* Remove IndexShard dependency from Repository
In order to simplify repository testing especially for BlobStoreRepository
it's important to remove the dependency on IndexShard and reduce it to
Store and MapperService (in the snapshot case). This significantly reduces
the dependcy footprint for Repository and allows unittesting without starting
nodes or instantiate entire shard instances. This change deprecates the old
method signatures and adds a unittest for FileRepository to show the advantage
of this change.
In addition, the unittesting surfaced a bug where the internal file names that
are private to the repository were used in the recovery stats instead of the
target file names which makes it impossible to relate to the actual lucene files
in the recovery stats.
* don't delegate deprecated methods
* apply comments
* test
When using High Level Rest Client Java API to produce search query, using AggregationBuilders.topHits("th").sort("_score", SortOrder.DESC)
caused query to contain duplicate sort clauses.
A shard that is undergoing peer recovery is subject to logging warnings of the form
org.elasticsearch.action.FailedNodeException: Failed node [XYZ]
...
Caused by: org.apache.lucene.index.IndexNotFoundException: no segments* file found in ...
These failures are actually harmless, and expected to happen while a peer recovery is ongoing (i.e.
there is an IndexShard instance, but no proper IndexCommit just yet).
As these failures are currently bubbled up to the master, they cause unnecessary reroutes and
confusion amongst users due to being logged as warnings.
Closes #40107
Moves the test infrastructure away from using node.max_local_storage_nodes, allowing us in a
follow-up PR to deprecate this setting in 7.x and to remove it in 8.0.
This also changes the behavior of InternalTestCluster so that starting up nodes will not automatically
reuse data folders of previously stopped nodes. If this behavior is desired, it needs to be explicitly
done by passing the data path from the stopped node to the new node that is started.
Simplifies the voting configuration reconfiguration logic by switching to an explicit Comparator for
the priorities. Does not make changes to the behavior of the component.
Flushing at the end of a peer recovery (if needed) can bring these
benefits:
1. Closing an index won't end up with the red state for a recovering
replica should always be ready for closing whether it performs the
verifying-before-close step or not.
2. Good opportunities to compact store (i.e., flushing and merging
Lucene, and trimming translog)
Closes#40024Closes#39588
This change verifies and aborts recovery if source and target have the
same syncId but different sequenceId. This commit also adds an upgrade
test to ensure that we always utilize syncId.
The verifying-before-close step ensures the global checkpoints on all
shard copies are in sync; thus, we don' t need to sync global
checkpoints for closed indices.
Relate #33888
There is an off-by-one error in this test. It leads to the recovery
thread never being started, and that means joining on it will wait
indefinitely. This commit addresses that by fixing the off-by-one error.
Relates #42325
I forgot to git add these before pushing, sorry. This commit fixes
compilation in IndexShardTests, they are needed here and not in master
due to differences in how Java infers types in generics between JDK 8
and JDK 11.
Today when executing an action on a primary shard under permit, we do
not enforce that the shard is in primary mode before executing the
action. This commit addresses this by wrapping actions to be executed
under permit in a check that the shard is in primary mode before
executing the action.
Today we are persisting the retention leases at least every thirty
seconds by a scheduled background sync. This sync causes an fsync to
disk and when there are a large number of shards allocated to slow
disks, these fsyncs can pile up and can severely impact the system. This
commit addresses this by only persisting and fsyncing the retention
leases if they have changed since the last time that we persisted and
fsynced the retention leases.
* Cleanup Various Uses of ActionListener
* Use shorter `map`, `runAfter` or `wrap` where functionally equivalent to anonymous class
* Use ActionRunnable where functionally equivalent
Downgrading an Elasticsearch node to an earlier version is unsupported, because
we do not make any attempt to guarantee that a node can read any of the on-disk
data written by a future version. Yet today we do not actively prevent
downgrades, and sometimes users will attempt to roll back a failed upgrade with
an in-place downgrade and get into an unrecoverable state.
This change adds the current version of the node to the node metadata file, and
checks the version found in this file against the current version at startup.
If the node cannot be sure of its ability to read the on-disk data then it
refuses to start, preserving any on-disk data in its upgraded state.
This change also adds a command-line tool to overwrite the node metadata file
without performing any version checks, to unsafely bypass these checks and
recover the historical and lenient behaviour.
Secure settings currently error if they exist inside elasticsearch.yml.
This commit adds validation that non-secure settings do not exist inside
the keystore.
closes#41831
The date_histogram accepts an interval which can be either a calendar
interval (DST-aware, leap seconds, arbitrary length of months, etc) or
fixed interval (strict multiples of SI units). Unfortunately this is inferred
by first trying to parse as a calendar interval, then falling back to fixed
if that fails.
This leads to confusing arrangement where `1d` == calendar, but
`2d` == fixed. And if you want a day of fixed time, you have to
specify `24h` (e.g. the next smallest unit). This arrangement is very
error-prone for users.
This PR adds `calendar_interval` and `fixed_interval` parameters to any
code that uses intervals (date_histogram, rollup, composite, datafeed, etc).
Calendar only accepts calendar intervals, fixed accepts any combination of
units (meaning `1d` can be used to specify `24h` in fixed time), and both
are mutually exclusive.
The old interval behavior is deprecated and will throw a deprecation warning.
It is also mutually exclusive with the two new parameters. In the future the
old dual-purpose interval will be removed.
The change applies to both REST and java clients.
If `keyedFilters` is null it assumes there are unkeyed filters...which
will NPE if the unkeyed filters was actually empty.
This refactors to simplify the filter assignment a bit, adds an empty
check and tidies up some formatting.
This commit fixes a test bug that ends up comparing the result of two consecutive calls to System.currentTimeMillis that can be different
on slow CIs.
Closes#42064
This test can create and shuffle 2*(3*5*7) = 210 shards which is quite
heavy for our CI. This commit reduces the load, so we don't timeout on
CI.
Closes#28153
Adds an initial limited implementations of geo features to SQL. This implementation is based on the [OpenGIS® Implementation Standard for Geographic information - Simple feature access](http://www.opengeospatial.org/standards/sfs), which is the current standard for GIS system implementation. This effort is concentrate on SQL option AKA ISO 19125-2.
Queries that are supported as a result of this initial implementation
Metadata commands
- `DESCRIBE table` - returns the correct column types `GEOMETRY` for geo shapes and geo points.
- `SHOW FUNCTIONS` - returns a list that includes supported `ST_` functions
- `SYS TYPES` and `SYS COLUMNS` display correct types `GEO_SHAPE` and `GEO_POINT` for geo shapes and geo points accordingly.
Returning geoshapes and geopoints from elasticsearch
- `SELECT geom FROM table` - returns the geoshapes and geo_points as libs/geo objects in JDBC or as WKT strings in console.
- `SELECT ST_AsWKT(geom) FROM table;` and `SELECT ST_AsText(geom) FROM table;`- returns the geoshapes ang geopoints in their WKT representation;
Using geopoints to elasticsearch
- The following functions will be supported for geopoints in queries, sorting and aggregations: `ST_GeomFromText`, `ST_X`, `ST_Y`, `ST_Z`, `ST_GeometryType`, and `ST_Distance`. In most cases when used in queries, sorting and aggregations, these function are translated into script. These functions can be used in the SELECT clause for both geopoints and geoshapes.
- `SELECT * FROM table WHERE ST_Distance(ST_GeomFromText(POINT(1 2), point) < 10;` - returns all records for which `point` is located within 10m from the `POINT(1 2)`. In this case the WHERE clause is translated into a range query.
Limitations:
Geoshapes cannot be used in queries, sorting and aggregations as part of this initial effort. In order to fully take advantage of geoshapes we would need to have access to geoshape doc values, which is coming in #37206. `ST_Z` cannot be used on geopoints in queries, sorting and aggregations since we don't store altitude in geo_point doc values.
Relates to #29872
Backport of #42031
This change updates tests that use a CountDownLatch to synchronize the
running of threads when testing concurrent operations so that we ensure
the thread has been fully created and run by the scheduler. Previously,
these tests used a latch with a value of 1 and the test thread counted
down while the threads performing concurrent operations just waited.
This change updates the value of the latch to be 1 + the number of
threads. Each thread counts down and then waits. This means that each
thread has been constructed and has started running. All threads will
have a common start point now.
Today we do not expose the cluster UUID in any logs by default, but it would be
useful to see it. For instance if a user starts multiple nodes as separate
clusters then they will silently remain as separate clusters even if they are
subsequently reconfigured to look like a single cluster. This change logs the
committed cluster UUID the first time the node encounters it.
* Switch to using a list instead of a Set for the filters, so that the
order of these filters is kept.
(cherry picked from commit 74a743829799b64971e0ac5ae265f43f6c14e074)
If remote recovery copies an index commit which has gaps in sequence
numbers to a follower; then these assertions (introduced in #40823)
don't hold for follower replicas.
Closes#41037
Currently IndexAnalyzers keeps the three default as separate class members
although they should refer to the same analyzers held in the additional
analyzers map under the default names. This assumption should be made more
explicit by keeping all analyzers in the map. This change adapts the constructor
to check all the default entries are there and the getters to reach into the map
with the default names when needed.
The changes in #39317 brought to light some concurrency issues in the
close method of Recyclers as we do not wait for threads running in the
threadpool to be finished prior to the closing of the PageCacheRecycler
and the Recyclers that are used internally. #41695 was opened to
address the concurrent close issues but upon review, the closing of
these classes is not really needed as the instances should be become
available for garbage collection once there is no longer a reference to
the closed node.
Closes#41683
We have a number of places in analysis-handling code where we check
if a field type is a keyword field, and if so then extract the normalizer rather
than pulling the index-time analyzer. However, a keyword normalizer is
really just a special case of an analyzer, so we should be able to simplify this
by setting the normalizer as the index-time analyzer at construction time.
* This test was resulting in a `PARTIAL` instead of a `SUCCESS` state for
the case of closing an index during snapshotting on 7.x
* The reason for this is the changed default behaviour regarding
waiting for active shards between 8.0 and 7.x
* Fixed by adjusting the waiting behaviour on the close index request
in the test
* Closes#39828
* When close becomes true while the management pool is shut down, we run
into an unhandled `EsRejectedExecutionException` that fails tests
* Found this while trying to reproduce #32506
* Running the IndexStatsIT in a loop is a way of reproducing this
Previously, TransportSingleShardAction required constructing a new
empty response object. This response object's Streamable readFrom
was used. As part of the migration to Writeable, the interface here
was updated to leverage Writeable.Reader.
relates to #34389.
The close method in Node uses a StopWatch to time to closing of
various services. However, the call to log the timing was made before
any of the services had been closed and therefore no timing would be
printed out. This change moves the timing log call to be a closeable
that is the last item closed.
This change makes the default seed address tests account for the lack
of an IPv6 network. By default docker containers only run with IPv4 and
these tests fail in a vanilla installation of elasticsearch-ci. To
resolve this we only expect IPv6 seed addresses if IPv6 is available.
Relates #41404
If the max doc in the index is greater than the minimum total term frequency
among the requested fields we need to adjust max doc to be equal to the min ttf.
This was removed by mistake when fixing #41125.
Closes#41934
The ReadOnlyEngine wraps its reader with a SoftDeletesDirectoryReaderWrapper if soft deletes
are enabled. However the wrapping is done on top of the ElasticsearchDirectoryReader and that
trips assertion later on since the cache key of these directories are different. This commit
changes the order of the wrapping to put the ElasticsearchDirectoryReader first in order to
ensure that it is always retrieved first when we unwrap the directory.
Closes#41795
* Allow unknown task time in QueueResizingEsTPE
The afterExecute method previously asserted that a TimedRunnable task
must have a positive execution time. However, the code in TimedRunnable
returns a value of -1 when a task time is unknown. Here, we expand the
logic in the assertion to allow for that possibility, and we don't
update our task time average if the value is negative.
* Add a failure flag to TimedRunnable
In order to be sure that a task has an execution time of -1 because of
a failure, I'm adding a failure flag boolean to the TimedRunnable class.
If execution time is negative for some other reason, an assertion will
fail.
Backport of #41810Fixes#41448
Prior to this change the ISO8601 date parser would only
parse an optional timezone if seconds were specified.
This change moves the timezone to the same level of
optional components as hour, so that timestamps without
minutes or seconds may optionally contain a timezone.
It also adds a unit test to cover all the supported
formats.
Allows configuring the number of test iterations via IntelliJ's config dialog, instead of having to add it
manually via the tests.iters system property.
* terminated_early should always be set in the response with terminate_after
Today we set `terminated_early` to true in the response if the query terminated
early due to `terminate_after`. However if `terminate_after` is smaller than
the number of documents in a shard we don't set the flag in the response indicating
that the query was exhaustive. This change fixes this disprepancy by setting
terminated_early to false in the response if the number of documents that match
the query is smaller than the provided `terminate_after` value.
Closes#33949
Today Elasticsearch accepts, but silently ignores, port ranges in the
`discovery.seed_hosts` setting:
```
discovery.seed_hosts: 10.1.2.3:9300-9400
```
Silently ignoring part of a setting like this is trappy. With this change we
reject seed host addresses of this form.
Closes#40786
Backport of #41404
Today if an exception is thrown when serializing a cluster state during
publication then the master enters a poisoned state where it cannot publish any
more cluster states, but nor does it stand down as master, yielding repeated
exceptions of the following form:
```
failed to commit cluster state version [12345]
org.elasticsearch.cluster.coordination.FailedToCommitClusterStateException: publishing failed
at org.elasticsearch.cluster.coordination.Coordinator.publish(Coordinator.java:1045) ~[elasticsearch-7.0.0.jar:7.0.0]
at org.elasticsearch.cluster.service.MasterService.publish(MasterService.java:252) [elasticsearch-7.0.0.jar:7.0.0]
at org.elasticsearch.cluster.service.MasterService.runTasks(MasterService.java:238) [elasticsearch-7.0.0.jar:7.0.0]
at org.elasticsearch.cluster.service.MasterService$Batcher.run(MasterService.java:142) [elasticsearch-7.0.0.jar:7.0.0]
at org.elasticsearch.cluster.service.TaskBatcher.runIfNotProcessed(TaskBatcher.java:150) [elasticsearch-7.0.0.jar:7.0.0]
at org.elasticsearch.cluster.service.TaskBatcher$BatchedTask.run(TaskBatcher.java:188) [elasticsearch-7.0.0.jar:7.0.0]
at org.elasticsearch.common.util.concurrent.ThreadContext$ContextPreservingRunnable.run(ThreadContext.java:681) [elasticsearch-7.0.0.jar:7.0.0]
at org.elasticsearch.common.util.concurrent.PrioritizedEsThreadPoolExecutor$TieBreakingPrioritizedRunnable.runAndClean(PrioritizedEsThreadPoolExecutor.java:252) [elasticsearch-7.0.0.jar:7.0.0]
at org.elasticsearch.common.util.concurrent.PrioritizedEsThreadPoolExecutor$TieBreakingPrioritizedRunnable.run(PrioritizedEsThreadPoolExecutor.java:215) [elasticsearch-7.0.0.jar:7.0.0]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) [?:1.8.0_144]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) [?:1.8.0_144]
at java.lang.Thread.run(Thread.java:748) [?:1.8.0_144]
Caused by: org.elasticsearch.cluster.coordination.CoordinationStateRejectedException: cannot start publishing next value before accepting previous one
at org.elasticsearch.cluster.coordination.CoordinationState.handleClientValue(CoordinationState.java:280) ~[elasticsearch-7.0.0.jar:7.0.0]
at org.elasticsearch.cluster.coordination.Coordinator.publish(Coordinator.java:1030) ~[elasticsearch-7.0.0.jar:7.0.0]
... 11 more
```
This is because it already created the publication request using
`CoordinationState#handleClientValue()` but then it fails before accepting it.
This commit addresses this by performing the serialization before calling
`handleClientValue()`.
Relates #41090, which was the source of such a serialization exception.
The fractional seconds portion of strict_date_optional_time was
accidentally copied from the printer, which always prints at least 3
fractional digits. This commit fixes the formatter to allow 1 or 2
fractional seconds.
closes#41633
Add a test that stresses concurrent writes using ifSeqno/ifPrimaryTerm to do CAS style updates. Use linearizability checker to verify linearizability. Linearizability of successful CAS'es is guaranteed.
Changed linearizability checker to allow collecting history concurrently.
Changed unresponsive network simulation to wake up immediately when network disruption is cleared to ensure tests proceed in a timely manner (and this also seems more likely to provoke issues).
Full text queries that start with now are not cacheable if they target a date field.
However we assume in the query builder tests that all queries are cacheable and this assumption
fails when the random generated query string starts with "now". This fails twice in several years
since the probability that a random string starts with "now" is low but this commit ensures that
isCacheable is correctly checked for full text queries that fall into this edge case.
Closes#41847
With this change, we will verify the consistency of version and source
(besides id, seq_no, and term) of live documents between shard copies
at the end of disruption tests.
If users close an index to change some non-dynamic index settings, then the current implementation forces replicas of that closed index to copy over segment files from the primary. With this change, we make peer recoveries of closed index skip both phases.
Relates #33888
Co-authored-by: Yannick Welsch <yannick@welsch.lu>
Exception message thrown when specifying illegal characters did
no accurately described the allowed characters. This updates the
error message to reflect reality (any character except [, ] and >)
When Elasticsearch is run from a package installation, the running
process does not have permissions to write to the keystore. This is
because of the root:root ownership of /etc/elasticsearch. This is why we
create the keystore if it does not exist during package installation. If
the keystore needs to be upgraded, that is currently done by the running
Elasticsearch process. Yet, as just mentioned, the Elasticsearch process
would not have permissions to do that during runtime. Instead, this
needs to be done during package upgrade. This commit adds an upgrade
command to the keystore CLI for this purpose, and that is invoked during
package upgrade if the keystore already exists. This ensures that we are
always on the latest keystore format before the Elasticsearch process is
invoked, and therefore no upgrade would be needed then. While this bug
has always existed, we have not heard of reports of it in practice. Yet,
this bug becomes a lot more likely with a recent change to the format of
the keystore to remove the distinction between file and string entries.
Today you can add a null `Custom` to the cluster state or its metadata, but
attempting to publish such a cluster state will fail. Unfortunately, the
publication-time failure gives very little information about the source of the
problem. This change causes the failure to manifest earlier and adds
information about which `Custom` was null in order to simplify the
investigation.
Relates #41090.
This changes the error message for a negative result in a function score when
using the ln modifier to suggest using ln1p or ln2p when a negative result
occurs in a function score and for the log modifier to suggest using log1p or
log2p.
This relates to #41509
This commit is a refactoring of how we filter addresses on
interfaces. In particular, we refactor all of these methods into a
common private method. We also change the order of logic to first check
if an address matches our filter and then check if the interface is
up. This is to possibly avoid problems we are seeing where devices are
flapping up and down while we are checking for loopback addresses. We do
not expect the loopback device to flap up and down so by reversing the
logic here we avoid that problem on CI machines. Finally, we expand the
error message when this does occur so that we know which device is
flapping.
This is related to #27260. Currently there is a setting
http.read_timeout that allows users to define a read timeout for the
http transport. This commit implements support for this functionality
with the transport-nio plugin. The behavior here is that a repeating
task will be scheduled for the interval defined. If there have been
no requests received since the last run and there are no inflight
requests, the channel will be closed.
Today a bulk shard request appears as follows in the detailed task list:
requests[42], index[my_index]
This change adds the shard index and refresh policy too:
requests[42], index[my_index][2], refresh[IMMEDIATE]
If closing a shard while resetting engine,
IndexEventListener.afterIndexShardClosed would be called while there is
still an active IndexWriter on the shard. For integration tests, this
leads to an exception during check index called from MockFSIndexStore
.Listener. Fixed.
Relates to #38561
Today we allow adding entries from a file or from a string, yet we
internally maintain this distinction such that if you try to add a value
from a file for a setting that expects a string or add a value from a
string for a setting that expects a file, you will have a bad time. This
causes a pain for operators such that for each setting they need to know
this difference. Yet, we do not need to maintain this distinction
internally as they are bytes after all. This commit removes that
distinction and includes logic to upgrade legacy keystores.
Today we choose to initialize max_seq_no_of_updates on primaries only so
we can deal with a situation where a primary is on an old node (before
6.5) which does not have MUS while replicas on new nodes (6.5+).
However, this strategy is quite complex and can lead to bugs (for
example #40249) since we have to assign a correct value (not too low) to
MSU in all possible situations (before recovering from translog,
restoring history on promotion, and handing off relocation).
Fortunately, we don't have to deal with this BWC in 7.0+ since all nodes
in the cluster should have MSU. This change simplifies the
initialization of MSU by always assigning it a correct value in the
constructor of Engine regardless of whether it's a replica or primary.
Relates #33842
IntervalsSources can throw IllegalArgumentExceptions if they would produce
too many disjunctions. To mitigate against this when building random
sources, we limit the depth of the randomly generated source to four
nested sources
Fixes#41402
* Add Repository Consistency Assertion to SnapshotResiliencyTests (#40857)
* Add Repository Consistency Assertion to SnapshotResiliencyTests
* Add some quick validation on not leaving behind any dangling metadata or dangling indices to the snapshot resiliency tests
* Added todo about expanding this assertion further
* Fix SnapshotResiliencyTest Repo Consistency Check (#41332)
* Fix SnapshotResiliencyTest Repo Consistency Check
* Due to the random creation of an empty `extra0` file by the Lucene mockFS we see broken tests because we use the existence of an index folder in assertions and the index deletion doesn't go through if there are extra files in an index folder
* Fixed by removing the `extra0` file and resulting empty directory trees before asserting repo consistency
* Closes#41326
* Reenable SnapshotResiliency Test (#41437)
This was fixed in https://github.com/elastic/elasticsearch/pull/41332
but I forgot to reenable the test.
* fix compile on java8
A stuck peer recovery in #40913 reveals that we indefinitely retry on
new cluster states if indexing translog operations hits a mapper
exception. We should not wait and retry if the mapping on the target is
as recent as the mapping that the primary used to index the replaying
operations.
Relates #40913
This commit refactors GeoHashUtils class into a new Geohash utility class located in the ES geo library. The intent is to not only better control what geo methods are whitelisted for painless scripting but to clean up the geo utility API in general.
Motivated by slow snapshot deletes reported in e.g. #39656 and the fact that these likely are a contributing factor to repositories accumulating stale files over time when deletes fail to finish in time and are interrupted before they can complete.
* Makes snapshot deletion async and parallelizes some steps of the delete process that can be safely run concurrently via the snapshot thread poll
* I did not take the biggest potential speedup step here and parallelize the shard file deletion because that's probably better handled by moving to bulk deletes where possible (and can still be parallelized via the snapshot pool where it isn't). Also, I wanted to keep the size of the PR manageable.
* See https://github.com/elastic/elasticsearch/pull/39656#issuecomment-470492106
* Also, as a side effect this gives the `SnapshotResiliencyTests` a little more coverage for master failover scenarios (since parallel access to a blob store repository during deletes is now possible since a delete isn't a single task anymore).
* By adding a `ThreadPool` reference to the repository this also lays the groundwork to parallelizing shard snapshot uploads to improve the situation reported in #39657
* Thanks to #39793 dynamic mapping updates don't contain blocking operations anymore so we don't have to manually put the mapping in this test and can keep it a little simpler
* Add Restore Operation to SnapshotResiliencyTests
* Expand the successful snapshot test case to also include restoring the snapshop
* Add indexing of documents as well to be able to meaningfully verify the restore
* This is part of the larger effort to test eventually consistent blob stores in #39504
* The check doesn't add much if anything practically, since the S3 repository is eventually consistent and we only log the non-existence of a blob anyway
* We don't do the check on writes for this very reason and documented it as such
* Removing the check saves one API call per single delete speeding up the deletion process and lowering costs
Today the `_field_caps` API returns the list of indices where a field
is present only if this field has different types within the requested indices.
However if the request is an index pattern (or an alias, or both...) there
is no way to infer the indices if the response contains only fields that have
the same type in all indices. This commit changes the response to always return
the list of indices in the response. It also adds a way to retrieve unmapped field
in a specific section per field called `unmapped`. This section is created for each field
that is present in some indices but not all if the parameter `include_unmapped` is set to
true in the request (defaults to false).
* Introduce Delegating ActionListener Wrappers
* Dry up use cases of ActionListener that simply pass through the response or exception to another listener
* Name Snapshot Data Blobs by UUID
* There is no functional reason why we need incremental naming for these files but
* As explained in #38941 it is a possible source of corrupting the repository
* It wastes API calls for the list operation
* Is just needless complication
* Since we store the exact names of the data blobs in all the metadata anyway, we can make this change without any BwC considerations
* Even on the worst case scenario of a downgrade the functionality would continue working since the incremental names wouldn't conflict with the uuids and the number parsing for finding the next incremental name suppresses the exception when encountring a non-numeric value after the double underscore prefix
In order to support empty action metadata in the first msearch item,
we need to remove support for prepending msearch request body with an
empty line, which prevents us from parsing the empty line as action
metadata for the first search item.
Relates to #41011
Yannick Welsch
Simon Willnauer
Ignacio Vera
Nhat Nguyen
Jason Tedor
Armin Braun
Henning Andersen
David Turner
Jake Landis
Ryan Ernst
Zachary Tong
Alexander Reelsen
Jim Ferenczi
Igor Motov
Jay Modi
Yogesh Gaikwad
Andrei Stefan
Christoph Büscher
Alan Woodward
Tal Levy
David Kyle
Benjamin Trent
William Brafford
David Roberts
Jim Ferenczi
Przemyslaw Gomulka
Hicham Mallah
Issam EL-ATIF
Jack Conradson
Colin Goodheart-Smithe
Tim Brooks
Andy Bristol
Dan Hermann
Michael Morello
Nick Knize
Ignacio Vera
Luca Cavanna