- Elasticsearch Guide: other versions:
- Elasticsearch introduction
- Getting started with Elasticsearch
- Set up Elasticsearch
- Installing Elasticsearch
- Configuring Elasticsearch
- Important Elasticsearch configuration
- Important System Configuration
- Bootstrap Checks
- Heap size check
- File descriptor check
- Memory lock check
- Maximum number of threads check
- Max file size check
- Maximum size virtual memory check
- Maximum map count check
- Client JVM check
- Use serial collector check
- System call filter check
- OnError and OnOutOfMemoryError checks
- Early-access check
- G1GC check
- All permission check
- Discovery configuration check
- Starting Elasticsearch
- Stopping Elasticsearch
- Adding nodes to your cluster
- Set up X-Pack
- Configuring X-Pack Java Clients
- Bootstrap Checks for X-Pack
- Upgrade Elasticsearch
- API conventions
- Document APIs
- Search APIs
- Aggregations
- Metrics Aggregations
- Avg Aggregation
- Weighted Avg Aggregation
- Cardinality Aggregation
- Extended Stats Aggregation
- Geo Bounds Aggregation
- Geo Centroid Aggregation
- Max Aggregation
- Min Aggregation
- Percentiles Aggregation
- Percentile Ranks Aggregation
- Scripted Metric Aggregation
- Stats Aggregation
- Sum Aggregation
- Top Hits Aggregation
- Value Count Aggregation
- Median Absolute Deviation Aggregation
- Bucket Aggregations
- Adjacency Matrix Aggregation
- Auto-interval Date Histogram Aggregation
- Children Aggregation
- Composite Aggregation
- Date Histogram Aggregation
- Date Range Aggregation
- Diversified Sampler Aggregation
- Filter Aggregation
- Filters Aggregation
- Geo Distance Aggregation
- GeoHash grid Aggregation
- GeoTile Grid Aggregation
- Global Aggregation
- Histogram Aggregation
- IP Range Aggregation
- Missing Aggregation
- Nested Aggregation
- Parent Aggregation
- Range Aggregation
- Reverse nested Aggregation
- Sampler Aggregation
- Significant Terms Aggregation
- Significant Text Aggregation
- Terms Aggregation
- Pipeline Aggregations
- Avg Bucket Aggregation
- Derivative Aggregation
- Max Bucket Aggregation
- Min Bucket Aggregation
- Sum Bucket Aggregation
- Stats Bucket Aggregation
- Extended Stats Bucket Aggregation
- Percentiles Bucket Aggregation
- Moving Average Aggregation
- Moving Function Aggregation
- Cumulative Sum Aggregation
- Bucket Script Aggregation
- Bucket Selector Aggregation
- Bucket Sort Aggregation
- Serial Differencing Aggregation
- Matrix Aggregations
- Caching heavy aggregations
- Returning only aggregation results
- Aggregation Metadata
- Returning the type of the aggregation
- Metrics Aggregations
- Indices APIs
- Create Index
- Delete Index
- Get Index
- Indices Exists
- Open / Close Index API
- Shrink Index
- Split Index
- Rollover Index
- Put Mapping
- Get Mapping
- Get Field Mapping
- Types Exists
- Index Aliases
- Update Indices Settings
- Get Settings
- Analyze
- Index Templates
- Indices Stats
- Indices Segments
- Indices Recovery
- Indices Shard Stores
- Clear Cache
- Flush
- Refresh
- Force Merge
- cat APIs
- Cluster APIs
- Query DSL
- Scripting
- Mapping
- Analysis
- Anatomy of an analyzer
- Testing analyzers
- Analyzers
- Normalizers
- Tokenizers
- Standard Tokenizer
- Letter Tokenizer
- Lowercase Tokenizer
- Whitespace Tokenizer
- UAX URL Email Tokenizer
- Classic Tokenizer
- Thai Tokenizer
- NGram Tokenizer
- Edge NGram Tokenizer
- Keyword Tokenizer
- Pattern Tokenizer
- Char Group Tokenizer
- Simple Pattern Tokenizer
- Simple Pattern Split Tokenizer
- Path Hierarchy Tokenizer
- Path Hierarchy Tokenizer Examples
- Token Filters
- ASCII Folding Token Filter
- Flatten Graph Token Filter
- Length Token Filter
- Lowercase Token Filter
- Uppercase Token Filter
- NGram Token Filter
- Edge NGram Token Filter
- Porter Stem Token Filter
- Shingle Token Filter
- Stop Token Filter
- Word Delimiter Token Filter
- Word Delimiter Graph Token Filter
- Multiplexer Token Filter
- Conditional Token Filter
- Predicate Token Filter Script
- Stemmer Token Filter
- Stemmer Override Token Filter
- Keyword Marker Token Filter
- Keyword Repeat Token Filter
- KStem Token Filter
- Snowball Token Filter
- Phonetic Token Filter
- Synonym Token Filter
- Parsing synonym files
- Synonym Graph Token Filter
- Compound Word Token Filters
- Reverse Token Filter
- Elision Token Filter
- Truncate Token Filter
- Unique Token Filter
- Pattern Capture Token Filter
- Pattern Replace Token Filter
- Trim Token Filter
- Limit Token Count Token Filter
- Hunspell Token Filter
- Common Grams Token Filter
- Normalization Token Filter
- CJK Width Token Filter
- CJK Bigram Token Filter
- Delimited Payload Token Filter
- Keep Words Token Filter
- Keep Types Token Filter
- Exclude mode settings example
- Classic Token Filter
- Apostrophe Token Filter
- Decimal Digit Token Filter
- Fingerprint Token Filter
- Minhash Token Filter
- Remove Duplicates Token Filter
- Character Filters
- Modules
- Index modules
- Ingest node
- Pipeline Definition
- Ingest APIs
- Accessing Data in Pipelines
- Conditional Execution in Pipelines
- Handling Failures in Pipelines
- Processors
- Append Processor
- Bytes Processor
- Convert Processor
- Date Processor
- Date Index Name Processor
- Dissect Processor
- Dot Expander Processor
- Drop Processor
- Fail Processor
- Foreach Processor
- GeoIP Processor
- Grok Processor
- Gsub Processor
- Join Processor
- JSON Processor
- KV Processor
- Lowercase Processor
- Pipeline Processor
- Remove Processor
- Rename Processor
- Script Processor
- Set Processor
- Set Security User Processor
- Split Processor
- Sort Processor
- Trim Processor
- Uppercase Processor
- URL Decode Processor
- User Agent processor
- Managing the index lifecycle
- Getting started with index lifecycle management
- Policy phases and actions
- Set up index lifecycle management policy
- Using policies to manage index rollover
- Update policy
- Index lifecycle error handling
- Restoring snapshots of managed indices
- Start and stop index lifecycle management
- Using ILM with existing indices
- SQL access
- Monitor a cluster
- Rolling up historical data
- Frozen indices
- Set up a cluster for high availability
- X-Pack APIs
- Info API
- Cross-cluster replication APIs
- Explore API
- Freeze index
- Index lifecycle management API
- Licensing APIs
- Migration APIs
- Machine learning APIs
- Add events to calendar
- Add jobs to calendar
- Close jobs
- Create calendar
- Create datafeeds
- Create filter
- Create jobs
- Delete calendar
- Delete datafeeds
- Delete events from calendar
- Delete filter
- Delete forecast
- Delete jobs
- Delete jobs from calendar
- Delete model snapshots
- Delete expired data
- Find file structure
- Flush jobs
- Forecast jobs
- Get calendars
- Get buckets
- Get overall buckets
- Get categories
- Get datafeeds
- Get datafeed statistics
- Get influencers
- Get jobs
- Get job statistics
- Get machine learning info
- Get model snapshots
- Get scheduled events
- Get filters
- Get records
- Open jobs
- Post data to jobs
- Preview datafeeds
- Revert model snapshots
- Set upgrade mode
- Start datafeeds
- Stop datafeeds
- Update datafeeds
- Update filter
- Update jobs
- Update model snapshots
- Rollup APIs
- Security APIs
- Authenticate
- Change passwords
- Clear cache
- Clear roles cache
- Create API keys
- Create or update application privileges
- Create or update role mappings
- Create or update roles
- Create or update users
- Delete application privileges
- Delete role mappings
- Delete roles
- Delete users
- Disable users
- Enable users
- Get API key information
- Get application privileges
- Get role mappings
- Get roles
- Get token
- Get users
- Has privileges
- Invalidate API key
- Invalidate token
- SSL certificate
- Unfreeze index
- Watcher APIs
- Definitions
- Secure a cluster
- Overview
- Configuring security
- Encrypting communications in Elasticsearch
- Encrypting communications in an Elasticsearch Docker Container
- Enabling cipher suites for stronger encryption
- Separating node-to-node and client traffic
- Configuring an Active Directory realm
- Configuring a file realm
- Configuring an LDAP realm
- Configuring a native realm
- Configuring a PKI realm
- Configuring a SAML realm
- Configuring a Kerberos realm
- FIPS 140-2
- Security files
- How security works
- User authentication
- Built-in users
- Internal users
- Token-based authentication services
- Realms
- Realm chains
- Active Directory user authentication
- File-based user authentication
- LDAP user authentication
- Native user authentication
- PKI user authentication
- SAML authentication
- Kerberos authentication
- Integrating with other authentication systems
- Enabling anonymous access
- Controlling the user cache
- Configuring SAML single-sign-on on the Elastic Stack
- User authorization
- Auditing security events
- Encrypting communications
- Restricting connections with IP filtering
- Cross cluster search, clients, and integrations
- Tutorial: Getting started with security
- Tutorial: Encrypting communications
- Troubleshooting
- Some settings are not returned via the nodes settings API
- Authorization exceptions
- Users command fails due to extra arguments
- Users are frequently locked out of Active Directory
- Certificate verification fails for curl on Mac
- SSLHandshakeException causes connections to fail
- Common SSL/TLS exceptions
- Common Kerberos exceptions
- Common SAML issues
- Internal Server Error in Kibana
- Setup-passwords command fails due to connection failure
- Failures due to relocation of the configuration files
- Limitations
- Alerting on cluster and index events
- Command line tools
- How To
- Testing
- Glossary of terms
- Release highlights
- Breaking changes
- Release notes
Common options
editCommon options
editThe following options can be applied to all of the REST APIs.
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:
GET /_search?q=elasticsearch&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:
GET /_cluster/state?filter_path=metadata.indices.*.stat*
Responds:
{ "metadata" : { "indices" : { "twitter": {"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 Lucene version
of every segment with this request:
GET /_cluster/state?filter_path=routing_table.indices.**.state
Responds:
{ "routing_table": { "indices": { "twitter": { "shards": { "0": [{"state": "STARTED"}, {"state": "UNASSIGNED"}] } } } } }
It is also possible to exclude one or more fields by prefixing the filter with the char -
:
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:
GET /_cluster/state?filter_path=metadata.indices.*.state,-metadata.indices.logstash-*
Responds:
{ "metadata" : { "indices" : { "index-1" : {"state" : "open"}, "index-2" : {"state" : "open"}, "index-3" : {"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:
POST /library/book?refresh {"title": "Book #1", "rating": 200.1} POST /library/book?refresh {"title": "Book #2", "rating": 1.7} POST /library/book?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:
GET twitter/_settings?flat_settings=true
Returns:
{ "twitter" : { "settings": { "index.number_of_replicas": "1", "index.number_of_shards": "1", "index.creation_date": "1474389951325", "index.uuid": "n6gzFZTgS664GUfx0Xrpjw", "index.version.created": ..., "index.provided_name" : "twitter" } } }
When the flat_settings
flag is false
, settings are returned in a more
human readable structured format:
GET twitter/_settings?flat_settings=false
Returns:
{ "twitter" : { "settings" : { "index" : { "number_of_replicas": "1", "number_of_shards": "1", "creation_date": "1474389951325", "uuid": "n6gzFZTgS664GUfx0Xrpjw", "version": { "created": ... }, "provided_name" : "twitter" } } } }
By default flat_settings
is set to false
.
Parameters
editRest parameters (when using HTTP, map to HTTP URL parameters) follow the convention of using underscore casing.
Boolean Values
editAll REST API parameters (both request parameters and JSON body) support
providing boolean "false" as the value false
and boolean "true" as the
value true
. All other values will raise an error.
Number Values
editAll REST APIs support providing numbered parameters as string
on top
of supporting the native JSON number types.
Time units
editWhenever durations need to be specified, e.g. for a timeout
parameter, the duration must specify
the unit, like 2d
for 2 days. The supported units are:
|
Days |
|
Hours |
|
Minutes |
|
Seconds |
|
Milliseconds |
|
Microseconds |
|
Nanoseconds |
Byte size units
editWhenever the byte size of data needs to be specified, e.g. when setting a buffer size
parameter, the value must specify the unit, like 10kb
for 10 kilobytes. Note that
these units use powers of 1024, so 1kb
means 1024 bytes. The supported units are:
|
Bytes |
|
Kilobytes |
|
Megabytes |
|
Gigabytes |
|
Terabytes |
|
Petabytes |
Unit-less quantities
editUnit-less quantities means that they don’t have a "unit" like "bytes" or "Hertz" or "meter" or "long tonne".
If one of these quantities is large we’ll print it out like 10m for 10,000,000 or 7k for 7,000. We’ll still print 87 when we mean 87 though. These are the supported multipliers:
|
Kilo |
|
Mega |
|
Giga |
|
Tera |
|
Peta |
Distance Units
editWherever distances need to be specified, such as the distance
parameter in
the Geo-distance), the default unit is meters if none is specified.
Distances can be specified in other units, such as "1km"
or
"2mi"
(2 miles).
The full list of units is listed below:
Mile |
|
Yard |
|
Feet |
|
Inch |
|
Kilometer |
|
Meter |
|
Centimeter |
|
Millimeter |
|
Nautical mile |
|
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 /twitter/_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 /twitter/_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 }
Request body in query string
editFor libraries that don’t accept a request body for non-POST requests,
you can pass the request body as the source
query string parameter
instead. When using this method, the source_content_type
parameter
should also be passed with a media type value that indicates the format
of the source, such as application/json
.
Content-Type Requirements
editThe type of the content sent in a request body must be specified using
the Content-Type
header. The value of this header must map to one of
the supported formats that the API supports. Most APIs support JSON,
YAML, CBOR, and SMILE. The bulk and multi-search APIs support NDJSON,
JSON, and SMILE; other types will result in an error response.
Additionally, when using the source
query string parameter, the
content type must be specified using the source_content_type
query
string parameter.
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