- `repo.Repository` is now read-only and only has methods that can be supported over kopia server
- `repo.RepositoryWriter` has read-write methods that can be supported over kopia server
- `repo.DirectRepository` is read-only and contains all methods of `repo.Repository` plus some low-level methods for data inspection
- `repo.DirectRepositoryWriter` contains write methods for `repo.DirectRepository`
- `repo.Reader` removed and merged with `repo.Repository`
- `repo.Writer` became `repo.RepositoryWriter`
- `*repo.DirectRepository` struct became `repo.DirectRepository`
interface
Getting `{Direct}RepositoryWriter` requires using `NewWriter()` or `NewDirectWriter()` on a read-only repository and multiple simultaneous writers are supported at the same time, each writing to their own indexes and pack blobs.
`repo.Open` returns `repo.Repository` (which is also `repo.RepositoryWriter`).
* content: removed implicit flush on content manager close
* repo: added tests for WriteSession() and implicit flush behavior
* invalidate manifest manager after write session
* cli: disable maintenance in 'kopia server start'
Server will close the repository before completing.
* repo: unconditionally close RepositoryWriter in {Direct,}WriteSession
* repo: added panic in case somebody tries to create RepositoryWriter after closing repository
- used atomic to manage SharedManager.closed
* removed stale example
* linter: fixed spurious failures
Co-authored-by: Julio López <julio+gh@kasten.io>
* trivial: move CachingOptions out of content.Manager, where it's not needed
* trivial: removed newManagerWithOptions which was the same as NewManager
also moved one-time initialization to newReadManager()
* content: added support for cache of own writes
Thi keeps track of which blobs (n and m) have been written by the
local repository client, so that even if the storage listing
is eventually consistent (as in S3), we get somewhat sane behavior.
Note that this is still assumming read-after-create semantics, which
S3 also guarantees, otherwise it's very hard to do anything useful.
* compaction: support for compaction logs
Instead of compaction immediately deleting source index blobs, we now
write log entries (with `m` prefix) which are merged on reads
and applied only if the blob list includes all inputs and outputs, in
which case the inputs are discarded since they are known to have been
superseded by the outputs.
This addresses eventual consistency issues in stores such as S3,
which don't guarantee list-after-put or list-after-delete. With such
stores the repository is ultimately eventually consistent and there's
not much that can be done about it, unless we use second strongly
consistent storage (such as GCS) for the index only.
* content: updated list cache to cache both `n` and `m`
* repo: fixed cache clear on windows
Clearing cache requires closing repository first, as Windows is holding
the files locked.
This requires ability to close the repository twice.
* content: refactored index blob management into indexBlobManager
* testing: fixed blobtesting.Map storage to allow overwrites
* blob: added debug output String() to blob.Metadata
* testing: added indexBlobManager stress test
This works by using N parallel "actors", each repeatedly performing
operations on indexBlobManagers all sharing single eventually consistent
storage.
Each actor runs in a loop and randomly selects between:
- *reading* all contents in indexes and verifying that it includes
all contents written by the actor so far and that contents are
correctly marked as deleted
- *creating* new contents
- *deleting* one of previously-created contents (by the same actor)
- *compacting* all index files into one
The test runs on accelerated time (every read of time moves it by 0.1
seconds) and simulates several hours of running.
In case of a failure, the log should provide enough debugging
information to trace the exact sequence of events leading up to the
failure - each log line is prefixed with actorID and all storage
access is logged.
* makefile: increase test timeout
* content: fixed index blob manager race
The race is where if we delete compaction log too early, it may lead to
previously deleted contents becoming temporarily live again to an
outside observer.
Added test case that reproduces the issue, verified that it fails
without the fix and passed with one.
* testing: improvements to TestIndexBlobManagerStress test
- better logging to be able to trace the root cause in case of a failure
- prevented concurrent compaction which is unsafe:
The sequence:
1. A creates contentA1 in INDEX-1
2. B creates contentB1 in INDEX-2
3. A deletes contentA1 in INDEX-3
4. B does compaction, but is not seeing INDEX-3 (due to EC or simply
because B started read before #3 completed), so it writes
INDEX-4==merge(INDEX-1,INDEX-2)
* INDEX-4 has contentA1 as active
5. A does compaction but it's not seeing INDEX-4 yet (due to EC
or because read started before #4), so it drops contentA1, writes
INDEX-5=merge(INDEX-1,INDEX-2,INDEX-3)
* INDEX-5 does not have contentA1
7. C sees INDEX-5 and INDEX-5 and merge(INDEX-4,INDEX-5)
contains contentA1 which is wrong, because A has been deleted
(and there's no record of it anywhere in the system)
* content: when building pack index ensure index bytes are different each time by adding 32 random bytes
* This is 99% mechanical:
Extracted repo.Repository interface that only exposes high-level object and manifest management methods, but not blob nor content management.
Renamed old *repo.Repository to *repo.DirectRepository
Reviewed codebase to only depend on repo.Repository as much as possible, but added way for low-level CLI commands to use DirectRepository.
* PR fixes
This is mostly mechanical and changes how loggers are instantiated.
Logger is now associated with a context, passed around all methods,
(most methods had ctx, but had to add it in a few missing places).
By default Kopia does not produce any logs, but it can be overridden,
either locally for a nested context, by calling
ctx = logging.WithLogger(ctx, newLoggerFunc)
To override logs globally, call logging.SetDefaultLogger(newLoggerFunc)
This refactoring allowed removing dependency from Kopia repo
and go-logging library (the CLI still uses it, though).
It is now also possible to have all test methods emit logs using
t.Logf() so that they show up in failure reports, which should make
debugging of test failures suck less.
Also introduced strongly typed content.ID and manifest.ID (instead of string)
This aligns identifiers across all layers of repository:
blob.ID
content.ID
object.ID
manifest.ID
