This change removes ListenableFutures.transformAsync in favor of the
existing Guava Futures.transform implementation. Our own implementation
had a bug which did not fail the future if the applied function threw an
exception, resulting in the future never completing.
An attempt was made to fix this bug, however when running againts Guava's own
tests, our version failed another half dozen tests, so it was decided to not
continue down that path and scrap our own implementation.
Explanation for how was this bug manifested itself:
An exception thrown in BaseAppenderatorDriver.publishInBackground when
invoked via transformAsync in StreamAppenderatorDriver.publish will
cause the resulting future to never complete.
This explains why when encountering https://github.com/apache/druid/issues/9845
the task will never complete, forever waiting for the publishFuture to
register the handoff. As a result, the corresponding "Error while
publishing segments ..." message only gets logged once the index task
times out and is forcefully shutdown when the future is force-cancelled
by the executor.
* refactor SeekableStreamSupervisor usage of RecordSupplier to reduce contention between background threads and main thread, refactor KinesisRecordSupplier, refactor Kinesis lag metric collection and emitting
* fix style and test
* cleanup, refactor, javadocs, test
* fixes
* keep collecting current offsets and lag if unhealthy in background reporting thread
* review stuffs
* add comment
* add flag to flattenSpec to keep null columns
* remove changes to inputFormat interface
* add comment
* change comment message
* update web console e2e test
* move keepNullColmns to JSONParseSpec
* fix merge conflicts
* fix tests
* set keepNullColumns to false by default
* fix lgtm
* change Boolean to boolean, add keepNullColumns to hash, add tests for keepKeepNullColumns false + true with no nuulul columns
* Add equals verifier tests
* add kinesis lag metric
* fixes
* heh
* do it right this time
* more test
* split out supervisor report lags into lagMillis, remove latest offsets from kinesis supervisor report since always null, review stuffs
* Reconcile terminology and method naming to 'used/unused segments'; Don't use terms 'enable/disable data source'; Rename MetadataSegmentManager to MetadataSegments; Make REST API methods which mark segments as used/unused to return server error instead of an empty response in case of error
* Fix brace
* Import order
* Rename withKillDataSourceWhitelist to withSpecificDataSourcesToKill
* Fix tests
* Fix tests by adding proper methods without interval parameters to IndexerMetadataStorageCoordinator instead of hacking with Intervals.ETERNITY
* More aligned names of DruidCoordinatorHelpers, rename several CoordinatorDynamicConfig parameters
* Rename ClientCompactTaskQuery to ClientCompactionTaskQuery for consistency with CompactionTask; ClientCompactQueryTuningConfig to ClientCompactionTaskQueryTuningConfig
* More variable and method renames
* Rename MetadataSegments to SegmentsMetadata
* Javadoc update
* Simplify SegmentsMetadata.getUnusedSegmentIntervals(), more javadocs
* Update Javadoc of VersionedIntervalTimeline.iterateAllObjects()
* Reorder imports
* Rename SegmentsMetadata.tryMark... methods to mark... and make them to return boolean and the numbers of segments changed and relay exceptions to callers
* Complete merge
* Add CollectionUtils.newTreeSet(); Refactor DruidCoordinatorRuntimeParams creation in tests
* Remove MetadataSegmentManager
* Rename millisLagSinceCoordinatorBecomesLeaderBeforeCanMarkAsUnusedOvershadowedSegments to leadingTimeMillisBeforeCanMarkAsUnusedOvershadowedSegments
* Fix tests, refactor DruidCluster creation in tests into DruidClusterBuilder
* Fix inspections
* Fix SQLMetadataSegmentManagerEmptyTest and rename it to SqlSegmentsMetadataEmptyTest
* Rename SegmentsAndMetadata to SegmentsAndCommitMetadata to reduce the similarity with SegmentsMetadata; Rename some methods
* Rename DruidCoordinatorHelper to CoordinatorDuty, refactor DruidCoordinator
* Unused import
* Optimize imports
* Rename IndexerSQLMetadataStorageCoordinator.getDataSourceMetadata() to retrieveDataSourceMetadata()
* Unused import
* Update terminology in datasource-view.tsx
* Fix label in datasource-view.spec.tsx.snap
* Fix lint errors in datasource-view.tsx
* Doc improvements
* Another attempt to please TSLint
* Another attempt to please TSLint
* Style fixes
* Fix IndexerSQLMetadataStorageCoordinator.createUsedSegmentsSqlQueryForIntervals() (wrong merge)
* Try to fix docs build issue
* Javadoc and spelling fixes
* Rename SegmentsMetadata to SegmentsMetadataManager, address other comments
* Address more comments
* Add JoinableFactory interface and use it in the query stack.
Also includes InlineJoinableFactory, which enables joining against
inline datasources. This is the first patch where a basic join query
actually works. It includes integration tests.
* Fix test issues.
* Adjustments from code review.
* Add FileUtils.createTempDir() and enforce its usage.
The purpose of this is to improve error messages. Previously, the error
message on a nonexistent or unwritable temp directory would be
"Failed to create directory within 10,000 attempts".
* Further updates.
* Another update.
* Remove commons-io from benchmark.
* Fix tests.
* Tidy up lifecycle, query, and ingestion logging.
The goal of this patch is to improve the clarity and usefulness of
Druid's logging for cluster operators. For more information, see
https://twitter.com/cowtowncoder/status/1195469299814555648.
Concretely, this patch does the following:
- Changes a lot of INFO logs to DEBUG, and DEBUG to TRACE, with the
goal of reducing redundancy and improving clarity by avoiding
showing rarely-useful log messages. This includes most "starting"
and "stopping" messages, and most messages related to individual
columns.
- Adds new log4j2 templates that show operators how to enabled DEBUG
logging for certain important packages.
- Eliminate stack traces for query errors, unless log level is DEBUG
or more. This is useful because query errors often indicate user
error rather than system error, but dumping stack trace often gave
operators the impression that there was a system failure.
- Adds task id to Appenderator, AppenderatorDriver thread names. In
the default log4j2 configuration, this will put them in log lines
as well. It's very useful if a user is using the Indexer, where
multiple tasks run in the same JVM.
- More consistent terminology when it comes to "sequences" (sets of
segments that are handed-off together by Kafka ingestion) and
"offsets" (cursors in partitions). These terms had been confused in
some log messages due to the fact that Kinesis calls offsets
"sequence numbers".
- Replaces some ugly toString calls with either the JSONification or
something more operator-accessible (like a URL or segment identifier,
instead of JSON object representing the same).
* Adjustments.
* Adjust integration test.
* Use earliest offset on kafka newly discovered partitions
* resolve conflicts
* remove redundant check cases
* simplified unit tests
* change test case
* rewrite comments
* add regression test
* add junit ignore annotation
* minor modifications
* indent
* override testableKafkaSupervisor and KafkaRecordSupplier to make the test runable
* modified test constructor of kafkaRecordSupplier
* simplify
* delegated constructor
* IndexerSQLMetadataStorageCoordinator.getTimelineForIntervalsWithHandle() don't fetch abutting intervals; simplify getUsedSegmentsForIntervals()
* Add VersionedIntervalTimeline.findNonOvershadowedObjectsInInterval() method; Propagate the decision about whether only visible segmetns or visible and overshadowed segments should be returned from IndexerMetadataStorageCoordinator's methods to the user logic; Rename SegmentListUsedAction to RetrieveUsedSegmentsAction, SegmetnListUnusedAction to RetrieveUnusedSegmentsAction, and UsedSegmentLister to UsedSegmentsRetriever
* Fix tests
* More fixes
* Add javadoc notes about returning Collection instead of Set. Add JacksonUtils.readValue() to reduce boilerplate code
* Fix KinesisIndexTaskTest, factor out common parts from KinesisIndexTaskTest and KafkaIndexTaskTest into SeekableStreamIndexTaskTestBase
* More test fixes
* More test fixes
* Add a comment to VersionedIntervalTimelineTestBase
* Fix tests
* Set DataSegment.size(0) in more tests
* Specify DataSegment.size(0) in more places in tests
* Fix more tests
* Fix DruidSchemaTest
* Set DataSegment's size in more tests and benchmarks
* Fix HdfsDataSegmentPusherTest
* Doc changes addressing comments
* Extended doc for visibility
* Typo
* Typo 2
* Address comment
* Add option lateMessageRejectionStartDate
* Use option lateMessageRejectionStartDate
* Fix tests
* Add lateMessageRejectionStartDate to kafka indexing service
* Update tests kafka indexing service
* Fix tests for KafkaSupervisorTest
* Add lateMessageRejectionStartDate to KinesisSupervisorIOConfig
* Fix var name
* Update documentation
* Add check lateMessageRejectionStartDateTime and lateMessageRejectionPeriod, fails if both were specified.
* Stateful auto compaction
* javaodc
* add removed test back
* fix test
* adding indexSpec to compactionState
* fix build
* add lastCompactionState
* address comments
* extract CompactionState
* fix doc
* fix build and test
* Add a task context to store compaction state; add javadoc
* fix it test
* get active task by datasource when supervisor discover tasks
* fix ut
* fix ut
* fix ut
* remove unnecessary condition check
* fix ut
* remove stream in hot loop
* Added live reports for Kafka and Native batch task
* Removed unused local variables
* Added the missing unit test
* Refine unit test logic, add implementation for HttpRemoteTaskRunner
* checksytle fixes
* Update doc descriptions for updated API
* remove unnecessary files
* Fix spellcheck complaints
* More details for api descriptions
* Fix dependency analyze warnings
Update the maven dependency plugin to the latest version and fix all
warnings for unused declared and used undeclared dependencies in the
compile scope. Added new travis job to add the check to CI. Also fixed
some source code files to use the correct packages for their imports and
updated druid-forbidden-apis to prevent regressions.
* Address review comments
* Adjust scope for org.glassfish.jaxb:jaxb-runtime
* Fix dependencies for hdfs-storage
* Consolidate netty4 versions
* LoggingEmitter: print event as json
* use DefaultRequestLogEventBuilderFactory in emitting request logger by default
* print context in query metric as json
* removed unused jsonMapper from DefaultQueryMetrics
* add comment
* remove change to DefaultRequestLogEventBuilderFactory.java
* check ctyle for constant field name
* check ctyle for constant field name
* check ctyle for constant field name
* check ctyle for constant field name
* check ctyle for constant field name
* check ctyle for constant field name
* check ctyle for constant field name
* check ctyle for constant field name
* check ctyle for constant field name
* merging with upstream
* review-1
* unknow changes
* unknow changes
* review-2
* merging with master
* review-2 1 changes
* review changes-2 2
* bug fix
* Add TaskResourceCleaner; fix a couple of concurrency bugs in batch tasks
* kill runner when it's ready
* add comment
* kill run thread
* fix test
* Take closeable out of Appenderator
* add javadoc
* fix test
* fix test
* update javadoc
* add javadoc about killed task
* address comment
* Add support for parallel native indexing with shuffle for perfect rollup.
* Add comment about volatiles
* fix test
* fix test
* handling missing exceptions
* more clear javadoc for stopGracefully
* unused import
* update javadoc
* Add missing statement in javadoc
* address comments; fix doc
* add javadoc for isGuaranteedRollup
* Rename confusing variable name and fix typos
* fix typos; move fetch() to a better home; fix the expiration time
* add support https
* Use partitionsSpec for all task types
* fix doc
* fix typos and revert to use isPushRequired
* address comments
* move partitionsSpec to core
* remove hadoopPartitionsSpec
* removed hard-coded Kafka key and value deserializer, leaving default deserializer as org.apache.kafka.common.serialization.ByteArrayDeserializer. Also added checks to ensure that any provided deserializer class extends org.apache.kafka.serialization.Deserializer and outputs a byte array.
* Addressed all comments from original pull request and also added a
unit test.
* Added additional test that uses "poll" to ensure that custom deserializer
works properly.
* Fix dependency analyze warnings
Update the maven dependency plugin to the latest version and fix all
warnings for unused declared and used undeclared dependencies in the
compile scope. Added new travis job to add the check to CI. Also fixed
some source code files to use the correct packages for their imports.
* Fix licenses and dependencies
* Fix licenses and dependencies again
* Fix integration test dependency
* Address review comments
* Fix unit test dependencies
* Fix integration test dependency
* Fix integration test dependency again
* Fix integration test dependency third time
* Fix integration test dependency fourth time
* Fix compile error
* Fix assert package
* doc updates and changes to use the CollectionUtils.mapValues utility method
* Add Structural Search patterns to intelliJ
* refactoring from PR comments
* put -> putIfAbsent
* do single key lookup
* disable all compression in intermediate segment persists while ingestion
* more changes and build fix
* by default retain existing indexingSpec for intermediate persisted segments
* document indexSpecForIntermediatePersists index tuning config
* fix build issues
* update serde tests
Make static imports forbidden in tests and remove all occurrences to be
consistent with the non-test code.
Also, various changes to files affected by above:
- Reformat to adhere to druid style guide
- Fix various IntelliJ warnings
- Fix various SonarLint warnings (e.g., the expected/actual args to
Assert.assertEquals() were flipped)
* Add state and error tracking for seekable stream supervisors
* Fixed nits in docs
* Made inner class static and updated spec test with jackson inject
* Review changes
* Remove redundant config param in supervisor
* Style
* Applied some of Jon's recommendations
* Add transience field
* write test
* implement code review changes except for reconsidering logic of markRunFinishedAndEvaluateHealth()
* remove transience reporting and fix SeekableStreamSupervisorStateManager impl
* move call to stateManager.markRunFinished() from RunNotice to runInternal() for tests
* remove stateHistory because it wasn't adding much value, some fixes, and add more tests
* fix tests
* code review changes and add HTTP health check status
* fix test failure
* refactor to split into a generic SupervisorStateManager and a specific SeekableStreamSupervisorStateManager
* fixup after merge
* code review changes - add additional docs
* cleanup KafkaIndexTaskTest
* add additional documentation for Kinesis indexing
* remove unused throws class
The main motivation is that this fixes#7724, by making it so the overlord
doesn't try to create a task runner and parser when all it really wants to
do is create a task object and serialize it.
* update easymock / powermock for to 4.0.2 / 2.0.2 for JDK11 support
* update tests to use new easymock interfaces
* fix tests failing due to easymock fixes
* remove dependency on jmockit
* fix race condition in ResourcePoolTest
* Moved Scan Builder to Druids class and started on Scan Benchmark setup
* Need to form queries
* It runs.
* Stuff for time-ordered scan query
* Move ScanResultValue timestamp comparator to a separate class for testing
* Licensing stuff
* Change benchmark
* Remove todos
* Added TimestampComparator tests
* Change number of benchmark iterations
* Added time ordering to the scan benchmark
* Changed benchmark params
* More param changes
* Benchmark param change
* Made Jon's changes and removed TODOs
* Broke some long lines into two lines
* nit
* Decrease segment size for less memory usage
* Wrote tests for heapsort scan result values and fixed bug where iterator
wasn't returning elements in correct order
* Wrote more tests for scan result value sort
* Committing a param change to kick teamcity
* Fixed codestyle and forbidden API errors
* .
* Improved conciseness
* nit
* Created an error message for when someone tries to time order a result
set > threshold limit
* Set to spaces over tabs
* Fixing tests WIP
* Fixed failing calcite tests
* Kicking travis with change to benchmark param
* added all query types to scan benchmark
* Fixed benchmark queries
* Renamed sort function
* Added javadoc on ScanResultValueTimestampComparator
* Unused import
* Added more javadoc
* improved doc
* Removed unused import to satisfy PMD check
* Small changes
* Changes based on Gian's comments
* Fixed failing test due to null resultFormat
* Added config and get # of segments
* Set up time ordering strategy decision tree
* Refactor and pQueue works
* Cleanup
* Ordering is correct on n-way merge -> still need to batch events into
ScanResultValues
* WIP
* Sequence stuff is so dirty :(
* Fixed bug introduced by replacing deque with list
* Wrote docs
* Multi-historical setup works
* WIP
* Change so batching only occurs on broker for time-ordered scans
Restricted batching to broker for time-ordered queries and adjusted
tests
Formatting
Cleanup
* Fixed mistakes in merge
* Fixed failing tests
* Reset config
* Wrote tests and added Javadoc
* Nit-change on javadoc
* Checkstyle fix
* Improved test and appeased TeamCity
* Sorry, checkstyle
* Applied Jon's recommended changes
* Checkstyle fix
* Optimization
* Fixed tests
* Updated error message
* Added error message for UOE
* Renaming
* Finish rename
* Smarter limiting for pQueue method
* Optimized n-way merge strategy
* Rename segment limit -> segment partitions limit
* Added a bit of docs
* More comments
* Fix checkstyle and test
* Nit comment
* Fixed failing tests -> allow usage of all types of segment spec
* Fixed failing tests -> allow usage of all types of segment spec
* Revert "Fixed failing tests -> allow usage of all types of segment spec"
This reverts commit ec470288c7.
* Revert "Merge branch '6088-Time-Ordering-On-Scans-N-Way-Merge' of github.com:justinborromeo/incubator-druid into 6088-Time-Ordering-On-Scans-N-Way-Merge"
This reverts commit 57033f36df, reversing
changes made to 8f01d8dd16.
* Check type of segment spec before using for time ordering
* Fix bug in numRowsScanned
* Fix bug messing up count of rows
* Fix docs and flipped boolean in ScanQueryLimitRowIterator
* Refactor n-way merge
* Added test for n-way merge
* Refixed regression
* Checkstyle and doc update
* Modified sequence limit to accept longs and added test for long limits
* doc fix
* Implemented Clint's recommendations
* Fix exclusivity for start offset in kinesis indexing service
* some adjustment
* Fix SeekableStreamDataSourceMetadata
* Add missing javadocs
* Add missing comments and unit test
* fix SeekableStreamStartSequenceNumbers.plus and add comments
* remove extra exclusivePartitions in KafkaIOConfig and fix downgrade issue
* Add javadocs
* fix compilation
* fix test
* remove unused variable
* Consolidate kafka consumer configs
* change the order of adding properties
* Add consumer properties to fix test
it seems kafka consumer does not reveive any message without these configs
* Use KafkaConsumerConfigs in integration test
* Update zookeeper and kafka versions in the setup.sh for the base druid image
* use version 0.2 of base druid image
* Try to fix tests in KafkaRecordSupplierTest
* unused import
* Fix tests in KafkaSupervisorTest
* Logic adjustments to SeekableStreamIndexTaskRunner.
A mix of simplifications and bug fixes. They are intermingled because
some of the bugs were made difficult to fix, and also more likely to
happen in the first place, by how the code was structured. I tried to
keep restructuring to a minimum. The changes are:
- Remove "initialOffsetsSnapshot", which was used to determine when to
skip start offsets. Replace it with "lastReadOffsets", which I hope
is more intuitive. (There is a connection: start offsets must be
skipped if and only if they have already been read, either by a
previous task or by a previous sequence in the same task, post-restoring.)
- Remove "isStartingSequenceOffsetsExclusive", because it should always
be the opposite of isEndOffsetExclusive. The reason is that starts are
exclusive exactly when the prior ends are inclusive: they must match
up in that way for adjacent reads to link up properly.
- Don't call "seekToStartingSequence" after the initial seek. There is
no reason to, since we expect to read continuous message streams
throughout the task. And calling it makes offset-tracking logic
trickier, so better to avoid the need for trickiness. I believe the
call being here was causing a bug in Kinesis ingestion where a
message might get double-read.
- Remove the "continue" calls in the main read loop. They are bad
because they prevent keeping currOffsets and lastReadOffsets up to
date, and prevent us from detecting that we have finished reading.
- Rework "verifyInitialRecordAndSkipExclusivePartition" into
"verifyRecordInRange". It no longer has side effects. It does a sanity
check on the message offset and also makes sure that it is not past
the endOffsets.
- Rework "assignPartitions" to replace inline comparisons with
"isRecordAlreadyRead" and "isMoreToReadBeforeReadingRecord" calls. I
believe this fixes an off-by-one error with Kinesis where the last
record would not get read. It also makes the logic easier to read.
- When doing the final publish, only adjust end offsets of the final
sequence, rather than potentially adjusting any unpublished sequence.
Adjusting sequences other than the last one is a mistake since it
will extend their endOffsets beyond what they actually read. (I'm not
sure if this was an issue in practice, since I'm not sure if real
world situations would have more than one unpublished sequence.)
- Rename "isEndSequenceOffsetsExclusive" to "isEndOffsetExclusive". It's
shorter and more clear, I think.
- Add equals/hashCode/toString methods to OrderedSequenceNumber.
Kafka test changes:
- Added a Kafka "testRestoreAtEndOffset" test to verify that restores at
the very end of the task lifecycle still work properly.
Kinesis test changes:
- Renamed "testRunOnNothing" to "testRunOnSingletonRange". I think that
given Kinesis semantics, the right behavior when start offset equals
end offset (and there aren't exclusive partitions set) is to read that
single offset. This is because they are both meant to be treated as
inclusive.
- Adjusted "testRestoreAfterPersistingSequences" to expect one more
message read. I believe the old test was wrong; it expected the task
not to read message number 5.
- Adjusted "testRunContextSequenceAheadOfStartingOffsets" to use a
checkpoint starting from 1 rather than 2. I believe the old test was
wrong here too; it was expecting the task to start reading from the
checkpointed offset, but it actually should have started reading from
one past the checkpointed offset.
- Adjusted "testIncrementalHandOffReadsThroughEndOffsets" to expect
11 messages read instead of 12. It's starting at message 0 and reading
up to 10, which should be 11 messages.
* Changes from code review.
* Throw caught exception.
* Throw caught exceptions.
* Related checkstyle rule is added to prevent further bugs.
* RuntimeException() is used instead of Throwables.propagate().
* Missing import is added.
* Throwables are propogated if possible.
* Throwables are propogated if possible.
* Throwables are propogated if possible.
* Throwables are propogated if possible.
* * Checkstyle definition is improved.
* Throwables.propagate() usages are removed.
* Checkstyle pattern is changed for only scanning "Throwables.propagate(" instead of checking lookbehind.
* Throwable is kept before firing a Runtime Exception.
* Fix unused assignments.
* wip
* fix tests, stop reading if we are at end offset
* fix build
* remove restore at end offsets fix in favor of a separate PR
* use typereference from method for serialization too
* Fix two SeekableStream serde issues.
1) Fix backwards-compatibility serde for SeekableStreamPartitions. It is needed
for split 0.13 / 0.14 clusters to work properly during a rolling update.
2) Abstract classes don't need JsonCreator constructors; remove them.
* Comment fixes.
* Added checkstyle for "Methods starting with Capital Letters" and changed the method names violating this.
* Un-abbreviate the method names in the calcite tests
* Fixed checkstyle errors
* Changed asserts position in the code
IndexTask had special-cased code to properly send a TaskToolbox to a
IngestSegmentFirehoseFactory that's nested inside a CombiningFirehoseFactory,
but ParallelIndexSubTask didn't.
This change refactors IngestSegmentFirehoseFactory so that it doesn't need a
TaskToolbox; it instead gets a CoordinatorClient and a SegmentLoaderFactory
directly injected into it.
This also refactors SegmentLoaderFactory so it doesn't depend on
an injectable SegmentLoaderConfig, since its only method always
replaces the preconfigured SegmentLoaderConfig anyway.
This makes it possible to use SegmentLoaderFactory without setting
druid.segmentCaches.locations to some dummy value.
Another goal of this PR is to make it possible for IngestSegmentFirehoseFactory
to list data segments outside of connect() --- specifically, to make it a
FiniteFirehoseFactory which can query the coordinator in order to calculate its
splits. See #7048.
This also adds missing datasource name URL-encoding to an API used by
CoordinatorBasedSegmentHandoffNotifier.
* Remove DataSegmentFinder, InsertSegmentToDb, and descriptor.json file
* delete descriptor.file when killing segments
* fix test
* Add doc for ha
* improve warning
* Support kafka transactional topics
* update kafka to version 2.0.0
* Remove the skipOffsetGaps option since it's not used anymore
* Adjust kafka consumer to use transactional semantics
* Update tests
* Remove unused import from test
* Fix compilation
* Invoke transaction api to fix a unit test
* temporary modification of travis.yml for debugging
* another attempt to get travis tasklogs
* update kafka to 2.0.1 at all places
* Remove druid-kafka-eight dependency from integration-tests, remove the kafka firehose test and deprecate kafka-eight classes
* Add deprecated in docs for kafka-eight and kafka-simple extensions
* Remove skipOffsetGaps and code changes for transaction support
* Fix indentation
* remove skipOffsetGaps from kinesis
* Add transaction api to KafkaRecordSupplierTest
* Fix indent
* Fix test
* update kafka version to 2.1.0
* Prohibit assigning concurrent maps into Map-types variables and fields; Fix a race condition in CoordinatorRuleManager; improve logic in DirectDruidClient and ResourcePool
* Enforce that if compute(), computeIfAbsent(), computeIfPresent() or merge() is called on a ConcurrentHashMap, it's stored in a ConcurrentHashMap-typed variable, not ConcurrentMap; add comments explaining get()-before-computeIfAbsent() optimization; refactor Counters; fix a race condition in Intialization.java
* Remove unnecessary comment
* Checkstyle
* Fix getFromExtensions()
* Add a reference to the comment about guarded computeIfAbsent() optimization; IdentityHashMap optimization
* Fix UriCacheGeneratorTest
* Workaround issue with MaterializedViewQueryQueryToolChest
* Strengthen Appenderator's contract regarding concurrency
* KillTask from overlord UI now makes sure that it terminates the underlying MR job, thus saving unnecessary compute
Run in jobby is now split into 2
1. submitAndGetHadoopJobId followed by 2. run
submitAndGetHadoopJobId is responsible for submitting the job and returning the jobId as a string, run monitors this job for completion
JobHelper writes this jobId in the path provided by HadoopIndexTask which in turn is provided by the ForkingTaskRunner
HadoopIndexTask reads this path when kill task is clicked to get hte jobId and fire the kill command via the yarn api. This is taken care in the stopGracefully method which is called in SingleTaskBackgroundRunner. Have enabled `canRestore` method to return `true` for HadoopIndexTask in order for the stopGracefully method to be called
Hadoop*Job files have been changed to incorporate the changes to jobby
* Addressing PR comments
* Addressing PR comments - Fix taskDir
* Addressing PR comments - For changing the contract of Task.stopGracefully()
`SingleTaskBackgroundRunner` calls stopGracefully in stop() and then checks for canRestore condition to return the status of the task
* Addressing PR comments
1. Formatting
2. Removing `submitAndGetHadoopJobId` from `Jobby` and calling writeJobIdToFile in the job itself
* Addressing PR comments
1. POM change. Moving hadoop dependency to indexing-hadoop
* Addressing PR comments
1. stopGracefully now accepts TaskConfig as a param
Handling isRestoreOnRestart in stopGracefully for `AppenderatorDriverRealtimeIndexTask, RealtimeIndexTask, SeekableStreamIndexTask`
Changing tests to make TaskConfig param isRestoreOnRestart to true
* Use multi-guava version friendly direct executor implementation
* Don't use a singleton
* Fix strict compliation complaints
* Copy Guava's DirectExecutor
* Fix javadoc
* Imports are the devil