Since the removal of local discovery of #https://github.com/elastic/elasticsearch/pull/20960 we rely on minimum master nodes to be set in our test cluster. The settings is automatically managed by the cluster (by default) but current management doesn't work with concurrent single node async starting. On the other hand, with `MockZenPing` and the `discovery.initial_state_timeout` set to `0s` node starting and joining is very fast making async starting an unneeded complexity. Test that still need async starting could, in theory, still do so themselves via background threads.
Note that this change also removes the usage of `INITIAL_STATE_TIMEOUT_SETTINGS` as the starting of nodes is done concurrently (but building them is sequential)
Today we eagerly resolve unicast hosts. This means that if DNS changes,
we will never find the host at the new address. Moreover, a single host
failng to resolve causes startup to abort. This commit introduces lazy
resolution of unicast hosts. If a DNS entry changes, there is an
opportunity for the host to be discovered. Note that under the Java
security manager, there is a default positive cache of infinity for
resolved hosts; this means that if a user does want to operate in an
environment where DNS can change, they must adjust
networkaddress.cache.ttl in their security policy. And if a host fails
to resolve, we warn log the hostname but continue pinging other
configured hosts.
When doing DNS resolutions for unicast hostnames, we wait until the DNS
lookups timeout. This appears to be forty-five seconds on modern JVMs,
and it is not configurable. If we do these serially, the cluster can be
blocked during ping for a lengthy period of time. This commit introduces
doing the DNS lookups in parallel, and adds a user-configurable timeout
for these lookups.
Relates #21630
#20960 removed `LocalDiscovery` and we now use `ZenDiscovery` in all our tests. To keep cluster forming fast, we are using a `MockZenPing` implementation which uses static maps to return instant results making master election fast. Currently, we don't set `minimum_master_nodes` causing the occasional split brain when starting multiple nodes concurrently and their pinging is so fast that it misses the fact that one of the node has elected it self master. To solve this, `InternalTestCluster` is modified to behave like a true cluster and manage and set `minimum_master_nodes` correctly with every change to the number of nodes.
Tests that want to manage the settings themselves can opt out using a new `autoMinMasterNodes` parameter to the `ClusterScope` annotation.
Having `min_master_nodes` set means the started node may need to wait for other nodes to be started as well. To combat this, we set `discovery.initial_state_timeout` to `0` and wait for the cluster to form once all node have been started. Also, because a node may wait and ping while other nodes are started, `MockZenPing` is adapted to wait rather than busy-ping.
This changes adds a test discovery (which internally uses the existing
mock zenping by default). Having the mock the test framework selects be a discovery
greatly simplifies discovery setup (no more weird callback to a Node
method).
* Plugins: Convert custom discovery to pull based plugin
This change primarily moves registering custom Discovery implementations
to the pull based DiscoveryPlugin interface. It also keeps the cloud
based discovery plugins re-registering ZenDiscovery under their own name
in order to maintain backwards compatibility. However,
discovery.zen.hosts_provider is changed here to no longer fallback to
discovery.type. Instead, each plugin which previously relied on the
value of discovery.type now sets the hosts_provider to itself if
discovery.type is set to itself, along with a deprecation warning.
At one point in the past when moving out the rest tests from core to
their own subproject, we had multiple test classes which evenly split up
the tests to run. However, we simplified this and went back to a single
test runner to have better reproduceability in tests. This change
removes the remnants of that multiplexing support.
Follow up for #21039.
We can revert the previous change and do that a bit smarter than it was.
Patch tested successfully manually on ec2 with 2 nodes with a configuration like:
```yml
discovery.type: ec2
network.host: ["_local_", "_site_", "_ec2_"]
cloud.aws.region: us-west-2
```
(cherry picked from commit fbbeded)
Backport of #21048 in master branch
This change moves providing UnicastHostsProvider for zen discovery to be
pull based, adding a getter in DiscoveryPlugin. A new setting is added,
discovery.zen.hosts_provider, to separate the discovery type from the
hosts provider for zen when it is selected. Unfortunately existing
plugins added ZenDiscovery with their own name in order to just provide
a hosts provider, so there are already many users setting the hosts
provider through discovery.type. This change also includes backcompat,
falling back to discovery.type when discovery.zen.hosts_provider is not
set.
Here is what is happening without this fix when you try to connect to ec2 APIs:
```
[2016-10-20T12:41:49,925][DEBUG][c.a.a.AWSCredentialsProviderChain] Unable to load credentials from EnvironmentVariableCredentialsProvider: Unable to load AWS credentials from environment variables (AWS_ACCESS_KEY_ID (or AWS_ACCESS_KEY) and AWS_SECRET_KEY (or AWS_SECRET_ACCESS_KEY))
[2016-10-20T12:41:49,926][DEBUG][c.a.a.AWSCredentialsProviderChain] Unable to load credentials from SystemPropertiesCredentialsProvider: Unable to load AWS credentials from Java system properties (aws.accessKeyId and aws.secretKey)
[2016-10-20T12:41:49,926][DEBUG][c.a.a.AWSCredentialsProviderChain] Unable to load credentials from com.amazonaws.auth.profile.ProfileCredentialsProvider@1ad14091: access denied ("java.io.FilePermission" "/home/ubuntu/.aws/credentials" "read")
[2016-10-20T12:41:49,927][DEBUG][c.a.i.EC2MetadataClient ] Connecting to EC2 instance metadata service at URL: http://169.254.169.254/latest/meta-data/iam/security-credentials/
[2016-10-20T12:41:49,951][DEBUG][c.a.i.EC2MetadataClient ] Connecting to EC2 instance metadata service at URL: http://169.254.169.254/latest/meta-data/iam/security-credentials/discovery-tests
[2016-10-20T12:41:49,965][DEBUG][c.a.a.AWSCredentialsProviderChain] Unable to load credentials from InstanceProfileCredentialsProvider: Unable to parse Json String.
[2016-10-20T12:41:49,966][INFO ][o.e.d.e.AwsEc2UnicastHostsProvider] [dJfktmE] Exception while retrieving instance list from AWS API: Unable to load AWS credentials from any provider in the chain
[2016-10-20T12:41:49,967][DEBUG][o.e.d.e.AwsEc2UnicastHostsProvider] [dJfktmE] Full exception:
com.amazonaws.AmazonClientException: Unable to load AWS credentials from any provider in the chain
at com.amazonaws.auth.AWSCredentialsProviderChain.getCredentials(AWSCredentialsProviderChain.java:131) ~[aws-java-sdk-core-1.10.69.jar:?]
at com.amazonaws.services.ec2.AmazonEC2Client.invoke(AmazonEC2Client.java:11117) ~[aws-java-sdk-ec2-1.10.69.jar:?]
at com.amazonaws.services.ec2.AmazonEC2Client.describeInstances(AmazonEC2Client.java:5403) ~[aws-java-sdk-ec2-1.10.69.jar:?]
at org.elasticsearch.discovery.ec2.AwsEc2UnicastHostsProvider.fetchDynamicNodes(AwsEc2UnicastHostsProvider.java:116) [discovery-ec2-5.0.0.jar:5.0.0]
at org.elasticsearch.discovery.ec2.AwsEc2UnicastHostsProvider$DiscoNodesCache.refresh(AwsEc2UnicastHostsProvider.java:234) [discovery-ec2-5.0.0.jar:5.0.0]
at org.elasticsearch.discovery.ec2.AwsEc2UnicastHostsProvider$DiscoNodesCache.refresh(AwsEc2UnicastHostsProvider.java:219) [discovery-ec2-5.0.0.jar:5.0.0]
at org.elasticsearch.common.util.SingleObjectCache.getOrRefresh(SingleObjectCache.java:54) [elasticsearch-5.0.0.jar:5.0.0]
at org.elasticsearch.discovery.ec2.AwsEc2UnicastHostsProvider.buildDynamicNodes(AwsEc2UnicastHostsProvider.java:102) [discovery-ec2-5.0.0.jar:5.0.0]
at org.elasticsearch.discovery.zen.ping.unicast.UnicastZenPing.sendPings(UnicastZenPing.java:358) [elasticsearch-5.0.0.jar:5.0.0]
at org.elasticsearch.discovery.zen.ping.unicast.UnicastZenPing$1.doRun(UnicastZenPing.java:272) [elasticsearch-5.0.0.jar:5.0.0]
at org.elasticsearch.common.util.concurrent.ThreadContext$ContextPreservingAbstractRunnable.doRun(ThreadContext.java:504) [elasticsearch-5.0.0.jar:5.0.0]
at org.elasticsearch.common.util.concurrent.AbstractRunnable.run(AbstractRunnable.java:37) [elasticsearch-5.0.0.jar:5.0.0]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) [?:1.8.0_91]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) [?:1.8.0_91]
at java.lang.Thread.run(Thread.java:745) [?:1.8.0_91]
```
For whatever reason, it can not parse what is coming back from http://169.254.169.254/latest/meta-data/iam/security-credentials/discovery-tests.
But, if you wrap the code within an `AccessController.doPrivileged()` call, then it works perfectly.
Closes#21039.
(cherry picked from commit abfdc70)
* Move all zen discovery classes into o.e.discovery.zen
This collapses sub packages of zen into zen. These all had just a couple
classes each, and there is really no reason to have the subpackages.
* fix checkstyle
UpdateHelper, MetaDataIndexUpgradeService, and some recovery
stuff.
Move ClusterSettings to nullable ctor parameter of TransportService
so it isn't forgotten.
This change proposes the removal of all non-tcp transport implementations. The
mock transport can be used by default to run tests instead of local transport that has
roughly the same performance compared to TCP or at least not noticeably slower.
This is a master only change, deprecation notice in 5.x will be committed as a
separate change.
Because of security permissions that we do not grant to the AWS SDK (for
use in discovery-ec2 and repository-s3 plugins), certain calls in the
AWS SDK will lead to security exceptions that are logged at the warning
level. These warnings are noise and we should suppress them. This commit
adds plugin log configurations for discovery-ec2 and repository-s3 to
ship with default Log4j 2 configurations that suppress these log
warnings.
Relates #20313
This commit modifies the call sites that allocate a parameterized
message to use a supplier so that allocations are avoided unless the log
level is fine enough to emit the corresponding log message.
This makes it obvious that these tests are for running the client yaml
suites. Now that there are other ways of running tests using the REST
client against a running cluster we can't go on calling the shared
client yaml tests "REST tests". They are rest tests, but they aren't
**the** rest tests.
This adds a header that looks like `Location: /test/test/1` to the
response for the index/create/update API. The requirement for the header
comes from https://www.w3.org/Protocols/rfc2616/rfc2616-sec10.htmlhttps://tools.ietf.org/html/rfc7231#section-7.1.2 claims that relative
URIs are OK. So we use an absolute path which should resolve to the
appropriate location.
Closes#19079
This makes large changes to our rest test infrastructure, allowing us
to write junit tests that test a running cluster via the rest client.
It does this by splitting ESRestTestCase into two classes:
* ESRestTestCase is the superclass of all tests that use the rest client
to interact with a running cluster.
* ESClientYamlSuiteTestCase is the superclass of all tests that use the
rest client to run the yaml tests. These tests are shared across all
official clients, thus the `ClientYamlSuite` part of the name.
Follow up for #18662
We add some tests to check that settings are correctly applied.
Tests revealed that some checks were missing.
But we ignore `testAWSCredentialsWithSystemProviders` test for now.
Some tests still start http implicitly or miss configuring the transport clients correctly.
This commit fixes all remaining tests and adds a depdenceny to `transport-netty` from
`qa/smoke-test-http` and `modules/reindex` since they need an http server running on the nodes.
This also moves all required permissions for netty into it's module and out of core.
This change adds a createComponents() method to Plugin implementations
which they can use to return already constructed componenents/services.
Eventually this should be just services ("components" don't really do
anything), but for now it allows any object so that preconstructed
instances by plugins can still be bound to guice. Over time we should
add basic services as arguments to this method, but for now I have left
it empty so as to not presume what is a necessary service.
The DiscoveryNodeService exists to register CustomNodeAttributes which
plugins can add. This is not necessary, since plugins can already add
additional attributes, and use the node attributes prefix.
This change removes the DiscoveryNodeService, and converts the only
consumer, the ec2 discovery plugin, to add the ec2 availability zone
in additionalSettings().
The only reason for LifecycleComponent taking a generic type was so that
it could return that type on its start and stop methods. However, this
chaining has no practical necessity. Instead, start and stop can be
void, and a whole bunch of confusing generics disappear.
We pretended to be able to ackt like a different version node for so long it's
time to be honest and remove this ability. It's just confusing and where needed
and tested we should build dedicated extension points.
This change removes some unnecessary dependencies from ClusterService
and cleans up ClusterName creation. ClusterService is now not created
by guice anymore.
Today we have a push model for registering basically anything. All our extension points
are defined on modules which we pass in to plugins. This is harder to maintain and adds
unnecessary dependencies on the modules itself. This change moves towards a pull model
where the plugin offers a getter kind of method to get the extensions. This will also
help in the future if we need to pass dependencies to the extension points which can
easily be defined on the method as arguments if a pull model is used.
In 2.0 we added plugin descriptors which require defining a name and
description for the plugin. However, we still have name() and
description() which must be overriden from the Plugin class. This still
exists for classpath plugins. But classpath plugins are mainly for
tests, and even then, referring to classpath plugins with their class is
a better idea. This change removes name() and description(), replacing
the name for classpath plugins with the full class name.
This commit refactors the handling of thread pool settings so that the
individual settings can be registered rather than registering the top
level group. With this refactoring, individual plugins must now register
their own settings for custom thread pools that they need, but a
dedicated API is provided for this in the thread pool module. This
commit also renames the prefix on the thread pool settings from
"threadpool" to "thread_pool". This enables a hard break on the settings
so that:
- some of the settings can be given more sensible names (e.g., the max
number of threads in a scaling thread pool is now named "max" instead
of "size")
- change the soft limit on the number of threads in the bulk and
indexing thread pools to a hard limit
- the settings names for custom plugins for thread pools can be
prefixed (e.g., "xpack.watcher.thread_pool.size")
- remove dynamic thread pool settings
Relates #18674
* master: (911 commits)
[TEST] wait for yellow after setup doc tests (#18726)
Fix recovery throttling to properly handle relocating non-primary shards (#18701)
Fix merge stats rendering in RestIndicesAction (#18720)
[TEST] mute RandomAllocationDeciderTests.testRandomDecisions
Reworked docs for index-shrink API (#18705)
Improve painless compile-time exceptions
Adds UUIDs to snapshots
Add test rethrottle test case for delete-by-query
Do not start scheduled pings until transport start
Adressing review comments
Only filter intial recovery (post API) when shrinking an index (#18661)
Add tests to check that toQuery() doesn't return null
Removing handling of null lucene query where we catch this at parse time
Handle empty query bodies at parse time and remove EmptyQueryBuilder
Mute failing assertions in IndexWithShadowReplicasIT until fix
Remove allow running as root
Add upgrade-not-supported warning to alpha release notes
remove unrecognized javadoc tag from matrix aggregation module
set ValuesSourceConfig fields as private
Adding MultiValuesSource support classes and documentation to matrix stats agg module
...
This PR changes the InternalTestCluster to support dedicated master nodes. The creation of dedicated master nodes can be controlled using a new `supportsMasterNodes` parameter to the ClusterScope annotation. If set to true (the default), dedicated master nodes will randomly be used. If set to false, no master nodes will be created and data nodes will also be allowed to become masters. If active, test runs will either have 1 or 3 masternodes
I am unable to set ec2 discovery tags because this setting was
accidentally omitted from the register settings list in
Ec2DiscoveryPlugin.java. I get this:
java.lang.IllegalArgumentException: unknown setting [discovery.ec2.tag.project]
This commit introduces a handshake when initiating a light
connection. During this handshake, node information, cluster name, and
version are received from the target node of the connection. This
information can be used to immediately validate that the target node is
a member of the same cluster, and used to set the version on the
stream. This will allow us to extend APIs that are used during initial
cluster recovery without a major version change.
Relates #15971
* Moving from JSON.org to Jackson for request marshallers.
* The Java SDK now supports retry throttling to limit the rate of retries during periods of reduced availability. This throttling behavior can be enabled via ClientConfiguration or via the system property "-Dcom.amazonaws.sdk.enableThrottledRetry".
* Fixed String case conversion issues when running with non English locales.
* AWS SDK for Java introduces a new dynamic endpoint system that can compute endpoints for services in new regions.
* Introducing a new AWS region, ap-northeast-2.
* Added a new metric, HttpSocketReadTime, that records socket read latency. You can enable this metric by adding enableHttpSocketReadMetric to the system property com.amazonaws.sdk.enableDefaultMetrics. For more information, see [Enabling Metrics with the AWS SDK for Java](https://java.awsblog.com/post/Tx3C0RV4NRRBKTG/Enabling-Metrics-with-the-AWS-SDK-for-Java).
* New Client Execution timeout feature to set a limit spent across retries, backoffs, ummarshalling, etc. This new timeout can be specified at the client level or per request.
Also included in this release is the ability to specify the existing HTTP Request timeout per request rather than just per client.
* Added support for RequesterPays for all operations.
* Ignore the 'Connection' header when generating S3 responses.
* Allow users to generate an AmazonS3URI from a string without using URL encoding.
* Fixed issue that prevented creating buckets when using a client configured for the s3-external-1 endpoint.
* Amazon S3 bucket lifecycle configuration supports two new features: the removal of expired object delete markers and an action to abort incomplete multipart uploads.
* Allow TransferManagerConfiguration to accept integer values for multipart upload threshold.
* Copy the list of ETags before sorting https://github.com/aws/aws-sdk-java/pull/589.
* Option to disable chunked encoding https://github.com/aws/aws-sdk-java/pull/586.
* Adding retry on InternalErrors in CompleteMultipartUpload operation. https://github.com/aws/aws-sdk-java/issues/538
* Deprecated two APIs : AmazonS3#changeObjectStorageClass and AmazonS3#setObjectRedirectLocation.
* Added support for the aws-exec-read canned ACL. Owner gets FULL_CONTROL. Amazon EC2 gets READ access to GET an Amazon Machine Image (AMI) bundle from Amazon S3.
* Added support for referencing security groups in peered Virtual Private Clouds (VPCs). For more information see the service announcement at https://aws.amazon.com/about-aws/whats-new/2016/03/announcing-support-for-security-group-references-in-a-peered-vpc/ .
* Fixed a bug in AWS SDK for Java - Amazon EC2 module that returns NPE for dry run requests.
* Regenerated client with new implementation of code generator.
* This feature enables support for DNS resolution of public hostnames to private IP addresses when queried over ClassicLink. Additionally, you can now access private hosted zones associated with your VPC from a linked EC2-Classic instance. ClassicLink DNS support makes it easier for EC2-Classic instances to communicate with VPC resources using public DNS hostnames.
* You can now use Network Address Translation (NAT) Gateway, a highly available AWS managed service that makes it easy to connect to the Internet from instances within a private subnet in an AWS Virtual Private Cloud (VPC). Previously, you needed to launch a NAT instance to enable NAT for instances in a private subnet. Amazon VPC NAT Gateway is available in the US East (N. Virginia), US West (Oregon), US West (N. California), EU (Ireland), Asia Pacific (Tokyo), Asia Pacific (Singapore), and Asia Pacific (Sydney) regions. To learn more about Amazon VPC NAT, see [New - Managed NAT (Network Address Translation) Gateway for AWS](https://aws.amazon.com/blogs/aws/new-managed-nat-network-address-translation-gateway-for-aws/)
* A default read timeout is now applied when querying data from EC2 metadata service.
We have both `Settings.settingsBuilder` and `Settings.builder` that do exactly
the same thing, so we should keep only one. I kept `Settings.builder` since it
has my preference but also it is the one that we use in examples of the Java API.
Node roles are now serialized as well, they are not part of the node attributes anymore. DiscoveryNodeService takes care of dividing settings into attributes and roles. DiscoveryNode always requires to pass in attributes and roles separately.
This change moves placeholder replacement to a pkg private class for
settings. It also adds a null check when calling replacement, as
settings objects can still contain null values, because we only prohibit
nulls on file loading. Finally, this cleans up file and stream loading a
bit to not have unnecessary exception wrapping.
DiscoveryService was a bridge into the discovery universe. This is unneeded and we can just access discovery directly or do things in a different way.
One of those different ways, is not having a dedicated discovery implementation for each our dicovery plugins but rather reuse ZenDiscovery.
UnicastHostProviders are now classified by discovery type, removing unneeded checks on plugins.
Closes#16821
Instead of modifying methods each time we need to add a new behavior for settings, we can simply pass `SettingsProperty... properties` instead.
`SettingsProperty` could be defined then:
```
public enum SettingsProperty {
Filtered,
Dynamic,
ClusterScope,
NodeScope,
IndexScope
// HereGoesYours;
}
```
Then in setting code, it become much more flexible.
TODO: Note that we need to validate SettingsProperty which are added to a Setting as some of them might be mutually exclusive.
Now we have a nice Setting infra, we can define in Setting class if a setting should be filtered or not.
So when we register a setting, setting filtering would be automatically done.
Instead of writing:
```java
Setting<String> KEY_SETTING = Setting.simpleString("cloud.aws.access_key", false, Setting.Scope.CLUSTER);
settingsModule.registerSetting(AwsEc2Service.KEY_SETTING, false);
settingsModule.registerSettingsFilterIfMissing(AwsEc2Service.KEY_SETTING.getKey());
```
We could simply write:
```java
Setting<String> KEY_SETTING = Setting.simpleString("cloud.aws.access_key", false, Setting.Scope.CLUSTER, true);
settingsModule.registerSettingsFilterIfMissing(AwsEc2Service.KEY_SETTING.getKey());
```
It also removes `settingsModule.registerSettingsFilterIfMissing` method.
The plan would be to remove as well `settingsModule.registerSettingsFilter` method but it still used with wildcards. For example in Azure Repository plugin:
```java
module.registerSettingsFilter(AzureStorageService.Storage.PREFIX + "*.account");
module.registerSettingsFilter(AzureStorageService.Storage.PREFIX + "*.key");
```
Closes#16598.
# Please enter a commit message to explain why this merge is necessary,
# especially if it merges an updated upstream into a topic branch.
#
# Lines starting with '#' will be ignored, and an empty message aborts
# the commit.
The rest test framework, because it used to be tightly integrated with
ESIntegTestCase, currently expects the addresses for the test cluster to
be passed using the transport protocol port. However, it only uses this
to then find the http address.
This change makes ESRestTestCase extend from ESTestCase instead of
ESIntegTestCase, and changes the sysprop used to tests.rest.cluster,
which now takes the http address.
closes#15459
Site plugins used to be used for things like kibana and marvel, but
there is no longer a need since kibana (and marvel as a kibana plugin)
uses node.js. This change removes site plugins, as well as the flag for
jvm plugins. Now all plugins are jvm plugins.
This fixes the `lenient` parameter to be `missingClasses`. I will remove this boolean and we can handle them via the normal whitelist.
It also adds a check for sheisty classes (jar hell with the jdk).
This is inspired by the lucene "sheisty" classes check, but it has false positives. This check is more evil, it validates every class file against the extension classloader as a resource, to see if it exists there. If so: jar hell.
This jar hell is a problem for several reasons:
1. causes insanely-hard-to-debug problems (like bugs in forbidden-apis)
2. hides problems (like internal api access)
3. the code you think is executing, is not really executing
4. security permissions are not what you think they are
5. brings in unnecessary dependencies
6. its jar hell
The more difficult problems are stuff like jython, where these classes are simply 'uberjared' directly in, so you cant just fix them by removing a bogus dependency. And there is a legit reason for them to do that, they want to support java 1.4.
This commit removes and now forbids all uses of
Collections#shuffle(List) and Random#<init>() across the codebase. The
rationale for removing and forbidding these methods is to increase test
reproducibility. As these methods use non-reproducible seeds, production
code and tests that rely on these methods contribute to
non-reproducbility of tests.
Instead of Collections#shuffle(List) the method
Collections#shuffle(List, Random) can be used. All that is required then
is a reproducible source of randomness. Consequently, the utility class
Randomness has been added to assist in creating reproducible sources of
randomness.
Instead of Random#<init>(), Random#<init>(long) with a reproducible seed
or the aforementioned Randomess class can be used.
Closes#15287
This commit adds the infrastructure to make settings that are updateable
resetable and changes the application of updates to be transactional. This means
setting updates are either applied or not. If the application failes all values are rejected.
This initial commit converts all dynamic cluster settings to make use of the new infrastructure.
All cluster level dynamic settings are not resettable to their defaults or to the node level settings.
The infrastructure also allows to list default values and descriptions which is not fully implemented yet.
Values can be reset using a list of key or simple regular expressions. This has only been implemented on the java
layer yet. For instance to reset all recovery settings to their defaults a user can just specify `indices.recovery.*`.
This commit also adds strict settings validation, if a setting is unknown or if a setting can not be applied the entire
settings update request will fail.
Alexander Kazakov
Boaz Leskes
Jason Tedor
Ryan Ernst
David Pilato
Tanguy Leroux
Nik Everett
Simon Willnauer
javanna
Simon Willnauer
John Barker
Yannick Welsch
Adrien Grand
Yannick Welsch
Daniel Mitterdorfer
Robert Muir