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
Today when you do not specify a port for an entry in
discovery.zen.ping.unicast.hosts, the default port is the value of the
setting transport.profiles.default.port and falls back to the value of
transport.tcp.port if this is not set. For a node that is explicitly
bound to a different port than the default port, this means that the
default port will be equal to this explicitly bound port. Yet, the docs
say that we fall back to 9300 here. This commit corrects the docs.
Relates #22568
Instead of `search.remote.seeds.${clustername}` we now specify the seeds as:
`search.remote.${clustername}.seeds` which is a real list setting compared to an unvalidated
group setting before.
The `Script source settings` section currently states that `false` means scripting is ENABLED.
The other sections seem to indicate that `false` means scripting is DISABLED.
If the current documentation is correct, that would imply that `inline` and `stored` scripting are ENABLED by default, which seems to conflict with all the other sections in the document.
Sends the `error_trace` parameter with all requests sent by the
yaml test framework, including the doc snippet tests. This can be
overridden by settings `error_trace: false`. While this drift's
core's handling of the yaml tests from the client's slightly this
should only be a problem for tests that rely on the default value,
both of which I've fixed by setting the value explicitly.
This also escapes `\n` and `\t` in the `Stash dump on failure` so
the `stack_trace` is more readable.
Also fixes `RestUpdateSettingsAction` to not think of the `error_trace`
parameter as a setting.
Elasticsearch can be run in a few different ways:
- from the command line on Linux and Windows
- as a service on Linux and Windows
on both 32-bit client and 64-bit server VMs. We strive for a great
out-of-the-box experience any of these combinations but today it is
lacking on 32-bit client JVMs and on the Windows service. There are two
deficiencies that arise:
- on any 32-bit client JVM we fail to start out of the box because we
force the server JVM in jvm.options
- when installing the Windows service, the thread stack size must be
specified in jvm.options
This commit attempts to address these deficiencies.
We should continue to force the server JVM because there are systems
where the server JVM is not active by default (e.g., the 32-bit JDK on
Windows). This does mean that if a user tries to run with a client JVM
they will see a failure message at startup but this is the best that we
can do if we want to continue to force the server JVM. Thus, this commit
at least documents this situation.
To improve the situation with installing the Windows service, this
commit adds a default setting for the thread stack size. This default is
chosen based on the default thread stack size across all 64-bit server
JVMs. This means that if a user tries to run with a 32-bit JVM they
could otherwise see significantly higher memory usage (this situation is
complicated, it's really only on Windows where the extra memory usage is
egregious, but cutting into the 32-bit address space on any system is
bad). So this commit makes it so that the out-of-the-box experience is
improved for the Windows service on 64-bit server JVMs and we document
the need to adjust this setting on 32-bit JVMs.
Again, we are focusing on the out-of-the-box experience here and this
means optimizing for the best experience on any 64-bit server JVM as
this covers the vast majority of the user base. The users that are on
32-bit JVMs will suffer a little bit but at least now any user on any
64-bit server JVM can start Elasticsearch out of the box.
Finally, we fix some references to the jvm.options documentation.
Relates #21920
NOTE: The result of `?.` and `?:` can't be assigned to primitives. So
`int[] someArray = null; int l = someArray?.length` and
`int s = params.size ?: 100` don't work. Do
`def someArray = null; def l = someArray?.length` and
`def s = params.size ?: 100` instead.
Relates to #21748
* Scripting: Remove groovy scripting language
Groovy was deprecated in 5.0. This change removes it, along with the
legacy default language infrastructure in scripting.
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
You can use `Debug.explain(someObject)` in painless to throw an
`Error` that can't be caught by painless code and contains an
object's class. This is useful because painless's sandbox doesn't
allow you to call `someObject.getClass()`.
Closes#20263
Implements a null coalescing operator in painless that looks like `?:`. This form was chosen to emulate Groovy's `?:` operator. It is different in that it only coalesces null values, instead of Groovy's `?:` operator which coalesces all falsy values. I believe that makes it the same as Kotlin's `?:` operator. In other languages this operator looks like `??` (C#) and `COALESCE` (SQL) and `:-` (bash).
This operator is lazy, meaning the right hand side is only evaluated at all if the left hand side is null.
This change was reverted after it caused random test failures. This was
due to a copy/paste error in the original PR which caused the mock
version of ClusterInfoService to be used whenever the mock *ZenPing* was
used, and the real ClusterInfoService to be used when MockZenPing was
not used.
Null safe dereferences make handling null or missing values shorter.
Compare without:
```
if (ctx._source.missing != null && ctx._source.missing.foo != null) {
ctx._source.foo_length = ctx.source.missing.foo.length()
}
```
To with:
```
Integer length = ctx._source.missing?.foo?.length();
if (length != null) {
ctx._source.foo_length = length
}
```
Combining this with the as of yet unimplemented elvis operator allows
for very concise defaults for nulls:
```
ctx._source.foo_length = ctx._source.missing?.foo?.length() ?: 0;
```
Since you have to start somewhere, we started with null safe dereferenes.
Anyway, this is a feature borrowed from groovy. Groovy allows writing to
null values like:
```
def v = null
v?.field = 'cat'
```
And the writes are simply ignored. Painless doesn't support this at this
point because it'd be complex to implement and maybe not all that useful.
There is no runtime cost for this feature if it is not used. When it is
used we implement it fairly efficiently, adding a jump rather than a
temporary variable.
This should also work fairly well with doc values.
Refactored ScriptType to clean up some of the variable and method names. Added more documentation. Deprecated the 'in' ParseField in favor of 'stored' to match the indexed scripts being replaced by stored scripts.
Adds support for indexing into lists and arrays with negative
indexes meaning "counting from the back". So for if
`x = ["cat", "dog", "chicken"]` then `x[-1] == "chicken"`.
This adds an extra branch to every array and list access but
some performance testing makes it look like the branch predictor
successfully predicts the branch every time so there isn't a
in execution time for this feature when the index is positive.
When the index is negative performance testing showed the runtime
is the same as writing `x[x.length - 1]`, again, presumably thanks
to the branch predictor.
Those performance metrics were calculated for lists and arrays but
`def`s get roughly the same treatment though instead of inlining
the test they need to make a invoke dynamic so we don't screw up
maps.
Closes#20870
It is important that folks understand that snapshot/restore isn't
for archiving. It is appropriate for backup and disaster recovery
but not for archival over long periods of time because of version
incompatibility.
Closes#20866
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.
* plugins/discovery-azure-class.asciidoc
* reference/cluster.asciidoc
* reference/modules/cluster/misc.asciidoc
* reference/modules/indices/request_cache.asciidoc
After this is merged there will be no unconvereted snippets outside
of `reference`.
Related to #18160
`cluster.routing.allocation.cluster_concurrent_rebalance` setting,
clarifying in which shard allocation situations the rebalance limit
takes effect.
Closes#20529
In 7560101ec7, the Elasticsearch logger
names were modified to be their fully-qualified class name (with some
exceptions for special loggers like the slow logs and the transport
tracer). This commit updates the docs accordingly.
Relates #20475
>However, the version of the new cluster should be the same or newer than the cluster that was
Afaik, you can't restore a snapshot to a newer cluster that is not consecutively newer (i.e. can't restore 1.x snapshot to a 5.x cluster). This is to clarify the statement above moving forward.
When compiling many dynamically changing scripts, parameterized
scripts (<https://www.elastic.co/guide/en/elasticsearch/reference/master/modules-scripting-using.html#prefer-params>)
should be preferred. This enforces a limit to the number of scripts that
can be compiled within a minute. A new dynamic setting is added -
`script.max_compilations_per_minute`, which defaults to 15.
If more dynamic scripts are sent, a user will get the following
exception:
```json
{
"error" : {
"root_cause" : [
{
"type" : "circuit_breaking_exception",
"reason" : "[script] Too many dynamic script compilations within one minute, max: [15/min]; please use on-disk, indexed, or scripts with parameters instead",
"bytes_wanted" : 0,
"bytes_limit" : 0
}
],
"type" : "search_phase_execution_exception",
"reason" : "all shards failed",
"phase" : "query",
"grouped" : true,
"failed_shards" : [
{
"shard" : 0,
"index" : "i",
"node" : "a5V1eXcZRYiIk8lecjZ4Jw",
"reason" : {
"type" : "general_script_exception",
"reason" : "Failed to compile inline script [\"aaaaaaaaaaaaaaaa\"] using lang [painless]",
"caused_by" : {
"type" : "circuit_breaking_exception",
"reason" : "[script] Too many dynamic script compilations within one minute, max: [15/min]; please use on-disk, indexed, or scripts with parameters instead",
"bytes_wanted" : 0,
"bytes_limit" : 0
}
}
}
],
"caused_by" : {
"type" : "general_script_exception",
"reason" : "Failed to compile inline script [\"aaaaaaaaaaaaaaaa\"] using lang [painless]",
"caused_by" : {
"type" : "circuit_breaking_exception",
"reason" : "[script] Too many dynamic script compilations within one minute, max: [15/min]; please use on-disk, indexed, or scripts with parameters instead",
"bytes_wanted" : 0,
"bytes_limit" : 0
}
}
},
"status" : 500
}
```
This also fixes a bug in `ScriptService` where requests being executed
concurrently on a single node could cause a script to be compiled
multiple times (many in the case of a powerful node with many shards)
due to no synchronization between checking the cache and compiling the
script. There is now synchronization so that a script being compiled
will only be compiled once regardless of the number of concurrent
searches on a node.
Relates to #19396
GeoDistance is implemented using a crazy enum that causes issues with the scripting modules. This commit moves all distance calculations to arcDistance and planeDistance static methods in GeoUtils. It also removes unnecessary distance helper methods from ScriptDocValues.GeoPoints.
* Update gateway.asciidoc
Added a note to clarify that, in cases where nodes in a cluster have different setting, the node that is the elected master takes precedence over anything else.
* Update gateway.asciidoc
Updated as per @bleskes's comments
Jack Conradson
Ryan Ernst
Chris Ivens
Ali Beyad
Clinton Gormley
Nik Everett
Till Backhaus
farisk
Iliiaz Akhmedov
wyukawa
Shane Connelly
Igor Motov
Stefan Gorgiovski
Jay Modi
Boaz Leskes
Tim Brooks
Simon Willnauer
javanna
alamzeeshan
Jason Tedor
Martijn van Groningen
Dave Richardson
Paweł Bobruk
Lucas Bremgartner
lslxdx
Praveen Shukla
Joshua Rich
Pascal Borreli
Simon Willnauer
Dominik Stadler
Colin Goodheart-Smithe
Pius
Lee Hinman
Nicholas Knize
Brandon Wulf
markwalkom