Requires field index_options set to "offsets" in order to store positions and offsets in the postings list.
Considerably faster than the plain highlighter since it doesn't require to reanalyze the text to be highlighted: the larger the documents the better the performance gain should be.
Requires less disk space than term_vectors, needed for the fast_vector_highlighter.
Breaks the text into sentences and highlights them. Uses a BreakIterator to find sentences in the text. Plays really well with natural text, not quite the same if the text contains html markup for instance.
Treats the document as the whole corpus, and scores individual sentences as if they were documents in this corpus, using the BM25 algorithm.
Uses forked version of lucene postings highlighter to support:
- per value discrete highlighting for fields that have multiple values, needed when number_of_fragments=0 since we want to return a snippet per value
- manually passing in query terms to avoid calling extract terms multiple times, since we use a different highlighter instance per doc/field, but the query is always the same
The lucene postings highlighter api is quite different compared to the existing highlighters api, the main difference being that it allows to highlight multiple fields in multiple docs with a single call, ensuring sequential IO.
The way it is introduced in elasticsearch in this first round is a compromise trying not to change the current highlight api, which works per document, per field. The main disadvantage is that we lose the sequential IO, but we can always refactor the highlight api to work with multiple documents.
Supports pre_tag, post_tag, number_of_fragments (0 highlights the whole field), require_field_match, no_match_size, order by score and html encoding.
Closes#3704
You can configure the highlighting api to return an excerpt of a field
even if there wasn't a match on the field.
The FVH makes excerpts from the beginning of the string to the first
boundary character after the requested length or the boundary_max_scan,
whichever comes first. The Plain highlighter makes excerpts from the
beginning of the string to the end of the last token before the requested
length.
Closes#1171
Currently we have a marker interface for Acknowledged[Request|Response],
this makes not much sense since we duplicate the code in each subclass
or class that implements the interface. We can simply use abstract
classes and have it implemented only once.
This commit primarily folds [Double|Bytes|Long|GeoPoint]Values.Iter
into [Double|Bytes|Long|GeoPoint]Values. Iterations now don't require
a auxillary class (Iter) but instead driven by native for loops. All
[Double|Bytes|Long|GeoPoint]Values are stateful and provide `setDocId`
and `nextValue` methods to iterate over all values in a document.
This has several advantage:
* The amout of specialized classes is reduced
* Iteration is clearly stateful ie. Iters can't be confused to be local.
* All iterations are size bounded which prevents runtime checks and
allows JIT optimizations / loop un-rolling and most iterations are
branch free.
* Due to the bounded iteration the need for a `hasNext` method call
is removed.
* Value iterations feels more native.
This commit also adds consistent documentation and unifies the calcualtion
if SortMode is involved.
This commit also changes the runtime behavior of BytesValues#getValue() such that it
will never return `null` anymore. If a document has no value in a field
this method still returns a `BytesRef` with a `length` of 0. To identify
documents with no values #hasValue() or #setDocument(int) should be used.
The latter should be preferred if the value will be consumed in the case
the document has a value.
Have a separate channel for recovery, so it won't overflow the "low" channel which is also used for bulk indexing.
Also, rename the channel names to be more descriptive. Change low to bulk (for bulk based operations, currently just bulk indexing), med to reg (for "regular" operations), and high to state (for state based communication). The new channel for recovery will be named recovery, and the ping channel will remain the same.
closes#3954
When setting track scores, the scan search type will return the scores for each document. The Java API builder does not properly set this value (it only sets it if a sort in in place, which is not relevant for scan search type).
closes#3949
The description of the timeout parameter was worded misleadingly; it implied that the API would wait until the cluster reached the desired level and then stayed at that level for the timeout. I've tweaked the sentence to remove the risk of confusion.
Currently we don't allow resetting the awareness
attribute via the API since it requires at least one
non-empty string to update the setting. This commit
allows resetting this using an empty string.
Closes#3931
The #3526 fix was not complete, it handled cases of on node execution, but didn't properly handle cases where it was executed over the network, and forcing the execution of the replica operation when done over the wire.
This relates to #3854closes#3929
Added new AckedClusterStateUpdateTask interface that can be used to submit cluster state update tasks and allows actions to be notified back when a set of (configurable) nodes have acknowledged the cluster state update. Supports a configurable timeout, so that we wait for acknowledgement for a limited amount of time (will be provided in the request as it curently happens, default 10s).
Internally, a low level AckListener is created (InternalClusterService) and passed to the publish method, so that it can be notified whenever each node responds to the publish request. Once all the expected nodes have responded or the timeoeout has expired, the AckListener notifies the action which will return adding the proper acknowledged flag to the response.
Ideally, this new mechanism will gradually replace the existing ones based on custom endpoints and notifications (per api).
Closes#3786
The suggest stop filter is an improved version of the stop filter, which
takes stopwords only into account if the last char of a query is a
whitespace. This allows you to keep stopwords, but to allow suggesting for
"a".
Example: Index document content "a word". You are now able to suggest for
"a" and get back results in the completion suggester, if the suggest stop
filter is used on the query side, but will not get back any results for
"a " as this is identified as a stopword.
The implementation allows to set the `remove_trailing` parameter for a
custom stop filter and thus use the suggest stop filter instead of the
standard stop filter.