Console.readText may return null in certain cases. This commit fixes a
bug in Terminal.promptYesNo which assumed a non-null return value. It
also adds a test for this, and modifies mock terminal to be able to
handle null input values.
In #23253 we added an the ability to incrementally reduce search results.
This change exposes the parameter to control the batch since and therefore
the memory consumption of a large search request.
Today all query results are buffered up until we received responses of
all shards. This can hold on to a significant amount of memory if the number of
shards is large. This commit adds a first step towards incrementally reducing
aggregations results if a, per search request, configurable amount of responses
are received. If enough query results have been received and buffered all so-far
received aggregation responses will be reduced and released to be GCed.
This commit cleans up some parsing tests added from the High Level Rest Client: IndexResponseTests, DeleteResponseTests, UpdateResponseTests, BulkItemResponseTests.
These tests are now more uniform with the others test-from-to-XContent tests we have, they now shuffle the XContent fields before parsing, the asserting method for parsed objects does not used a Map<String, Object> anymore, and buggy equals/hasCode methods in ShardInfo and ShardInfo.Failure have been removed.
This commit enforces the requirement of Content-Type for the REST layer and removes the deprecated methods in transport
requests and their usages.
While doing this, it turns out that there are many places where *Entity classes are used from the apache http client
libraries and many of these usages did not specify the content type. The methods that do not specify a content type
explicitly have been added to forbidden apis to prevent more of these from entering our code base.
Relates #19388
With #22977, network disruption also disconnects nodes from the transport service. That has the side effect that when the disruption is healed, the disconnected node stay disconnected until the `NodeConnectionsService` restores the connection. This can take too long for the tests. This PR adds logic to the cluster healing to restore connections immediately.
See https://elasticsearch-ci.elastic.co/job/elastic+elasticsearch+master+multijob-unix-compatibility/os=debian/611/console for an example failure.
When nested objects are present in the mappings, many queries get deoptimized
due to the need to exclude documents that are not in the right space. For
instance, a filter is applied to all queries that prevents them from matching
non-root documents (`+*:* -_type:__*`). Moreover, a filter is applied to all
child queries of `nested` queries in order to make sure that the child query
only matches child documents (`_type:__nested_path`), which is required by
`ToParentBlockJoinQuery` (the Lucene query behing Elasticsearch's `nested`
queries).
These additional filters slow down `nested` queries. In 1.7-, the cost was
somehow amortized by the fact that we cached filters very aggressively. However,
this has proven to be a significant source of slow downs since 2.0 for users
of `nested` mappings and queries, see #20797.
This change makes the filtering a bit smarter. For instance if the query is a
`match_all` query, then we need to exclude nested docs. However, if the query
is `foo: bar` then it may only match root documents since `foo` is a top-level
field, so no additional filtering is required.
Another improvement is to use a `FILTER` clause on all types rather than a
`MUST_NOT` clause on all nested paths when possible since `FILTER` clauses
are more efficient.
Here are some examples of queries and how they get rewritten:
```
"match_all": {}
```
This query gets rewritten to `ConstantScore(+*:* -_type:__*)` on master and
`ConstantScore(_type:AutomatonQuery {\norg.apache.lucene.util.automaton.Automaton@4371da44})`
with this change. The automaton is the complement of `_type:__*` so it matches
the same documents, but is faster since it is now a positive clause. Simplistic
performance testing on a 10M index where each root document has 5 nested
documents on average gave a latency of 420ms on master and 90ms with this change
applied.
```
"term": {
"foo": {
"value": "0"
}
}
```
This query is rewritten to `+foo:0 #(ConstantScore(+*:* -_type:__*))^0.0` on
master and `foo:0` with this change: we do not need to filter nested docs out
since the query cannot match nested docs. While doing performance testing in
the same conditions as above, response times went from 250ms to 50ms.
```
"nested": {
"path": "nested",
"query": {
"term": {
"nested.foo": {
"value": "0"
}
}
}
}
```
This query is rewritten to
`+ToParentBlockJoinQuery (+nested.foo:0 #_type:__nested) #(ConstantScore(+*:* -_type:__*))^0.0`
on master and `ToParentBlockJoinQuery (nested.foo:0)` with this change. The
top-level filter (`-_type:__*`) could be removed since `nested` queries only
match documents of the parent space, as well as the child filter
(`#_type:__nested`) since the child query may only match nested docs since the
`nested` object has both `include_in_parent` and `include_in_root` set to
`false`. While doing performance testing in the same conditions as above,
response times went from 850ms to 270ms.
I encountered several cases of duplicate field names when generating random
fields using the RandomObjects helper. This leads to invalid json in some tests,
so increasing the minimum field name length to four to make this less likely to
happen.
When Netty decodes a bad HTTP request, it marks the decoder result on
the HTTP request as a failure, and reroutes the request to GET
/bad-request. This either leads to puzzling responses when a bad request
is sent to Elasticsearch (if an index named "bad-request" does not exist
then it produces an index not found exception and otherwise responds
with the index settings for the index named "bad-request"). This commit
addresses this by inspecting the decoder result on the HTTP request and
dispatching the request to a bad request handler preserving the initial
cause of the bad request and providing an error message to the client.
Relates #23153
This commit adds a new method to the TransportChannel that provides access to the version of the
remote node that the response is being sent on and that the request came from. This is helpful
for serialization of data attached as headers.
The traces callback is only called after responses are set. This can lead to concurrent issues where the trace is notified of previously sent responses if it was added after the response was sent (enabling further execution of the test) but before the tracer call backs are called.
EvillPeerRecoveryIT checks scenario where recovery is happening while there are on going indexing operation that already have been assigned a seq# . This is fairly hard to achieve and the test goes through a couple of hoops via the plugin infra to achieve that. This PR extends the unit tests infra to allow for those hoops to happen in unit tests. This allows the test to be moved to RecoveryDuringReplicationTests
Relates to #22484
We have a bunch of interfaces that have only a single implementation
for 6 years now. These interfaces are pretty useless from a SW development
perspective and only add unnecessary abstractions. They also require
lots of casting in many places where we expect that there is only one
concrete implementation. This change removes the interfaces, makes
all of the classes final and removes the duplicate `foo` `getFoo` accessors
in favor of `getFoo` from these classes.
Elasticsearch v5.0.0 uses allocation IDs to safely allocate primary shards whereas prior versions of ES used a version-based mode instead. Elasticsearch v5 still has support for version-based primary shard allocation as it needs to be able to load 2.x shards. ES v6 can drop the legacy support.
#22194 gave us the ability to open low level temporary connections to remote node based on their address. With this use case out of the way, actual full blown connections should validate the node on the other side, making sure we speak to who we think we speak to. This helps in case where multiple nodes are started on the same host and a quick node restart causes them to swap addresses, which in turn can cause confusion down the road.
Secure settings from the elasticsearch keystore were not yet validated.
This changed improves support in Settings so that secure settings more
seamlessly blend in with normal settings, allowing the existing settings
validation to work. Note that the setting names are still not validated
(yet) when using the elasticsearc-keystore tool.
As part of #22116 we are going to forbid usage of api
java.net.URL#openStream(). However in a number of places across the
we use this method to read files from the local filesystem. This commit
introduces a helper method openFileURLStream(URL url) to read files
from URLs. It does specific validation to only ensure that file:/
urls are read.
Additionlly, this commit removes unneeded method
FileSystemUtil.newBufferedReader(URL, Charset). This method used the
openStream () method which will soon be forbidden. Instead we use the
Files.newBufferedReader(Path, Charset).
This is in order to trigger listeners for disconnect events, most importantly the NodeFaultDetection. MockTransportService now does slightly a better job at mimicking real life failures: connecting to already connected node will be a noop (we don't detect any errors here in production either) and failing to send will cause the target node to be disconnected.
This is the cause of failure in https://elasticsearch-ci.elastic.co/job/elastic+elasticsearch+5.2+multijob-unix-compatibility/os=debian/72
When a node receives a new cluster state from the master, it opens up connections to any new node in the cluster state. That has always been done serially on the cluster state thread but it has been a long standing TODO to do this concurrently, which is done by this PR.
This is spin off of #22828, where an extra handshake is done whenever connecting to a node, which may slow down connecting. Also, the handshake is done in a blocking fashion which triggers assertions w.r.t blocking requests on the cluster state thread. Instead of adding an exception, I opted to implement concurrent connections which both side steps the assertion and compensates for the extra handshake.
This commit upgrades the checkstyle configuration from version 5.9 to
version 7.5, the latest version as of today. The main enhancement
obtained via this upgrade is better detection of redundant modifiers.
Relates #22960
This change adds a strict mode for xcontent parsing on the rest layer. The strict mode will be off by default for 5.x and in a separate commit will be enabled by default for 6.0. The strict mode, which can be enabled by setting `http.content_type.required: true` in 5.x, will require that all incoming rest requests have a valid and supported content type header before the request is dispatched. In the non-strict mode, the Content-Type header will be inspected and if it is not present or not valid, we will continue with auto detection of content like we have done previously.
The content type header is parsed to the matching XContentType value with the only exception being for plain text requests. This value is then passed on with the content bytes so that we can reduce the number of places where we need to auto-detect the content type.
As part of this, many transport requests and builders were updated to provide methods that
accepted the XContentType along with the bytes and the methods that would rely on auto-detection have been deprecated.
In the non-strict mode, deprecation warnings are issued whenever a request with body doesn't provide the Content-Type header.
See #19388
This commit change ElasticsearchException.failureFromXContent() method so that it now parses root causes which were ignored before, and adds them as suppressed exceptions of the returned exception.
The seq# base recovery logic relies on rolling back lucene to remove any operations above the global checkpoint. This part of the plan is not implemented yet but have to have these guarantees. Instead we should make the seq# logic validate that the last commit point (and the only one we have) maintains the invariant and if not, fall back to file based recovery.
This commit adds a test that creates situation where rollback is needed (primary failover with ops in flight) and fixes another issue that was surfaced by it - if a primary can't serve a seq# based recovery request and does a file copy, it still used the incoming `startSeqNo` as a filter.
Relates to #22484 & #10708
With the new secure settings, methods like getAsMap() no longer work
correctly as a means of checking for empty settings, or the total size.
This change converts the existing uses of that method to use methods
directly on Settings. Note this does not update the implementations to
account for SecureSettings, as that will require a followup which
changes how secure settings work.
Also adds many `equals` and `hashCode` implementations and moves
the failure printing in `MatchAssertion` into a common spot and
exposes it over `assertEqualsWithErrorMessageFromXContent` which
does an object equality test but then uses `toXContent` to print
the differences.
Relates to #22278
This moves the building blocks for delete by query into core. This
should enabled two thigns:
1. Plugins other than reindex to implement "bulk by scroll" style
operations.
2. Plugins to directly call delete by query. Those plugins should
be careful to make sure that task cancellation still works, but
this should be possible.
Notes:
1. I've mostly just moved classes and moved around tests methods.
2. I haven't been super careful about cohesion between these core
classes and reindex. They are quite interconnected because I wanted
to make the change as mechanical as possible.
Closes#22616
* S3 repository: Add named configurations
This change implements named configurations for s3 repository as
proposed in #22520. The access/secret key secure settings which were
added in #22479 are reverted, and the only secure settings are those
with the new named configs. All other previously used settings for the
connection are deprecated.
closes#22520
Also adds many `equals` and `hashCode` implementations and moves
the failure printing in `MatchAssertion` into a common spot and
exposes it over `assertEqualsWithErrorMessageFromXContent` which
does an object equality test but then uses `toXContent` to print
the differences.
Relates to #22278
This commit introduces sequence-number-based recovery. When a replica
has fallen out of sync, rather than performing a file-based recovery we
first attempt to replay operations since the last local checkpoint on
the replica. To do this, at the start of recovery the replica tells the
primary what its local checkpoint is. The primary will then wait for all
operations between that local checkpoint and the current maximum
sequence number to complete; this is to ensure that there are no gaps in
the operations that will be replayed from the primary to the
replica. This is a best-effort attempt as we currently have no
guarantees on the primary that these operations will be available; if we
are not able to replay all operations in the desired range, we just
fallback to file-based recovery. Later work will strengthen the
guarantees.
Relates #22484
* Add top hits collapsing to search request
The field collapsing is done with a custom top docs collector that "collapse" search hits with same field value.
The distributed aspect is resolve using the two passes that the regular search uses. The first pass "collapse" the top hits, then the coordinating node merge/collapse the top hits from each shard.
```
GET _search
{
"collapse": {
"field": "category",
}
}
```
This change also adds an ExpandCollapseSearchResponseListener that intercepts the search response and expands collapsed hits using the CollapseBuilder#innerHit} options.
The retrieval of each inner_hits is done by sending a query to all shards filtered by the collapse key.
```
GET _search
{
"collapse": {
"field": "category",
"inner_hits": {
"size": 2
}
}
}
```
To effectively allow a plugin to intercept a transport handler it needs
to know if the handler must be executed even if there is a rejection on the
thread pool in the case the wrapper forks a thread to execute the actual handler.
Today we try to be smart and make a generic decision if an exception should
be treated as a document failure but in some cases concurrency in the index writer
make this decision very difficult since we don't have a consistent state in the case
another thread is currently failing the IndexWriter/InternalEngine due to a tragic event.
This change simplifies the exception handling and makes specific decisions about document failures
rather than using a generic heuristic. This prevent exceptions to be treated as document failures
that should have failed the engine but backed out of failing since since some other thread has
already taken over the failure procedure but didn't finish yet.
* S3 repository: Deprecate specifying credentials through env vars and sys props
This is a follow up to #22479, where storing credentials secure way was
added.
Today we do not preserve response headers if they are present on a transport protocol
response. While preserving these headers is not always desired, in the most cases we
should pass on these headers to have consistent results for depreciation headers etc.
yet, this hasn't been much of a problem since most of the deprecations are detected early
ie. on the coordinating node such that this bug wasn't uncovered until #22647
This commit allow to optionally preserve headers when a context is restored and also streamlines
the context restore since it leaked frequently into the callers thread context when the callers
context wasn't restored again.
Previously, certain settings that could take multiple comma delimited
values would pick up incorrect values for all entries but the first if
each comma separated value was followed by a whitespace character. For
example, the multi-value "A,B,C" would be correctly parsed as
["A", "B", "C"] but the multi-value "A, B, C" would be incorrectly parsed
as ["A", " B", " C"].
This commit allows a comma separated list to have whitespace characters
after each entry. The specific settings that were affected by this are:
cluster.routing.allocation.awareness.attributes
index.routing.allocation.require.*
index.routing.allocation.include.*
index.routing.allocation.exclude.*
cluster.routing.allocation.require.*
cluster.routing.allocation.include.*
cluster.routing.allocation.exclude.*
http.cors.allow-methods
http.cors.allow-headers
For the allocation filtering related settings, this commit also provides
validation of each specified entry if the filtering is done by _ip,
_host_ip, or _publish_ip, to ensure that each entry is a valid IP
address.
Closes#22297
Today we have quite some abstractions that are essentially providing a simple
dispatch method to the plugins defining a `HttpServerTransport`. This commit
removes `HttpServer` and `HttpServerAdaptor` and introduces a simple `Dispatcher` functional
interface that delegate to `RestController` by default.
Relates to #18482
All the language clients support a special ignore parameter that doesn't get passed to elasticsearch with the request, but used to indicate which error code should not lead to an exception if returned for a specific request.
Moving this to the low level REST client will allow the high level REST client to make use of it too, for instance so that it doesn't have to intercept ResponseExceptions when the get api returns a 404.
TransportInterceptors are commonly used to enrich requests with headers etc.
which requires access the the thread context. This is not always easily possible
since threadpools are hard to access for instance if the interceptor is used on a transport client.
This commit passes on the thread context to all the interceptors for further consumption.
Closes#22585
ClusterService and TransportService expect the local discovery node to be set
before they are started but this requires manual interaction and is error prone since
to work absolutely correct they should share the same instance (same ephemeral ID).
TransportService also has 2 modes of operation, mainly realted to transport client vs. internal
to a node. This change removes the mode where we don't maintain a local node and uses a dummy local
node in the transport client since we don't bind to any port in such a case.
Local discovery node instances are now managed by the node itself and only suppliers and factories that allow
creation only once are passed to TransportService and ClusterService.
There was still small race in MockTcpTransport where channesl that are concurrently
closing are not yet removed from the reference tracking causing tests to fail. Compared to
the other races before this is a rather small windown and requires very very short test durations.
Today there are several races / holes in TcpTransport and MockTcpTransport
that can allow connections to be opened and remain unclosed while the actual
transport implementation is closed. A recently added assertions in #22554 exposes
these problems. This commit fixes several issues related to missed locks or channel
creations outside of a lock not checking if the resource is still open.
There are some parameters that are accepted by each and every api we expose. Those (pretty, source, error_trace and filter_path) are not explicitly listed in the spec of every api, rather whitelisted in clients test runners so that they are always accepted. The `human` flag has been treated up until now as a parameter that's accepted by only some stats and info api, but that doesn't reflect reality as es core treats it exactly like `pretty` (relevant especially now that we validate params and throw exception when we find one that is not supported). Furthermore, the human flag has effect on every api that outputs a date, time, percentage or byte size field. For instance the tasks api outputs a date field although they don't have the human flag explicitly listed in their spec. There are other similar cases. This commit removes the human flag from the rest spec and makes it an always accepted query_string param.
TcpTransport has an actual mechanism to stop resources in subclasses.
Instead of overriding `doStop` subclasses should override `stopInternal`
that is executed under the connection lock guaranteeing that there is no
concurrency etc.
Relates to #22554
* Settings: Make s3 repository sensitive settings use secure settings
This change converts repository-s3 to use the new secure settings. In
order to support the multiple ways we allow aws creds to be configured,
it also moves the main methods for the keystore wrapper into a
SecureSettings interface, in order to allow settings prefixing to work.
The low level TCP handshake can cause channel / connection leaks if it's interrupted
since the caller doesn't close the channel / connection if the handshake was not successful.
This commit fixes the channel leak and adds general test infrastructure to detect channel leaks
in the future.
This commit adds the parsing fromXContent() methods to the IndexResponse class. The method is based on a ObjectParser because it is easier to use when parsing parent abstract classes like DocWriteResponse.
It also changes the ReplicationResponse.ShardInfo so that it now implements ToXContentObject. This way, the ShardInfo.fromXContent() method can be used by the IndexResponse's ObjectParser.
The NodeConnectionsService currently determines which nodes to connect to / disconnect from by inspecting cluster state changes and connecting to added nodes / disconnecting from removed nodes. When a master steps down (for example due to another master-eligible node shutting down which brings the number of master-eligible nodes below minimum_master_master), and the connection to other existing nodes was dropped while pinging, however, the connection to these nodes is not re-established while publishing the first cluster state that establishes the node as master.
This commit changes the NodeConnectionsService connect / disconnect logic to always rely on the state that is to be / was published, looking not only at the added / removed nodes, but validating that exactly all nodes that are currently registered in NodeConnectionsService are connected (corresponds to a NOOP if the node is already connected).
Right now closing a shard looks like it strands refresh listeners,
causing tests like
`delete/50_refresh/refresh=wait_for waits until changes are visible in search`
to fail. Here is a build that fails:
https://elasticsearch-ci.elastic.co/job/elastic+elasticsearch+multi_cluster_search+multijob-darwin-compatibility/4/console
This attempts to fix the problem by implements `Closeable` on
`RefreshListeners` and rejecting listeners when closed. More importantly
the act of closing the instance flushes all pending listeners
so we shouldn't have any stranded listeners on close.
Because it was needed for testing, this also adds the number of
pending listeners to the `CommonStats` object and all API to which
that flows: `_cat/nodes`, `_cat/indices`, `_cat/shards`, and
`_nodes/stats`.
This is related to #22116. A logIfNecessary() call makes a call to
NetworkInterface.getInterfaceAddresses() requiring SocketPermission
connect privileges. By moving this to bootstrap the logging call can be
made before installing the SecurityManager.
Today we execute the low level handshake on the TCP layer in #connectToNode.
If #openConnection is used directly, which is truly expert, no handshake is executed
which allows connecting to nodes that are not necessarily compatible. This change
moves the handshake to #openConnection to prevent bypassing this logic.
This integrates the mocksocket jar with elasticsearch tests. Mocksocket wraps actions requiring SocketPermissions in doPrivilege blocks. This will eventually allow SocketPermissions to be assigned to the mocksocket jar opposed to the entire elasticsearch codebase.
Notifications for request tracing are invoked concurrently and can still
be in flight once a tracer is installed in the test. This can lead to side-effects
since the test relied on exact invocations. This commit adds action filtering
to the test tracer to only count invocations for the relevant actions.
Closes#22418
this commit adds full support for proxy nodes on the search layer.
This allows to connection only to a small set of nodes on a remote cluster
to exectue the search. The nodes will proxy the request to the correct node in the
cluster while the coordinting node doesn't need to be connected to the target node.
There could be an issue creating the REST clients and/or making the first request to the external cluster. If that happens, the blacklist has already been assigned and the following tests will fail because of an assertion that checks that the blacklist is not already assigned when the contexts are not.
Today we silently ignore invalid test logging annotations. This commit
rejects these annotations, failing the processing of the annotation and
aborting the test.
This commit adds a test for applying logging levels in hierarchical
order, and addresses an issue with restoring the logging levels at the
end of a test or suite.
This commit factors out the cluster state update tasks that are published (ClusterStateUpdateTask) from those that are not (LocalClusterUpdateTask), serving as a basis for future refactorings to separate the publishing mechanism out of ClusterService.
We have to sort the logger names so they wouldn't override each other. Processing org.elasticsearch:DEBUG after org.elasticsearch.transport:TRACE resets the setting of the later
This change is the first towards providing the ability to store
sensitive settings in elasticsearch. It adds the
`elasticsearch-keystore` tool, which allows managing a java keystore.
The keystore is loaded upon node startup in Elasticsearch, and used by
the Setting infrastructure when a setting is configured as secure.
There are a lot of caveats to this PR. The most important is it only
provides the tool and setting infrastructure for secure strings. It does
not yet provide for keystore passwords, keypairs, certificates, or even
convert any existing string settings to secure string settings. Those
will all come in follow up PRs. But this PR was already too big, so this
at least gets a basic version of the infrastructure in.
The two main things to look at. The first is the `SecureSetting` class,
which extends `Setting`, but removes the assumption for the raw value of the
setting to be a string. SecureSetting provides, for now, a single
helper, `stringSetting()` to create a SecureSetting which will return a
SecureString (which is like String, but is closeable, so that the
underlying character array can be cleared). The second is the
`KeyStoreWrapper` class, which wraps the java `KeyStore` to provide a
simpler api (we do not need the entire keystore api) and also extend
the serialized format to add metadata needed for loading the keystore
with no assumptions about keystore type (so that we can change this in
the future) as well as whether the keystore has a password (so that we
can know whether prompting is necessary when we add support for keystore
passwords).
* Remove a checked exception, replacing it with `ParsingException`.
* Remove all Parser classes for the yaml sections, replacing them with static methods.
* Remove `ClientYamlTestFragmentParser`. Isn't used any more.
* Remove `ClientYamlTestSuiteParseContext`, replacing it with some static utility methods.
I did not rewrite the parsers using `ObjectParser` because I don't think it is worth it right now.
This adds test classes that can be used to test the wire serialisation and (optionally) the XContent serialisation of objects that implement Streamable/Writeable and ToXContent.
These test classes will enable classes sich as InternalAggregation (or at least its implementations) to be tested in a consistent way when is comes to testing serialisation.
As the translog evolves towards a full operations log as part of the
sequence numbers push, there is a need for the translog to be able to
represent operations for which a sequence number was assigned, but the
operation did not mutate the index. Examples of how this can arise are
operations that fail after the sequence number is assigned, and gaps in
this history that arise when an operation is assigned a sequence number
but the operation never completed (e.g., a node crash). It is important
that these operations appear in the history so that they can be
replicated and replayed during recovery as otherwise the history will be
incomplete and local checkpoints will not be able to advance. This
commit introduces a no-op to the translog to set the stage for these
efforts.
Relates #22291
The `UnicastZenPing` shows it's age and is the result of many small changes. The current state of affairs is confusing and is hard to reason about. This PR cleans it up (while following the same original intentions). Highlights of the changes are:
1) Clear 3 round flow - no interleaving of scheduling.
2) The previous implementation did a best effort attempt to wait for ongoing pings to be sent and completed. The pings were guaranteed to complete because each used the total ping duration as a timeout. This did make it hard to reason about the total ping duration and the flow of the code. All of this is removed now and ping should just complete within the given duration or not be counted (note that it was very handy for testing, but I move the needed sync logic to the test).
3) Because of (2) the pinging scheduling changed a bit, to give a chance for the last round to complete. We now ping at the beginning, 1/3 and 2/3 of the duration.
4) To offset for (3) a bit, incoming ping requests are now added to on going ping collections.
5) UnicastZenPing never establishes full blown connections (but does reuse them if there). Relates to #22120
6) Discovery host providers are only used once per pinging round. Closes#21739
7) Usage of the ability to open a connection without connecting to a node ( #22194 ) and shorter connection timeouts helps with connections piling up. Closes#19370
8) Beefed up testing and sped them up.
9) removed light profile from production code
If we conditionally do random things, e.g. initialize a node only after the first test, we have to make sure that we unconditionally create a new seed calling random.nextLong(), then initialize the node under a private randomness context. This makes sure that any random usage through Randomness.get() will retrieve the proper random instance through RandomizedContext.current().getRandom(). When running under private randomness, the context will return the Random instance that was created with the provided seed (forked from the main random instance) rather than the main Random that's exposed to tests as well. Otherwise tests become non repeatable because that initialization part happens only before the first executed test.