* Integrate UnifiedHighlighter
This change integrates the Lucene highlighter called "unified" in the list of supported highlighters for ES.
This highlighter can extract offsets from either postings, term vectors, or via re-analyzing text.
The best strategy is picked automatically at query time and depends on the field and the query to highlight.
* Add top hits collapsing to search request
The field collapsing is done with a custom top docs collector that "collapse" search hits with same field value.
The distributed aspect is resolve using the two passes that the regular search uses. The first pass "collapse" the top hits, then the coordinating node merge/collapse the top hits from each shard.
```
GET _search
{
"collapse": {
"field": "category",
}
}
```
This change also adds an ExpandCollapseSearchResponseListener that intercepts the search response and expands collapsed hits using the CollapseBuilder#innerHit} options.
The retrieval of each inner_hits is done by sending a query to all shards filtered by the collapse key.
```
GET _search
{
"collapse": {
"field": "category",
"inner_hits": {
"size": 2
}
}
}
```
This change allows specifying alias/wildcard expression in indices_boost.
And added another format for specifying indices_boost. It accepts array of index name and boost pair.
If an index is included in multiple aliases/wildcard expressions, the first match will be used.
With new format, old format is marked as deprecated.
Closes#4756
The shards preference on a search request enables specifying a list of
shards to hit, and then a secondary preference (e.g., "_primary") can be
added. Today, the separator between the shards list and the secondary
preference is ';'. Unfortunately, this is also a valid separtor for URL
query parameters. This means that a preference like "_shards:0;_primary"
will be parsed into two URL parameters: "_shards:0" and "_primary". With
the recent change to strict URL parsing, the second parameter will be
rejected, "_primary" is not a valid URL parameter on a search
request. This means that this feature has never worked (unless the ';'
is escaped, but no one does that because our docs do not that, and there
was no indication from Elasticsearch that this did not work). This
commit changes the separator to '|'.
Relates #20786
Previously, this doc was using a field called "content". This is
confusing, especially when the doc starts talking about the content of
the content field. This change makes the field name "comment" which
is less ambiguous and also changes some related field names in the doc
to make a consistent example theme of editing docs around blog posts.
This causes the snippets to be tested during the build and gives
helpful links to the reader to open the docs in console or copy them
as curl commands.
Relates to #18160
Surprise! You can use sliced scroll to easily parallelize reindex
and friend. They support it because they use the same infrastructure
as a regular search to parse the search request. While we would like
to make an "automatic" option for parallelizing reindex, this manual
option works right now and is pretty convenient!
`profile.asciidoc` now runs all of its command but it doesn't validate
all of the results. Writing the validation is time consuming so I only
did some of it.
* Update rescoring docs in respect to sort
If sort is present in a query the rescore query is not executed. As long as this feature is neither implemented (see discussion in #6788) nor the combination of sort and rescoring raises an error, we should warn the user in the documentation about this.
* Missed a dot
This change replaces the fields parameter with stored_fields when it makes sense.
This is dictated by the renaming we made in #18943 for the search API.
The following list of endpoint has been changed to use `stored_fields` instead of `fields`:
* get
* mget
* explain
The documentation and the rest API spec has been updated to cope with the changes for the following APIs:
* delete_by_query
* get
* mget
* explain
The `fields` parameter has been deprecated for the following APIs (it is replaced by _source filtering):
* update: the fields are extracted from the _source directly.
* bulk: the fields parameter is used but fields are extracted from the source directly so it is allowed to have non-stored fields.
Some APIs still have the `fields` parameter for various reasons:
* cat.fielddata: the fields paramaters relates to the fielddata fields that should be printed.
* indices.clear_cache: used to indicate which fielddata fields should be cleared.
* indices.get_field_mapping: used to filter fields in the mapping.
* indices.stats: get stats on fields (stored or not stored).
* termvectors: fields are retrieved from the stored fields if possible and extracted from the _source otherwise.
* mtermvectors:
* nodes.stats: the fields parameter is used to concatenate completion_fields and fielddata_fields so it's not related to stored_fields at all.
Fixes#20155
This change adds a special field named _none_ that allows to disable the retrieval of the stored fields in a search request or in a TopHitsAggregation.
To completely disable stored fields retrieval (including disabling metadata fields retrieval such as _id or _type) use _none_ like this:
````
POST _search
{
"stored_fields": "_none_"
}
````
Adds `warnings` syntax to the yaml test that allows you to expect
a `Warning` header that looks like:
```
- do:
warnings:
- '[index] is deprecated'
- quotes are not required because yaml
- but this argument is always a list, never a single string
- no matter how many warnings you expect
get:
index: test
type: test
id: 1
```
These are accessible from the docs with:
```
// TEST[warning:some warning]
```
This should help to force you to update the docs if you deprecate
something. You *must* add the warnings marker to the docs or the build
will fail. While you are there you *should* update the docs to add
deprecation warnings visible in the rendered results.
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
`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
This commit removes the search preference _only_node as the same
functionality can be obtained by using the search preference
_only_nodes. This commit also adds a test that ensures that _only_nodes
will continue to support specifying node IDs.
Relates #18875
The search preference _prefer_node allows specifying a single node to
prefer when routing a request. This functionality can be enhanced by
permitting multiple nodes to be preferred. This commit replaces the
search preference _prefer_node with the search preference _prefer_nodes
which supplants the former by specifying a single node and otherwise
adds functionality.
Relates #18872
API:
```
curl -XGET 'localhost:9200/twitter/tweet/_search?scroll=1m' -d '{
"slice": {
"field": "_uid", <1>
"id": 0, <2>
"max": 10 <3>
},
"query": {
"match" : {
"title" : "elasticsearch"
}
}
}
```
<1> (optional) The field name used to do the slicing (_uid by default)
<2> The id of the slice
By default the splitting is done on the shards first and then locally on each shard using the _uid field
with the following formula:
`slice(doc) = floorMod(hashCode(doc._uid), max)`
For instance if the number of shards is equal to 2 and the user requested 4 slices then the slices 0 and 2 are assigned
to the first shard and the slices 1 and 3 are assigned to the second shard.
Each scroll is independent and can be processed in parallel like any scroll request.
Closes#13494
We should prevent highlighting if a field is anything but a text or keyword field.
However, someone might implement a custom field type that has text and still want to
highlight on that. We cannot know in advance if the highlighter will be able to
highlight such a field and so we do the following:
If the field is only highlighted because the field matches a wildcard we assume
it was a mistake and do not process it.
If the field was explicitly given we assume that whoever issued the query knew
what they were doing and try to highlight anyway.
closes#17537
Fix a limitation that prevent from hierarchical inner hits be defined in query dsl.
Removed the nested_path, parent_child_type and query options from inner hits dsl. These options are only set by ES
upon parsing the has_child, has_parent and nested queries are using their respective query builders.
These options are still used internally, when these options are set a new private copy is created based on the
provided InnerHitBuilder and configuring either nested_path or parent_child_type and the inner query of the query builder
being used.
Closes#11118
IMHO the original text here was incomplete. Adding the simple words 'in the index mapping' makes this sentence more clear. Perhaps a be more clear to make this a link.
Both top level and inline inner hits are now covered by InnerHitBuilder.
Although there are differences between top level and inline inner hits,
they now make use of the same builder logic.
The parsing of top level inner hits slightly changed to be more readable.
Before the nested path or parent/child type had to be specified as encapsuting
json object, now these settings are simple fields. Before this was required
to allow streaming parsing of inner hits without missing contextual information.
Once some issues are fixed with inline inner hits (around multi level hierachy of inner hits),
top level inner hits will be deprecated and removed in the next major version.
The search_after parameter provides a way to efficiently paginate from one page to the next. This parameter accepts an array of sort values, those values are then used by the searcher to sort the top hits from the first document that is greater to the sort values.
This parameter must be used in conjunction with the sort parameter, it must contain exactly the same number of values than the number of fields to sort on.
NOTE: A field with one unique value per document should be used as the last element of the sort specification. Otherwise the sort order for documents that have the same sort values would be undefined. The recommended way is to use the field `_uuid` which is certain to contain one unique value for each document.
Fixes#8192
The only way to refer to the plain highlighter is now `plain`, the only way to refer to the fast vector highlighter is `fvh` and the only way to refer to the postings highlighter is `postings`. The name variants like `highlighter`, `postings-highlighter` and `fast-vector-highlighter` have been removed.
Requesting a million hits, or page 100,000 is always a bad idea, but users
may not be aware of this. This adds a per-index limit on the maximum size +
from that can be requested which defaults to 10,000.
This should not interfere with deep-scrolling.
Closes#9311
The documentation states that scrolls are automatically closed when all
documents are consumed, but this is not the case. I first tried to fix
the code to close scrolls automatically but this made REST tests fail
because clearing a scroll that is already closed returned a 4xx error
instead of a 2xx code, so this has probably been this way for a very long
time.
Just like specifying `?preference=_primary`, this adds the ability to
specify `?preference=_replica` or `?preference=_replica_first` on
requests that support it.
Resolves#12222
This change unifies the way scripts and templates are specified for all instances in the codebase. It builds on the Script class added previously and adds request building and parsing support as well as the ability to transfer script objects between nodes. It also adds a Template class which aims to provide the same functionality for template APIs
Closes#11091
The default `false` for `require_field_match` is a bit odd and confusing for users, given that field names get ignored by default and every field gets highlighted if it contains terms extracted out of the query, regardless of which fields were queries. Changed the default to `true`, it can always be changed per request.
Closes#10627Closes#11067
Our own fork of the lucene PostingsHighlighter is not easy to maintain and doesn't give us any added value at this point. In particular, it was introduced to support the require_field_match option and discrete per value highlighting, used in case one wants to highlight the whole content of a field, but get back one snippet per value. These two features won't
make it into lucene as they slow things down and shouldn't have been supported from day one on our end probably.
One other customization we had was support for a wider range of queries via custom rewrite etc. (yet another way to slow
things down), which got added to lucene and works much much better than what we used to do (instead of or rewrite, term
s are pulled out of the automata for multi term queries).
Removing our fork means the following in terms of features:
- dropped support for require_field_match: the postings highlighter will only highlight fields that were queried
- some custom es queries won't be supported anymore, meaning they won't be highlighted. The only one I found up until now is the phrase_prefix. Postings highlighter rewrites against an empty reader to avoid slow operations (like the ones that we were performing with the fork that we are removing here), thus the prefix will not be expanded to any term. What the postings highlighter does instead is pulling the automata out of multi term queries, but this is not supported at the moment with our MultiPhrasePrefixQuery.
Closes#10625Closes#11077
Add methods to operate on multi-valued fields in the expressions language.
Note that users will still not be able to access individual values
within a multi-valued field.
The following methods will be included:
* min
* max
* avg
* median
* count
* sum
Additionally, changes have been made to MultiValueMode to support the
new median method.
closes#11105
Remove the ability to specify search type ‘query_and_fetch’ and
‘df_query_and_fetch’ from the REST API.
- Adds REST tests
- Updates REST API spec to remove ‘query_and_fetch’ and
‘df_query_and_fetch’ as options
- Removes documentation for these options
Closes#9606
This commit brings the benefits of the `count` search type to search requests
that have a `size` of 0:
- a single round-trip to shards (no fetch phase)
- ability to use the query cache
Since `count` now provides no benefits over `query_then_fetch`, it has been
deprecated.
Close#7630
The behaviour is better in the case someone has multiple levels of nested object fields defined in the mapping and like to define a single inner_hits definition that is two or more levels deep.
If someone wants inner hits on a nested field that is 2 levels deep the following would need to be defined:
```
{
...
"inner_hits" : {
"path" : {
"level1" : {
"inner_hits" : {
"path" : {
"level2" : {
"query" : { .... }
}
}
}
}
}
}
}
```
With this change the above can be defined as:
```
{
...
"inner_hits" : {
"path" : {
"level1.level2" : {
"query" : { .... }
}
}
}
}
```
Closes#9251
Changed search_type docs to reflect that the `(dfs_)query_and_fetch` modes are an internal optimization and should not be specified explicitly by the user.
Relates to #9606
We now have a very useful annotation to mark features or parameters as
experimental. Let's use it! This commit replaces some custom text warnings with
this annotation and adds this annotation to some existing features/parameters:
- inner_hits (unreleased yet)
- terminate_after (released in 1.4)
- per-bucket doc count errors in the terms agg (released in 1.4)
I also tagged with this annotation settings which should either be not needed
(like the ability to evict entries from the filter cache based on time) or that
are too deep into the way that Elasticsearch works like the Directory
implementation or merge settings.
Close#9563
Inner hits allows to embed nested inner objects, children documents or the parent document that contributed to the matching of the returned search hit as inner hits, which would otherwise be hidden.
Closes#8153Closes#3022Closes#3152
This is functionally equivalent to before, so there should be no
user-visible impact, except I added a NOTE in the docs warning about
the interaction of pagination and rescoring.
Closes#6232Closes#7707
Aggregations are collection-wide statistics, which is incompatible with the
collection mode of search_type=SCAN since it doesn't collect all matches on
calls to the search API.
Close#7429
Aggregations are collection-wide statistics so they would always be the same.
In order to save CPU/bandwidth, we can just return them on the first page.
Same as #1642 but for aggregations.
Because json objects are unordered this also adds an explicit order syntax
that looks like
"highlight": {
"fields": [
{"title":{ /*params*/ }},
{"text":{ /*params*/ }}
]
}
This is not useful for any of the builtin highlighters but will be useful
in plugins.
Closes#4649
Jim Ferenczi
Clinton Gormley
maciejkula
Masaru Hasegawa
Adrin Jalali
Craig Squire
Joshua Rich
Adrien Grand
Jason Tedor
Joshua Rich
Nik Everett
Tobias Günther
Gytis Šk
Isabel Drost-Fromm
Isabel Drost-Fromm
Robert Muir
Robert Muir
Martijn van Groningen
Britta Weber
Jeff
Dongjoon Hyun
Simon Willnauer
Jason Bryan
Shintaro Kaneko
Jamie McCarthy
javanna
Thomas Cucchietti
Michael McCandless
Lee Hinman
markharwood
Ruslan Boyarskiy
Nirmal Chidambaram
Andreas Kohn
Colin Goodheart-Smithe
Jack Conradson
Andrew Selden
Pascal Borreli
aleph-zero
Mehdi Mollaverdi
Jun Ohtani
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