Contributed by Steve Loughran.
This patch avoids issuing any HEAD path request when creating a file with overwrite=true,
so 404s will not end up in the S3 load balancers unless someone calls getFileStatus/exists/isFile
in their own code.
The Hadoop FsShell CommandWithDestination class is modified to not register uncreated files
for deleteOnExit(), because that calls exists() and so can place the 404 in the cache, even
after S3A is patched to not do it itself.
Because S3Guard knows when a file should be present, it adds a special FileNotFound retry policy
independently configurable from other retry policies; it is also exponential, but with
different parameters. This is because every HEAD request will refresh any 404 cached in
the S3 Load Balancers. It's not enough to retry: we have to have a suitable gap between
attempts to (hopefully) ensure any cached entry wil be gone.
The options and values are:
fs.s3a.s3guard.consistency.retry.interval: 2s
fs.s3a.s3guard.consistency.retry.limit: 7
The S3A copy() method used during rename() raises a RemoteFileChangedException which is not caught
so not downgraded to false. Thus: when a rename is unrecoverable, this fact is propagated.
Copy operations without S3Guard lack the confidence that the file exists, so don't retry the same way:
it will fail fast with a different error message. However, because create(path, overwrite=false) no
longer does HEAD path, we can at least be confident that S3A itself is not creating those cached
404 markers.
Change-Id: Ia7807faad8b9a8546836cb19f816cccf17cca26d
Contributed by Steve Loughran.
This overlaps the scanning for directory entries with batched calls to S3 DELETE and updates of the S3Guard tables.
It also uses S3Guard to list the files to delete, so find newly created files even when S3 listings are not use consistent.
For path which the client considers S3Guard to be authoritative, we also do a recursive LIST of the store and delete files; this is to find unindexed files and do guarantee that the delete(path, true) call really does delete everything underneath.
Change-Id: Ice2f6e940c506e0b3a78fa534a99721b1698708e
Contributed by Gabor Bota.
This pulls the tracking of the lastUpdated timestamp of metadata entries up from the DDB metastore into all s3guard stores, and then uses this to filter out expired tombstones from listings.
Change-Id: I80f121236b49c75a024116f65a3ef29d3580b462
Contributed by Steve Loughran and Gabor Bota.
This
* Asks S3Guard to determine the empty directory status.
* Has S3A's root directory rm("/") command to always return false (as abfs does)
* Documents that object stores MAY do this
* Overloads ContractTestUtils.assertDeleted to let assertions declare that the source directory does not need to exist. This stops inconsistencies in directory listings failing a root test.
It avoids a recent regression (HADOOP-16279) where if there was a tombstone above the first element found in a directory listing, the directory would be considered empty, when in fact there were child entries. That could downgrade an rm(path, recursive) to a no-op, while also confusing rename(src, dest), as dest could be mistaken for an empty directory and so permit the copy above it, rather than reject it "destination path exists and is not empty".
Change-Id: I136a3d1a5a48a67e6155d790a40ff558d0d2c108
Contributed by Steve Loughran
Contains
- HADOOP-16397. Hadoop S3Guard Prune command to support a -tombstone option.
- HADOOP-16406. ITestDynamoDBMetadataStore.testProvisionTable times out intermittently
This patch doesn't fix the underlying problem but it
* changes some tests to clean up better
* does a lot more in logging operations in against DDB, if enabled
* adds an entry point to dump the state of the metastore and s3 tables (precursor to fsck)
* adds a purge entry point to help clean up after a test run has got a store into a mess
* s3guard prune command adds -tombstone option to only clear tombstones
The outcome is that tests should pass consistently and if problems occur we have better diagnostics.
Change-Id: I3eca3f5529d7f6fec398c0ff0472919f08f054eb
Contributed by Steve Loughran.
This patch
* changes the default for the staging committer to append, as we get for the classic FileOutputFormat committer
* adds a check for the dest path being a file not a dir
* adds tests for this
* Changes AbstractCommitTerasortIT. to not use the simple parser, so fails if the file is present.
Change-Id: Id53742958ed1cf321ff96c9063505d64f3254f53
Contributed by Ben Roling.
S3Guard will now track the etag of uploaded files and, if an S3
bucket is versioned, the object version.
You can then control how to react to a mismatch between the data
in the DynamoDB table and that in the store: warn, fail, or, when
using versions, return the original value.
This adds two new columns to the table: etag and version.
This is transparent to older S3A clients -but when such clients
add/update data to the S3Guard table, they will not add these values.
As a result, the etag/version checks will not work with files uploaded by older clients.
For a consistent experience, upgrade all clients to use the latest hadoop version.
This is the first step for on-demand operations: things recognize when they are using on-demand tables,
as do the tests.
Contributed by Steve Loughran.
This is needed to fix up some confusion about caching of job.addCache() handling of S3A paths; all parent dirs -the files are downloaded by the NM without using the DTs of the user submitting the job. This means that when you submit jobs to an EC2 cluster with lower IAM permissions than the user, cached resources don't get downloaded and the job doesn't start.
Production code changes:
* S3AFileStatus Adds "true" to the superclass's encrypted flag during construction.
Tests
* Base AbstractContractOpenTest can control whether zero byte files created in tests are encrypted. Not done via an XML attribute, just a subclass point. Thoughts?
* Verify that the filecache considers paths to not have the permissions which trigger reduce-privilege downloads
* And extend ITestDelegatedMRJob to test a completely different bucket (open street map), to verify that cached resources do get their tokens picked up
Docs:
* Advise FS developers to say all files are encrypted. It's otherwise harmless and it'll stop other people seeing impossible to debug error messages on app launch.
Contributed by Steve Loughran.
Change-Id: Ifaae4c9d735ccc5eafeebd2584b65daf2d4e5da3
S3A to implement S3 Select through this API.
The new openFile() API is asynchronous, and implemented across FileSystem and FileContext.
The MapReduce V2 inputs are moved to this API, and you can actually set must/may
options to pass in.
This is more useful for setting things like s3a seek policy than for S3 select,
as the existing input format/record readers can't handle S3 select output where
the stream is shorter than the file length, and splitting plain text is suboptimal.
Future work is needed there.
In the meantime, any/all filesystem connectors are now free to add their own filesystem-specific
configuration parameters which can be set in jobs and used to set filesystem input stream
options (seek policy, retry, encryption secrets, etc).
Contributed by Steve Loughran
