OpenSearch/docs/reference/indices/analyze.asciidoc

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[[indices-analyze]]
== Analyze
Performs the analysis process on a text and return the tokens breakdown
of the text.
Can be used without specifying an index against one of the many built in
analyzers:
[source,js]
--------------------------------------------------
curl -XGET 'localhost:9200/_analyze' -d '
{
"analyzer" : "standard",
"text" : "this is a test"
}'
--------------------------------------------------
If text parameter is provided as array of strings, it is analyzed as a multi-valued field.
[source,js]
--------------------------------------------------
curl -XGET 'localhost:9200/_analyze' -d '
{
"analyzer" : "standard",
"text" : ["this is a test", "the second text"]
}'
--------------------------------------------------
Or by building a custom transient analyzer out of tokenizers,
token filters and char filters. Token filters can use the shorter 'filter'
parameter name:
[source,js]
--------------------------------------------------
curl -XGET 'localhost:9200/_analyze' -d '
{
"tokenizer" : "keyword",
"filter" : ["lowercase"],
"text" : "this is a test"
}'
curl -XGET 'localhost:9200/_analyze' -d '
{
"tokenizer" : "keyword",
"token_filter" : ["lowercase"],
"char_filter" : ["html_strip"],
"text" : "this is a <b>test</b>"
}'
--------------------------------------------------
deprecated[5.0.0, Use `filter`/`token_filter`/`char_filter` instead of `filters`/`token_filters`/`char_filters`]
Custom tokenizers, token filters, and character filters can be specified in the request body as follows:
[source,js]
--------------------------------------------------
curl -XGET 'localhost:9200/_analyze' -d '
{
"tokenizer" : "whitespace",
"filter" : ["lowercase", {"type": "stop", "stopwords": ["a", "is", "this"]}],
"text" : "this is a test"
}'
--------------------------------------------------
It can also run against a specific index:
[source,js]
--------------------------------------------------
curl -XGET 'localhost:9200/test/_analyze' -d '
{
"text" : "this is a test"
}'
--------------------------------------------------
The above will run an analysis on the "this is a test" text, using the
default index analyzer associated with the `test` index. An `analyzer`
can also be provided to use a different analyzer:
[source,js]
--------------------------------------------------
curl -XGET 'localhost:9200/test/_analyze' -d '
{
"analyzer" : "whitespace",
"text" : "this is a test"
}'
--------------------------------------------------
Also, the analyzer can be derived based on a field mapping, for example:
[source,js]
--------------------------------------------------
curl -XGET 'localhost:9200/test/_analyze' -d '
{
"field" : "obj1.field1",
"text" : "this is a test"
}'
--------------------------------------------------
Will cause the analysis to happen based on the analyzer configured in the
mapping for `obj1.field1` (and if not, the default index analyzer).
All parameters can also supplied as request parameters. For example:
[source,js]
--------------------------------------------------
curl -XGET 'localhost:9200/_analyze?tokenizer=keyword&filter=lowercase&text=this+is+a+test'
--------------------------------------------------
For backwards compatibility, we also accept the text parameter as the body of the request,
provided it doesn't start with `{` :
[source,js]
--------------------------------------------------
curl -XGET 'localhost:9200/_analyze?tokenizer=keyword&token_filter=lowercase&char_filter=html_strip' -d 'this is a <b>test</b>'
--------------------------------------------------
=== Explain Analyze
If you want to get more advanced details, set `explain` to `true` (defaults to `false`). It will output all token attributes for each token.
You can filter token attributes you want to output by setting `attributes` option.
experimental[The format of the additional detail information is experimental and can change at any time]
[source,js]
--------------------------------------------------
GET _analyze
{
"tokenizer" : "standard",
"token_filter" : ["snowball"],
"text" : "detailed output",
"explain" : true,
"attributes" : ["keyword"] <1>
}
--------------------------------------------------
// CONSOLE
<1> Set "keyword" to output "keyword" attribute only
coming[2.0.0, body based parameters were added in 2.0.0]
The request returns the following result:
[source,js]
--------------------------------------------------
{
"detail" : {
"custom_analyzer" : true,
"charfilters" : [ ],
"tokenizer" : {
"name" : "standard",
"tokens" : [ {
"token" : "detailed",
"start_offset" : 0,
"end_offset" : 8,
"type" : "<ALPHANUM>",
"position" : 0
}, {
"token" : "output",
"start_offset" : 9,
"end_offset" : 15,
"type" : "<ALPHANUM>",
"position" : 1
} ]
},
"tokenfilters" : [ {
"name" : "snowball",
"tokens" : [ {
"token" : "detail",
"start_offset" : 0,
"end_offset" : 8,
"type" : "<ALPHANUM>",
"position" : 0,
"keyword" : false <1>
}, {
"token" : "output",
"start_offset" : 9,
"end_offset" : 15,
"type" : "<ALPHANUM>",
"position" : 1,
"keyword" : false <1>
} ]
} ]
}
}
--------------------------------------------------
<1> Output only "keyword" attribute, since specify "attributes" in the request.