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.
This commit removes some references to 5.x that were picked up when the
migration docs for the cat API were migrated from 5.x to master.
Relates #21342
This commit adds migration docs for the cat API, including a note
regarding the change in response in the cat thread pool API for
unbounded queue sizes.
Relates #21342
We plan to deprecate `_suggest` during 5.0 so it isn't worth fixing
it to support the `_source` parameter for `_source` filtering. But we
should fix the docs so they are accurate.
Since this removes the last non-`// CONSOLE` line in
`completion-suggest.asciidoc` this also removes it from the list of
files that have non-`// CONSOLE` docs.
Closes#20482
Adds support for `?slices=N` to reindex which automatically
parallelizes the process using parallel scrolls on `_uid`. Performance
testing sees a 3x performance improvement for simple docs
on decent hardware, maybe 30% performance improvement
for more complex docs. Still compelling, especially because
clusters should be able to get closer to the 3x than the 30%
number.
Closes#20624
Exist requests are supposed to never throw an exception, but rather return true or false depending on whether some resource exists or not. Indices exists does that for indices and accepts wildcard expressions too. The way the api works internally is by resolving indices and catching IndexNotFoundException: if an exception is thrown the index does not exist hence it returns false, otherwise it returns true. That works ok only if ignore_unavailable and allow_no_indices indices options are both set to false, meaning that they are strict and any missing index or wildcard expressions that resolves to no indices will lead to an exception that can be thrown and cause false to be returned.
Unfortunately the indices options have been configurable up until now for this request, meaning that one can set ignore_unavailable or allow_no_indices to true and have the indices exist request return true for indices that really don't exist, which makes very little sense in the context of this api.
This commit removes the indicesOptions setter from the IndicesExistsRequest and makes settable only expandWildcardsOpen and expandWildcardsClosed, hence a subset of the available indices options. This way we can guarantee more consistent behaviour of the indices exists api. We can then remove the ignore_unavailable and allow_no_indices option from indices exists api spec
Moves the `_flush` in the `_cat/indices` snippets testing framework
to the very first test. We need to flush super early because index
size is cached for a few seconds so we really need to read a
consistent size on the first read so we can sort by it properly.
Closes#21062
This commit introduces a new execution mode for the query_string query, which
is intended down the road to be a replacement for the current _all field.
It now does auto-field-expansion and auto-leniency when the following criteria
are ALL met:
The _all field is disabled
No default_field has been set in the index settings
No default_field has been set in the request
No fields are specified in the request
Additionally, a user can force the "all-like" execution by setting the
all_fields parameter to true.
When executing in all field mode, the query_string query will look at all the
fields in the mapping that are not metafields and can be searched, and
automatically expand the list of fields that are going to be queried.
Relates to #19784
The important settings docs previously referred to a section regarding
the node.max_local_storage_nodes setting. This section was removed, but
the link was not. This commit removes that link.
Previously node.max_local_storage_nodes defaulted to fifty, and this
permitted users to start multiple instances of Elasticsearch sharing the
same data folder. This can be dangerous, and usually it does not make
sense to run more than one instance of Elasticsearch on a single
server. Because of this, we had a note in the important settings docs
advising users to set this setting to one. However, we have since
changed the default value of this setting to one so this advise is no
longer needed.
Relates #21305
This query is deprecated from 5.0 on. Similar to IndicesQueryBuilder we should
log a deprecation warning whenever this query is used.
Relates to #15760
Lucene 6.2 introduces the new `Analyzer.normalize` API, which allows to apply
only character-level normalization such as lowercasing or accent folding, which
is exactly what is needed to process queries that operate on partial terms such
as `prefix`, `wildcard` or `fuzzy` queries. As a consequence, the
`lowercase_expanded_terms` option is not necessary anymore. Furthermore, the
`locale` option was only needed in order to know how to perform the lowercasing,
so this one can be removed as well.
Closes#9978
This change adds an option called `split_on_whitespace` which prevents the query parser to split free text part on whitespace prior to analysis. Instead the queryparser would parse around only real 'operators'. Default to true.
For instance the query `"foo bar"` would let the analyzer of the targeted field decide how the tokens should be splitted.
Some options are missing in this change but I'd like to add them in a follow up PR in order to be able to simplify the backport in 5.x. The missing options (changes) are:
* A `type` option which similarly to the `multi_match` query defines how the free text should be parsed when multi fields are defined.
* Simple range query with additional tokens like ">100 50" are broken when `split_on_whitespace` is set to false. It should be possible to preserve this syntax and make the parser aware of this special syntax even when `split_on_whitespace` is set to false.
* Since all this options would make the `query_string_query` very similar to a match (multi_match) query we should be able to share the code that produce the final Lucene query.
* Add docs with up to date instructions on updating default similarity
The default similarity can no longer be set in the configuration file
(you will get an error on startup). Update the docs with the method
that works.
* Add instructions for changing similarity on index creation
It was 10mb and that was causing trouble when folks reindex-from-remoted
with large documents.
We also improve the error reporting so it tells folks to use a smaller
batch size if they hit a buffer size exception. Finally, adds some docs
to reindex-from-remote mentioning the buffer and giving an example of
lowering the size.
Closes#21185
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
Lucene 6.3 is expected to be released in the next weeks so it'd be good to give
it some integration testing. I had to upgrade randomized-testing too so that
both Lucene and Elasticsearch are on the same version.
Nik Everett
Jason Tedor
Clinton Gormley
javanna
Ryan Ernst
Joeyn414
Adrien Grand
markharwood
Loek van Gool
Luca Cavanna
Lee Hinman
Chris Earle
Christoph Büscher
Jim Ferenczi
Alexander Lin
Adriel Dean-Hall
Craig Squire
LakumiNarayanan
Jack Conradson
Lee Hinman
Stanislav Mamontov