exceptions in these circumstances.
This immediately found several bugs, which this commit also fixes!
* git remotes using ssh accidentially had checkPresent return
an exception, rather than throwing it
* The chunking code accidentially returned False rather than
propigating an exception when there were no chunks and
checkPresent threw an exception for the non-chunked key.
This commit was sponsored by Carlo Matteo Capocasa.
Removed old extensible-exceptions, only needed for very old ghc.
Made webdav use Utility.Exception, to work after some changes in DAV's
exception handling.
Removed Annex.Exception. Mostly this was trivial, but note that
tryAnnex is replaced with tryNonAsync and catchAnnex replaced with
catchNonAsync. In theory that could be a behavior change, since the former
caught all exceptions, and the latter don't catch async exceptions.
However, in practice, nothing in the Annex monad uses async exceptions.
Grepping for throwTo and killThread only find stuff in the assistant,
which does not seem related.
Command.Add.undo is changed to accept a SomeException, and things
that use it for rollback now catch non-async exceptions, rather than
only IOExceptions.
This speeds up the webdav special remote somewhat, since it often now
groups actions together in a single http connection when eg, storing a
file.
Legacy chunks are still supported, but have not been sped up.
This depends on a as-yet unreleased version of DAV.
This commit was sponsored by Thomas Hochstein.
Reusing http connection when operating on chunks is not done yet,
I had to submit some patches to DAV to support that. However, this is no
slower than old-style chunking was.
Note that it's a fileRetriever and a fileStorer, despite DAV using
bytestrings that would allow streaming. As a result, upload/download of
encrypted files is made a bit more expensive, since it spools them to temp
files. This was needed to get the progress meters to work.
There are probably ways to avoid that.. But it turns out that the current
DAV interface buffers the whole file content in memory, and I have
sent in a patch to DAV to improve its interfaces. Using the new interfaces,
it's certainly going to need to be a fileStorer, in order to read the file
size from the file (getting the size of a bytestring would destroy
laziness). It should be possible to use the new interface to make it be a
byteRetriever, so I'll change that when I get to it.
This commit was sponsored by Andreas Olsson.
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.
Moved old legacy chunking code, and cleaned up the directory and webdav
remotes use of it, so when no chunking is configured, that code is not
used.
The config for new style chunking will be chunk=1M instead of chunksize=1M.
There should be no behavior changes from this commit.
This commit was sponsored by Andreas Laas.
