I am not sure why we have this leniency for HTTP max content length, it
has been there since the beginning
(5ac51ee93f) with no explanation of its
source. That said, our philosophy today is different than the philosophy
of the past where Elasticsearch would be quite lenient in its handling
of settings and today we aim for predictability for both users and
us. This commit removes leniency in the parsing of
http.max_content_length.
This commit adds a new setting `cluster.persistent_tasks.allocation.enable`
that can be used to enable or disable the allocation of persistent tasks.
The setting accepts the values `all` (default) or `none`. When set to
none, the persistent tasks that are created (or that must be reassigned)
won't be assigned to a node but will reside in the cluster state with
a no "executor node" and a reason describing why it is not assigned:
```
"assignment" : {
"executor_node" : null,
"explanation" : "persistent task [foo/bar] cannot be assigned [no
persistent task assignments are allowed due to cluster settings]"
}
```
Update allocation awareness docs
Today, the docs imply that if multiple attributes are specified the the
whole combination of values is considered as a single entity when
performing allocation. In fact, each attribute is considered separately. This
change fixes this discrepancy.
It also replaces the use of the term "awareness zone" with "zone or domain", and
reformats some paragraphs to the right width.
Fixes#29105
Values for the network.host setting can often contain a colon which is a
character that is considered special by YAML (these arise in IPv6
addresses and some of the special tags like ":ipv4"). As such, these
values need to be quoted or a YAML parser will be unhappy with
them. This commit adds a note to the docs regarding this.
Cluster settings shouldn't leak into the next test.
I played with failing the test if it left over any settings but that
felt like it added more ceremony then it was worth. The advantage is
that any test that intentionally wants to leave settings in place after
the test would fail and require looking at but, so far as I can tell, we
don't have any such tests.
Clear the disk watermark after the snippet showing users how to set it.
Without this our tests will fail if the disks have less than 10GB free.
Closes#28325
Allowing `_doc` as a type will enable users to make the transition to 7.0
smoother since the index APIs will be `PUT index/_doc/id` and `POST index/_doc`.
This also moves most of the documentation to `_doc` as a type name.
Closes#27750Closes#27751
* Add accounting circuit breaker and track segment memory usage
This commit adds a new circuit breaker "accounting" that is used for tracking
the memory usage of non-request-tied memory users. It also adds tracking for the
amount of Lucene segment memory used by a shard as a user of the new circuit
breaker.
The Lucene segment memory is updated when the shard refreshes, and removed when
the shard relocates away from a node or is deleted. It should also be noted that
all tracking for segment memory uses `addWithoutBreaking` so as not to fail the
shard if a limit is reached.
The `accounting` breaker has a default limit of 100% and will contribute to the
parent breaker limit.
Resolves#27044
Today Cross Cluster Search requires at least one node in each remote cluster to be up once the cross cluster search is run. Otherwise the whole search request fails despite some of the data (either local and/or remote) is available. This happens when performing the _search/shards calls to find out which remote shards the query has to be executed on. This scenario is different from shard failures that may happen later on when the query is actually executed, in case e.g. remote shards are missing, which is not going to fail the whole request but rather yield partial results, and the _shards section in the response will indicate that.
This commit introduces a boolean setting per cluster called search.remote.$cluster_alias.skip_if_disconnected, set to false by default, which allows to skip certain clusters if they are down when trying to reach them through a cross cluster search requests. By default all clusters are mandatory.
Scroll requests support such setting too when they are first initiated (first search request with scroll parameter), but subsequent scroll rounds (_search/scroll endpoint) will fail if some of the remote clusters went down meanwhile.
The search API response contains now a new _clusters section, similar to the _shards section, that gets returned whenever one or more clusters were disconnected and got skipped:
"_clusters" : {
"total" : 3,
"successful" : 2,
"skipped" : 1
}
Such section won't be part of the response if no clusters have been skipped.
The per cluster skip_unavailable setting value has also been added to the output of the remote/info API.
Removing several occurrences of this typo in the docs and javadocs, seems to be
a common mistake. Corrections turn up once in a while in PRs, better to correct
some of this in one sweep.
The current script service has a script compilation limit for a one
minute window. This is set to a small default value of 15. Instead of
increasing that default value, this commit introduces a new setting
that allows to configure a rate per time unit, so that the script service can deal with bursts better.
The new setting is named `script.max_compilations_rate`,
requires a nonnegative number and a positive time value.
The default is `75/5m`, which is equivalent to the existing 15 per minute.
The names of two settings in the script security docs are incorrect,
referring to the prefix as "scripts" instead of "script". This commit
fixes this issue.
Relates #26236
This commit adds a small note to the discovery docs to include a note
that we recommend that the unicast hosts list be maintained as the list
of master-eligible nodes in the cluster.
Relates #25991
Requests that execute a stored script will no longer be allowed to specify the lang of the script. This information is stored in the cluster state making only an id necessary to execute against. Putting a stored script will still require a lang.
This commit adds cross-settings validation for the low/high/flood stage
disk watermark settings. This validation was enabled by the introduction
of multiple settings validation.
Relates #25600
Today when we run out of disk all kinds of crazy things can happen
and nodes are becoming hard to maintain once out of disk is hit.
While we try to move shards away if we hit watermarks this might not
be possible in many situations. Based on the discussion in #24299
this change monitors disk utilization and adds a flood-stage watermark
that causes all indices that are allocated on a node hitting the flood-stage
mark to be switched read-only (with the option to be deleted). This allows users to react on the low disk
situation while subsequent write requests will be rejected. Users can switch
individual indices read-write once the situation is sorted out. There is no
automatic read-write switch once the node has enough space. This requires
user interaction.
The flood-stage watermark is set to `95%` utilization by default.
Closes#24299
This commit adds a note to the docs regarding explicilty setting a
publish host if the network.host setting results in multiple bind
addresses.
Relates #25496
This commit removes path.conf as a valid setting and replaces it with a
command-line flag for specifying a non-default path for configuration.
Relates #25392
This commit adds back "id" as the key within a script to specify a
stored script (which with file scripts now gone is no longer ambiguous).
It also adds "source" as a replacement for "code". This is in an attempt
to normalize how scripts are specified across both put stored scripts and script usages, including search template requests. This also deprecates the old inline/stored keys.
This PR adds a new thread pool type: `fixed_auto_queue_size`. This thread pool
behaves like a regular `fixed` threadpool, except that every
`auto_queue_frame_size` operations (default: 10,000) in the thread pool,
[Little's Law](https://en.wikipedia.org/wiki/Little's_law) is calculated and
used to adjust the pool's `queue_size` either up or down by 50. A minimum and
maximum is taken into account also. When the min and max are the same value, a
regular fixed executor is used instead.
The `SEARCH` threadpool is changed to use this new type of thread pool. However,
the min and max are both set to 1000, meaning auto adjustment is opt-in rather
than opt-out.
Resolves#3890
In scripts (at least some of the languages), the terms dictionary and
postings can be access with the special _index variable. This is for
very advanced use cases which want to do their own scoring. The problem
is segment level statistics must be recomputed for every document.
Additionally, this is not friendly to the terms index caching as the
order of looking up terms should be controlled by lucene.
This change removes _index from scripts. Anyone using it can and should
instead write a Similarity plugin, which is explicitly designed to allow
doing the calculations needed for a relevance score.
closes#19359
Today when an index is `read-only` the index is also blocked from
being deleted which sometimes is undesired since in-order to make
changes to a cluster indices must be deleted to free up space. This is
a likely scenario in a hosted environment when disk-space is limited to switch
indices read-only but allow deletions to free up space.
This commit documents how to write a `ScriptEngine` in order to use
expert internal apis, such as using Lucene directly to find index term
statistics. These documents prepare the way to remove both native
scripts and IndexLookup.
The example java code is actually compiled and tested under a new gradle
subproject for example plugins. This change does not yet breakup
jvm-example into the new examples dir, which should be done separately.
relates #19359
relates #19966
Currently, the get snapshots API (e.g. /_snapshot/{repositoryName}/_all)
provides information about snapshots in the repository, including the
snapshot state, number of shards snapshotted, failures, etc. In order
to provide information about each snapshot in the repository, the call
must read the snapshot metadata blob (`snap-{snapshot_uuid}.dat`) for
every snapshot. In cloud-based repositories, this can be expensive,
both from a cost and performance perspective. Sometimes, all the user
wants is to retrieve all the names/uuids of each snapshot, and the
indices that went into each snapshot, without any of the other status
information about the snapshot. This minimal information can be
retrieved from the repository index blob (`index-N`) without needing to
read each snapshot metadata blob.
This commit enhances the get snapshots API with an optional `verbose`
parameter. If `verbose` is set to false on the request, then the get
snapshots API will only retrieve the minimal information about each
snapshot (the name, uuid, and indices in the snapshot), and only read
this information from the repository index blob, thereby giving users
the option to retrieve the snapshots in a repository in a more
cost-effective and efficient manner.
Closes#24288
Adds CONSOLE to cross-cluster-search docs but skips them for testing
because we don't have a second cluster set up. This gets us the
`VIEW IN CONSOLE` and `COPY AS CURL` links and makes sure that they
are valid yaml (not json, technically) but doesn't get testing.
Which is better than we had before.
Adds CONSOLE to the dynamic templates docs and ingest-node docs.
The ingest-node docs contain a *ton* of non-console snippets. We
might want to convert them to full examples later, but that can be
a separate thing.
Relates to #18160
This commit adds a link to the minimum master nodes section of the
important settings docs from the Zen discovery docs to clarify the
meaning and importance of setting minimum master nodes to a quorum of
master-eligible nodes.
Relates #24311
I just spent ages debugging a script I wrote after following the documentation. It was not clear to me that _index is not defined when using painless; if it was mentioned on this page I would have saved myself a lot of time.
Drops any mention of non-sandboxed scripting languages other than a
brief "we don't support them and we shouldn't because A and B"
statement.
Relates to #23930
They needed to be updated now that Painless is the default and
the non-sandboxed scripting languages are going away or gone.
I dropped the entire section about customizing the classloader
whitelists. In master this barely does anything (exposes more
things to expressions).
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
This commit brings the snapshot documentation in conformity
with the CONSOLE format, and fixes the docs so that the documentation
tests can be run against them.
Painless uses Ruby-like method dispatch (reciever type, method name,
and arity) rather than Java-like (reciever type, method name, and
argument compile time types) or Groovy-like method dispatch (receiver
type, method name, and argument run time types). We do this for
mostly good reasons but we never documented it.
Relates to #22720
Today either all nodes in the cluster connect to remote clusters of only nodes
that have remote clusters configured in their node config. To allow global remote
cluster configuration but restrict connections to a set of nodes in the cluster
this change adds a new setting `search.remote.connect` (defaults to `true`) to allow
to disable remote cluster connections on a per node basis.
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
Implemented by wrapping an array of reused `ModuleDateTime`s that
we grow when needed. The `ModuleDateTime`s are reused when we
move to the next document.
Also improves the error message returned when attempting to modify
the `ScriptdocValues`, removes a couple of allocations, and documents
that the date functions are available in Painless.
Relates to #22162
Currently, stored scripts use a namespace of (lang, id) to be put, get, deleted, and executed. This is not necessary since the lang is stored with the stored script. A user should only have to specify an id to use a stored script. This change makes that possible while keeping backwards compatibility with the previous namespace of (lang, id). Anywhere the previous namespace is used will log deprecation warnings.
The new behavior is the following:
When a user specifies a stored script, that script will be stored under both the new namespace and old namespace.
Take for example script 'A' with lang 'L0' and data 'D0'. If we add script 'A' to the empty set, the scripts map will be ["A" -- D0, "A#L0" -- D0]. If a script 'A' with lang 'L1' and data 'D1' is then added, the scripts map will be ["A" -- D1, "A#L1" -- D1, "A#L0" -- D0].
When a user deletes a stored script, that script will be deleted from both the new namespace (if it exists) and the old namespace.
Take for example a scripts map with {"A" -- D1, "A#L1" -- D1, "A#L0" -- D0}. If a script is removed specified by an id 'A' and lang null then the scripts map will be {"A#L0" -- D0}. To remove the final script, the deprecated namespace must be used, so an id 'A' and lang 'L0' would need to be specified.
When a user gets/executes a stored script, if the new namespace is used then the script will be retrieved/executed using only 'id', and if the old namespace is used then the script will be retrieved/executed using 'id' and 'lang'
Adds "Appending B. Painless API Reference", a reference of all classes
and methods available from Painless. Removes links to java packages
because they contain methods that we don't expose and don't contain
methods that we do expose (the ones in Augmentation). Instead this
generates a list of every class and every exposed method using the same
type information available to the
interpreter/compiler/whatever-we-call-it. From there you can jump to
the relevant docs.
Right now you build all the asciidoc files by running
```
gradle generatePainlessApi
```
These files are expected to be committed because we build the docs
without running `gradle`.
Also changes the output of `Debug.explain` so that it is easy to
search for the class in the generated reference documentation.
You can also run it in an IDE safely if you pass the path to the
directory in which to generate the docs as the first parameter. It'll
blow away the entire directory an recreate it from scratch so be careful.
And then you can build the docs by running something like:
```
../docs/build_docs.pl --out ../built_docs/ --doc docs/reference/index.asciidoc --open
```
That is, if you have checked out https://github.com/elastic/docs in
`../docs`. Wait a minute or two and your browser will pop open in with
all of Elasticsearch's reference documentation. If you go to
`http://localhost:8000/painless-api-reference.html` you can see this
list. Or you can get there by following the links to `Modules` and
`Scripting` and `Painless` and then clicking the link in the paragraphs
below titled `Appendix B. Painless API Reference`.
I like having these in asciidoc because we can deep link to them from the
rest of the guide with constructs like
`<<painless-api-reference-Object-hashCode-0>>` and
`<<painless-api-reference->>` and we get link checking. Then the only
brittle link maintenance bit is the link generation for javadoc. Which
sucks. But I think it is important that we link to the methods directly
so they are easy to find.
Relates to #22720
Jason Tedor
Yannick Welsch
Tanguy Leroux
Ryan Ernst
David Turner
Ali El broudi
Simon Willnauer
Nik Everett
Peter Dyson
Adrien Grand
Glen Smith
Lee Hinman
Christoph Büscher
Luca Cavanna
Ulrich Reffle
Shubham Aggarwal
Igor Motov
javanna
Clinton Gormley
Anton Pozhidaev
Deb Adair
Shane Connelly
lcawley
Christoph Büscher
marcocova
Alexander Reelsen
Aron Szanto
Jack Conradson
Herman Schaaf
Robin Clarke
Jack Conradson
Lee Hinman
Chris Ivens
Ali Beyad
Till Backhaus
farisk
Iliiaz Akhmedov
wyukawa
Stefan Gorgiovski
Jay Modi
Boaz Leskes
Tim Brooks
alamzeeshan