Common options
editCommon options
editAll Elasticsearch REST APIs support the following options.
Pretty Results
editWhen appending ?pretty=true
to any request made, the JSON returned
will be pretty formatted (use it for debugging only!). Another option is
to set ?format=yaml
which will cause the result to be returned in the
(sometimes) more readable yaml format.
Human readable output
editStatistics are returned in a format suitable for humans
(e.g. "exists_time": "1h"
or "size": "1kb"
) and for computers
(e.g. "exists_time_in_millis": 3600000
or "size_in_bytes": 1024
).
The human readable values can be turned off by adding ?human=false
to the query string. This makes sense when the stats results are
being consumed by a monitoring tool, rather than intended for human
consumption. The default for the human
flag is
false
.
Date Math
editMost parameters which accept a formatted date value — such as gt
and lt
in range
queries, or from
and to
in daterange
aggregations — understand date maths.
The expression starts with an anchor date, which can either be now
, or a
date string ending with ||
. This anchor date can optionally be followed by
one or more maths expressions:
-
+1h
: Add one hour -
-1d
: Subtract one day -
/d
: Round down to the nearest day
The supported time units differ from those supported by time units for durations. The supported units are:
|
Years |
|
Months |
|
Weeks |
|
Days |
|
Hours |
|
Hours |
|
Minutes |
|
Seconds |
Assuming now
is 2001-01-01 12:00:00
, some examples are:
|
|
|
|
|
|
|
|
Response Filtering
editAll REST APIs accept a filter_path
parameter that can be used to reduce
the response returned by Elasticsearch. This parameter takes a comma
separated list of filters expressed with the dot notation:
response = client.search( q: 'kimchy', filter_path: 'took,hits.hits._id,hits.hits._score' ) puts response
GET /_search?q=kimchy&filter_path=took,hits.hits._id,hits.hits._score
Responds:
{ "took" : 3, "hits" : { "hits" : [ { "_id" : "0", "_score" : 1.6375021 } ] } }
It also supports the *
wildcard character to match any field or part
of a field’s name:
$response = $client->cluster()->state();
response = client.cluster.state( filter_path: 'metadata.indices.*.stat*' ) puts response
res, err := es.Cluster.State( es.Cluster.State.WithFilterPath("metadata.indices.*.stat*"), ) fmt.Println(res, err)
const response = await client.cluster.state({ filter_path: 'metadata.indices.*.stat*' }) console.log(response)
GET /_cluster/state?filter_path=metadata.indices.*.stat*
Responds:
{ "metadata" : { "indices" : { "my-index-000001": {"state": "open"} } } }
And the **
wildcard can be used to include fields without knowing the
exact path of the field. For example, we can return the state
of every shard with this request:
$response = $client->cluster()->state();
response = client.cluster.state( filter_path: 'routing_table.indices.**.state' ) puts response
res, err := es.Cluster.State( es.Cluster.State.WithFilterPath("routing_table.indices.**.state"), ) fmt.Println(res, err)
const response = await client.cluster.state({ filter_path: 'routing_table.indices.**.state' }) console.log(response)
GET /_cluster/state?filter_path=routing_table.indices.**.state
Responds:
{ "routing_table": { "indices": { "my-index-000001": { "shards": { "0": [{"state": "STARTED"}, {"state": "UNASSIGNED"}] } } } } }
It is also possible to exclude one or more fields by prefixing the filter with the char -
:
$response = $client->count();
response = client.count( filter_path: '-_shards' ) puts response
res, err := es.Count( es.Count.WithFilterPath("-_shards"), es.Count.WithPretty(), ) fmt.Println(res, err)
const response = await client.count({ filter_path: '-_shards' }) console.log(response)
GET /_count?filter_path=-_shards
Responds:
{ "count" : 5 }
And for more control, both inclusive and exclusive filters can be combined in the same expression. In this case, the exclusive filters will be applied first and the result will be filtered again using the inclusive filters:
$response = $client->cluster()->state();
response = client.cluster.state( filter_path: 'metadata.indices.*.state,-metadata.indices.logstash-*' ) puts response
res, err := es.Cluster.State( es.Cluster.State.WithFilterPath("metadata.indices.*.state,-metadata.indices.logstash-*"), ) fmt.Println(res, err)
const response = await client.cluster.state({ filter_path: 'metadata.indices.*.state,-metadata.indices.logstash-*' }) console.log(response)
GET /_cluster/state?filter_path=metadata.indices.*.state,-metadata.indices.logstash-*
Responds:
{ "metadata" : { "indices" : { "my-index-000001" : {"state" : "open"}, "my-index-000002" : {"state" : "open"}, "my-index-000003" : {"state" : "open"} } } }
Note that Elasticsearch sometimes returns directly the raw value of a field,
like the _source
field. If you want to filter _source
fields, you should
consider combining the already existing _source
parameter (see
Get API for more details) with the filter_path
parameter like this:
$params = [ 'index' => 'library', 'body' => [ 'title' => 'Book #1', 'rating' => 200.1, ], ]; $response = $client->index($params); $params = [ 'index' => 'library', 'body' => [ 'title' => 'Book #2', 'rating' => 1.7, ], ]; $response = $client->index($params); $params = [ 'index' => 'library', 'body' => [ 'title' => 'Book #3', 'rating' => 0.1, ], ]; $response = $client->index($params); $response = $client->search();
response = client.index( index: 'library', refresh: true, body: { title: 'Book #1', rating: 200.1 } ) puts response response = client.index( index: 'library', refresh: true, body: { title: 'Book #2', rating: 1.7 } ) puts response response = client.index( index: 'library', refresh: true, body: { title: 'Book #3', rating: 0.1 } ) puts response response = client.search( filter_path: 'hits.hits._source', _source: 'title', sort: 'rating:desc' ) puts response
{ res, err := es.Index( "library", strings.NewReader(`{ "title": "Book #1", "rating": 200.1 }`), es.Index.WithRefresh("true"), es.Index.WithPretty(), ) fmt.Println(res, err) } { res, err := es.Index( "library", strings.NewReader(`{ "title": "Book #2", "rating": 1.7 }`), es.Index.WithRefresh("true"), es.Index.WithPretty(), ) fmt.Println(res, err) } { res, err := es.Index( "library", strings.NewReader(`{ "title": "Book #3", "rating": 0.1 }`), es.Index.WithRefresh("true"), es.Index.WithPretty(), ) fmt.Println(res, err) } { res, err := es.Search( es.Search.WithSource("title"), es.Search.WithFilterPath("hits.hits._source"), es.Search.WithSort("rating:desc"), es.Search.WithPretty(), ) fmt.Println(res, err) }
const response0 = await client.index({ index: 'library', refresh: true, body: { title: 'Book #1', rating: 200.1 } }) console.log(response0) const response1 = await client.index({ index: 'library', refresh: true, body: { title: 'Book #2', rating: 1.7 } }) console.log(response1) const response2 = await client.index({ index: 'library', refresh: true, body: { title: 'Book #3', rating: 0.1 } }) console.log(response2) const response3 = await client.search({ filter_path: 'hits.hits._source', _source: 'title', sort: 'rating:desc' }) console.log(response3)
POST /library/_doc?refresh {"title": "Book #1", "rating": 200.1} POST /library/_doc?refresh {"title": "Book #2", "rating": 1.7} POST /library/_doc?refresh {"title": "Book #3", "rating": 0.1} GET /_search?filter_path=hits.hits._source&_source=title&sort=rating:desc
{ "hits" : { "hits" : [ { "_source":{"title":"Book #1"} }, { "_source":{"title":"Book #2"} }, { "_source":{"title":"Book #3"} } ] } }
Flat Settings
editThe flat_settings
flag affects rendering of the lists of settings. When the
flat_settings
flag is true
, settings are returned in a flat format:
response = client.indices.get_settings( index: 'my-index-000001', flat_settings: true ) puts response
GET my-index-000001/_settings?flat_settings=true
Returns:
{ "my-index-000001" : { "settings": { "index.number_of_replicas": "1", "index.number_of_shards": "1", "index.creation_date": "1474389951325", "index.uuid": "n6gzFZTgS664GUfx0Xrpjw", "index.version.created": ..., "index.routing.allocation.include._tier_preference" : "data_content", "index.provided_name" : "my-index-000001" } } }
When the flat_settings
flag is false
, settings are returned in a more
human readable structured format:
response = client.indices.get_settings( index: 'my-index-000001', flat_settings: false ) puts response
GET my-index-000001/_settings?flat_settings=false
Returns:
{ "my-index-000001" : { "settings" : { "index" : { "number_of_replicas": "1", "number_of_shards": "1", "creation_date": "1474389951325", "uuid": "n6gzFZTgS664GUfx0Xrpjw", "version": { "created": ... }, "routing": { "allocation": { "include": { "_tier_preference": "data_content" } } }, "provided_name" : "my-index-000001" } } } }
By default flat_settings
is set to false
.
Fuzziness
editSome queries and APIs support parameters to allow inexact fuzzy matching,
using the fuzziness
parameter.
When querying text
or keyword
fields, fuzziness
is interpreted as a
Levenshtein Edit Distance — the number of one character changes that need to be made to one string to
make it the same as another string.
The fuzziness
parameter can be specified as:
|
The maximum allowed Levenshtein Edit Distance (or number of edits) |
|
Generates an edit distance based on the length of the term.
Low and high distance arguments may be optionally provided
|
Enabling stack traces
editBy default when a request returns an error Elasticsearch doesn’t include the
stack trace of the error. You can enable that behavior by setting the
error_trace
url parameter to true
. For example, by default when you send an
invalid size
parameter to the _search
API:
POST /my-index-000001/_search?size=surprise_me
The response looks like:
{ "error" : { "root_cause" : [ { "type" : "illegal_argument_exception", "reason" : "Failed to parse int parameter [size] with value [surprise_me]" } ], "type" : "illegal_argument_exception", "reason" : "Failed to parse int parameter [size] with value [surprise_me]", "caused_by" : { "type" : "number_format_exception", "reason" : "For input string: \"surprise_me\"" } }, "status" : 400 }
But if you set error_trace=true
:
POST /my-index-000001/_search?size=surprise_me&error_trace=true
The response looks like:
{ "error": { "root_cause": [ { "type": "illegal_argument_exception", "reason": "Failed to parse int parameter [size] with value [surprise_me]", "stack_trace": "Failed to parse int parameter [size] with value [surprise_me]]; nested: IllegalArgumentException..." } ], "type": "illegal_argument_exception", "reason": "Failed to parse int parameter [size] with value [surprise_me]", "stack_trace": "java.lang.IllegalArgumentException: Failed to parse int parameter [size] with value [surprise_me]\n at org.elasticsearch.rest.RestRequest.paramAsInt(RestRequest.java:175)...", "caused_by": { "type": "number_format_exception", "reason": "For input string: \"surprise_me\"", "stack_trace": "java.lang.NumberFormatException: For input string: \"surprise_me\"\n at java.lang.NumberFormatException.forInputString(NumberFormatException.java:65)..." } }, "status": 400 }