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
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.
Rename `fields` to `stored_fields` and add `docvalue_fields`
`stored_fields` parameter will no longer try to retrieve fields from the _source but will only return stored fields.
`fields` will throw an exception if the user uses it.
Add `docvalue_fields` as an adjunct to `fielddata_fields` which is deprecated. `docvalue_fields` will try to load the value from the docvalue and fallback to fielddata cache if docvalues are not enabled on that field.
Closes#18943
These are useful methods in groovy that give you control over
the replacements used:
```
'the quick brown fox'.replaceAll(/[aeiou]/,
m -> m.group().toUpperCase(Locale.ROOT))
```
`stored_fields` parameter will no longer try to retrieve fields from the _source but will only return stored fields.
`fields` will throw an exception if the user uses it.
Add `docvalue_fields` as an adjunct to `fielddata_fields` which is deprecated. `docvalue_fields` will try to load the value from the docvalue and fallback to fielddata cache if docvalues are not enabled on that field.
Closes#18943
ES only sends a non-200 response all shards fail but we should
fail the tests generated by docs if any of them fail.
Depending on the outcome of #18978 this might be a temporary
workaround.
Painless: Add support for //m
Painless: Add support for //s
Painless: Add support for //i
Painless: Add support for //u
Painless: Add support for //U
Painless: Add support for //l
This means "literal" and is exposed for completeness sake with
the java api.
Painless: Add support for //c
c enables Java's CANON_EQ (canonical equivalence) flag which makes
unicode characters that are canonically equal match. Java's javadoc
gives "a\u030A" being equal to "\u00E5". That is that the "a" code
point followed by the "combining ring above" code point is equal to
the "a with combining ring above" code point.
Update docs and add multi-flag test
Whitelist most of the Pattern class.
Adds support for the find operator (=~) and the match operator (==~)
to painless's regexes. Also whitelists most of the Matcher class and
documents regex support in painless.
The find operator (=~) returns a boolean that is the result of building
a matcher on the lhs with the Pattern on the RHS and calling `find` on
it. Use it like this:
```
if (ctx._source.last =~ /b/)
```
The match operator (==~) returns boolean like find but instead of calling
`find` on the Matcher it calls `matches`.
```
if (ctx._source.last ==~ /[^aeiou].*[aeiou]/)
```
Finally, if you want the actual matcher you do:
```
Matcher m = /[aeiou]/.matcher(ctx._source.last)
```
The syntax highlighter only supports [source,js].
Also adds a check to the rest test generator that runs during
the build that'll fail the build if it sees `[source,json]`.
This removes all the mentions of the sandbox from the script engine
services and permissions model. This means that the following settings
are no longer supported:
```yaml
script.inline: sandbox
script.stored: sandbox
```
Instead, only a `true` or `false` value can be specified.
Since this would otherwise break the default-allow parameter for
languages like expressions, painless, and mustache, all script engines
have been updated to have individual settings, for instance:
```yaml
script.engine.groovy.inline: true
```
Would enable all inline scripts for groovy. (they can still be
overridden on a per-operation basis).
Expressions, Painless, and Mustache all default to `true` for inline,
file, and stored scripts to preserve the old scripting behavior.
Resolves#17114
Remove performance hack for accessing a document's fields, its not needed.
Add support for accessing is-getter methods like List.isEmpty() as .empty
Closes#18201
This gives better coverage and consistency with the scripting APIs, by
whitelisting the primary search scripting API classes and using them instead
of only Map and List methods.
For example, accessing fields can now be done with `.value` instead of `.0`
because `getValue()` is whitelisted. For now, access to a document's fields in
this way (loads) are fast-pathed in the code, to avoid dynamic overhead.
Access to geo fields and geo distance functions is now supported.
TODO: date support (e.g. whitelist ReadableDateTime methods as a start)
TODO: improve docs (like expressions and groovy have for document's fields)
TODO: remove fast-path hack
Closes#18169
Squashed commit of the following:
commit ec9f24b2424891a7429bb4c0a03f9868cba0a213
Author: Robert Muir <rmuir@apache.org>
Date: Thu May 5 17:59:37 2016 -0400
cutover to <Def> instead of <Object> here
commit 9edb1550438acd209733bc36f0d2e0aecf190ecb
Author: Robert Muir <rmuir@apache.org>
Date: Thu May 5 17:03:02 2016 -0400
add fast-path for docvalues field loads
commit f8e38c0932fccc0cfa217516130ad61522e59fe5
Author: Robert Muir <rmuir@apache.org>
Date: Thu May 5 16:47:31 2016 -0400
Painless: add fielddata accessors (.value/.values/.distance()/etc)
Adds infrastructure so `gradle :docs:check` will extract tests from
snippets in the documentation and execute the tests. This is included
in `gradle check` so it should happen on CI and during a normal build.
By default each `// AUTOSENSE` snippet creates a unique REST test. These
tests are executed in a random order and the cluster is wiped between
each one. If multiple snippets chain together into a test you can annotate
all snippets after the first with `// TEST[continued]` to have the
generated tests for both snippets joined.
Snippets marked as `// TESTRESPONSE` are checked against the response
of the last action.
See docs/README.asciidoc for lots more.
Closes#12583. That issue is about catching bugs in the docs during build.
This catches *some* bugs in the docs during build which is a good start.
* Reorganize scripting documentation
* Further changes to tidy up scripting docs
Closes#18116
* Add note about .lat/lon potentially returning null
* Added .value to expressions example
* Fixed two bad ASCIIDOC links