ElasticSearch 2 (5) - Document APIs
ElasticSearch 2.1.1 (5) - Document APIs
This section describes the following CRUD APIs:
Single document APIs
Index API
Query:
$ curl -XPUT 'http://localhost:9200/twitter/tweet/1' -d '{
"user" : "kimchy",
"post_date" : "2009-11-15T14:12:12",
"message" : "trying out Elasticsearch"
}'
Result:
{
"_shards" : {
"total" : 10,
"failed" : 0,
"successful" : 10
},
"_index" : "twitter",
"_type" : "tweet",
"_id" : "1",
"_version" : 1,
"created" : true
}
-
total -
Indicates to how many shard copies (primary and replica shards) the index operation should be executed on.
-
successful -
Indicates the number of shard copies the index operation succeeded on.
-
failures -
An array that contains replication related errors in the case an index operation failed on a replica shard.
Replica shards may not all be started when an indexing operation successfully returns (by default, a quorum is required). In that case, total will be equal to the total shards based on the index replica settings and successful will be equal to the number of shards started (primary plus replicas). As there were no failures, the failed will be 0.
Automatic Index Creation
-
Automatic index creation disable
action.auto_create_index => false
-
Automatic mapping(type) creation disable
index.mapper.dynamic => false
-
Index creation black/white list
action.auto_create_index => +aaa*,-bbb*,+ccc*,-*
- +: allowed
- -: disallowed
Versioning
- Optimistic concurrency control
Transactional read-then-update. It is recommended to set preference to _primary
curl -XPUT 'localhost:9200/twitter/tweet/1?version=2' -d '{
"message" : "elasticsearch now has versioning support, double cool!"
}'
NOTE: versioning is completely real time, and is not affected by the near real time aspects of search operations. If no version is provided, then the operation is executed without any version checks.
-
Version types
-
internal
only index the document if the given version is identical to the version of the stored document.
-
external or external_gt
only index the document if the given version is strictly higher than the version of the stored document or if there is no existing document. The given version will be used as the new version and will be stored with the new document. The supplied version must be a non-negative long number.
-
external_gte
only index the document if the given version is equal or higher than the version of the stored document. If there is no existing document the operation will succeed as well. The given version will be used as the new version and will be stored with the new document. The supplied version must be a non-negative long number.
-
force
correcting errors
-
Operation Type
-
op_type
$ curl -XPUT 'http://localhost:9200/twitter/tweet/1?op_type=create' -d '{ "user" : "kimchy", "post_date" : "2009-11-15T14:12:12", "message" : "trying out Elasticsearch" }'
-
create
$ curl -XPUT 'http://localhost:9200/twitter/tweet/1/_create' -d '{ "user" : "kimchy", "post_date" : "2009-11-15T14:12:12", "message" : "trying out Elasticsearch" }'
Automatic ID Generation
POST used instead of PUT (op_type will automatically be set to create)
$ curl -XPOST 'http://localhost:9200/twitter/tweet/' -d '{
"user" : "kimchy",
"post_date" : "2009-11-15T14:12:12",
"message" : "trying out Elasticsearch"
}'
automatic ID generation (6a8ca01c-7896-48e9-81cc-9f70661fcb32)
{
"_index" : "twitter",
"_type" : "tweet",
"_id" : "6a8ca01c-7896-48e9-81cc-9f70661fcb32",
"_version" : 1,
"created" : true
}
Routing
-
default
Hash of the document’s id value
-
explicit control
The value fed into the hash function used by the router can be directly specified on a per-operation basis using the routing parameter
$ curl -XPOST 'http://localhost:9200/twitter/tweet?routing=kimchy' -d '{ "user" : "kimchy", "post_date" : "2009-11-15T14:12:12", "message" : "trying out Elasticsearch" }'
When setting up explicit mapping, the _routing field can be optionally used to direct the index operation to extract the routing value from the document itself. This does come at the (very minimal) cost of an additional document parsing pass. If the _routing mapping is defined and set to be required, the index operation will fail if no routing value is provided or extracted.
Parents & Children
Child document index by parent(Automatically)
$ curl -XPUT localhost:9200/blogs/blog_tag/1122?parent=1111 -d '{
"tag" : "something"
}'
Timestamp (Deprecated in 2.0.0-beta2.)
Use Date
TTL (time to live) (Deprecated in 2.0.0-beta2.)
Future
Distributed
The index operation is directed to the primary shard based on its route (see the Routing section above) and performed on the actual node containing this shard. After the primary shard completes the operation, if needed, the update is distributed to applicable replicas.
Primary shard => Replicas
Write Consistency
-
Quorum
(>replicas/2+1) of active shards are available
-
action.write_consistency
- one
- quorum
- all
-
behavior
- node-by-node
- per-operation
-
sync replication
The index operation only returns after all active shards within the replication group have indexed the document
Refresh
- To refresh the shard (not the whole index)
- True - poor performance
- GetAPI - realtime (doesn't require refresh)
Noop Updates
-
detect_noop (version)
- true: compare document content
- false: ignore document content
-
no hard and fast rule
Timeout
-
default - 1 min
-
explicit
$ curl -XPUT 'http://localhost:9200/twitter/tweet/1?timeout=5m' -d '{ "user" : "kimchy", "post_date" : "2009-11-15T14:12:12", "message" : "trying out Elasticsearch" }'
Get API
Get:
curl -XGET 'http://localhost:9200/twitter/tweet/1'
Result:
{
"_index" : "twitter",
"_type" : "tweet",
"_id" : "1",
"_version" : 1,
"found": true,
"_source" : {
"user" : "kimchy",
"postDate" : "2009-11-15T14:12:12",
"message" : "trying out Elasticsearch"
}
}
Check Exists:
curl -XHEAD -i 'http://localhost:9200/twitter/tweet/1'
Result:
HTTP/1.1 404 Not Found
es.resource.type: index_expression
es.resource.id: twitter
es.index: twitter
Content-Type: text/plain; charset=UTF-8
Content-Length: 0
Realtime
-
To disable
action.get.realtime => false
-
fields (Good Practice)
- BECAUSE: At least for a period of time, basically, until the next flush
- THEREFORE: Assume fields will be loaded from source when using realtime GET
Optional Type
-
_type: optional
-
_all: fetch first cross types
Source filtering
-
Default: open
-
To disable
-
use fields
-
_source false
curl -XGET 'http://localhost:9200/twitter/tweet/1?_source=false'
-
-
Large document
- _source_include
- _source_exclude
-
Parameter
- list
- wildcards
-
Example
curl -XGET 'http://localhost:9200/twitter/tweet/1?_source_include=*.id&_source_exclude=entities'
-
Short notation(_source_include)
curl -XGET 'http://localhost:9200/twitter/tweet/1?_source=*.id,retweeted'
Fields
-
Example
curl -XGET 'http://localhost:9200/twitter/tweet/1?fields=title,content'
-
Backward compatibility
If the requested fields are not stored, they will be fetched from the _source
Be replaced by source filtering
-
Field values
-
Document (always array)
-
Meta (never array)
_routing
_parent
-
-
Leaf/Object
- Leaf success
- Object fail
Generated fields
-
No refresh occurred between indexing and refresh
GET will access the transaction log to fetch the document
-
Some fields are generated ONLY when indexing
-
default
error
-
ignore
ignore_errors_on_generated_fields=true
-
Getting the _source directly
-
Direct
curl -XGET 'http://localhost:9200/twitter/tweet/1/_source'
-
Source filtering
curl -XGET 'http://localhost:9200/twitter/tweet/1/_source?_source_include=*.id&_source_exclude=entities'
-
Existence
curl -XHEAD -i 'http://localhost:9200/twitter/tweet/1/_source'
Routing
Get:
curl -XGET 'http://localhost:9200/twitter/tweet/1?routing=kimchy'
Error:
{"error":{"root_cause":[
{"type":"index_not_found_exception",
"reason":"no such index",
"resource.type":"index_expression",
"resource.id":"twitter",
"index":"twitter"}],
"type":"index_not_found_exception",
"reason":"no such index",
"resource.type":"index_expression",
"resource.id":"twitter",
"index":"twitter"},"status":404}
Preference
Controls a preference of which shard replicas to execute the get request on
-
Default
Random
-
Preference
-
_primary
The operation will go and be executed only on the primary shards.
-
_local
The operation will prefer to be executed on a local allocated shard if possible.
-
-
Custom(string) value
A custom value will be used to guarantee that the same shards will be used for the same custom value. This can help with "jumping values" when hitting different shards in different refresh states. A sample value can be something like the web session id, or the user name.
Refresh
It may cause a heavy load on the system (and slows down indexing)
Distributed
-
The get operation gets hashed into a specific shard id.
-
It then gets redirected to one of the replicas within that shard id and returns the result.
The replicas are the primary shard and its replicas within that shard id group. This means that the more replicas we will have, the better GET scaling we will have.
Versioning support
Internally, Elasticsearch has marked the old document as deleted and added an entirely new document. The old version of the document doesn’t disappear immediately, although you won’t be able to access it. Elasticsearch cleans up deleted documents in the background as you continue to index more data.
Delete API
Delete:
$ curl -XDELETE 'http://localhost:9200/twitter/tweet/1'
Result:
{
"_shards" : {
"total" : 10,
"failed" : 0,
"successful" : 10
},
"found" : true,
"_index" : "twitter",
"_type" : "tweet",
"_id" : "1",
"_version" : 2
}
Versioning
Each document indexed is versioned. When deleting a document, the version can be specified to make sure the relevant document we are trying to delete is actually being deleted and it has not changed in the meantime. Every write operation executed on a document, deletes included, causes its version to be incremented.
Routing
$ curl -XDELETE 'http://localhost:9200/twitter/tweet/1?routing=kimchy'
Note, issuing a delete without the correct routing, will cause the document to not be deleted.
Many times, the routing value is not known when deleting a document. For those cases, when specifying the _routing mapping as required, and no routing value is specified, the delete will be broadcast automatically to all shards.
Parent
Note that deleting a parent document does not automatically delete its children.
-
delete all (parent_type#parent_id)
delete-by-query plugin
Automatic index creation
-
Automatically creates an index if it has not been created before
-
Automatically creates a dynamic type mapping for the specific type if it has not been created before
Distributed
Write Consistency
Refresh
Timeout
$ curl -XDELETE 'http://localhost:9200/twitter/tweet/1?timeout=5m'
Update API
curl -XPUT localhost:9200/test/type1/1 -d '{
"counter" : 1,
"tags" : ["red"]
}'
Scripted updates
-
Increment the counter
curl -XPOST 'localhost:9200/test/type1/1/_update' -d '{ "script" : { "inline": "ctx._source.counter += count", "params" : { "count" : 4 } } }'
-
Add a tag (no duplication check)
curl -XPOST 'localhost:9200/test/type1/1/_update' -d '{ "script" : { "inline": "ctx._source.tags += tag", "params" : { "tag" : "blue" } } }'
-
ctx map
- _source
- _index
- _type
- _id
- _version
- _routing
- _parent
- _timestamp
- _ttl
-
Add field
curl -XPOST 'localhost:9200/test/type1/1/_update' -d '{ "script" : "ctx._source.name_of_new_field = \"value_of_new_field\"" }'
-
Remove field
curl -XPOST 'localhost:9200/test/type1/1/_update' -d '{ "script" : "ctx._source.remove(\"name_of_field\")" }'
-
Condition
delete or noop
curl -XPOST 'localhost:9200/test/type1/1/_update' -d '{ "script" : { "inline": "ctx._source.tags.contains(tag) ? ctx.op = \"delete\" : ctx.op = \"none\"", "params" : { "tag" : "blue" } } }'
Updates with a partial document
-
Merge
Simple recursive merge, inner merging of objects, replacing core "keys/values" and arrays
curl -XPOST 'localhost:9200/test/type1/1/_update' -d '{ "doc" : { "name" : "new_name" } }'
script > doc
Detecting noop updates
curl -XPOST 'localhost:9200/test/type1/1/_update' -d '{
"doc" : {
"name" : "new_name"
},
"detect_noop": false
}'
Upserts
-
upsert
curl -XPOST 'localhost:9200/test/type1/1/_update' -d '{ "script" : { "inline": "ctx._source.counter += count", "params" : { "count" : 4 } }, "upsert" : { "counter" : 1 } }'
-
scripted_upsert
curl -XPOST 'localhost:9200/sessions/session/dh3sgudg8gsrgl/_update' -d '{ "scripted_upsert":true, "script" : { "id": "my_web_session_summariser", "params" : { "pageViewEvent" : { "url":"foo.com/bar", "response":404, "time":"2014-01-01 12:32" } } }, "upsert" : {} }'
-
doc_as_upsert
curl -XPOST 'localhost:9200/test/type1/1/_update' -d '{ "doc" : { "name" : "new_name" }, "doc_as_upsert" : true }'
Parameters
-
retry_on_conflict
In between the get and indexing phases of the update, it is possible that another process might have already updated the same document. By default, the update will fail with a version conflict exception. The retry_on_conflict parameter controls how many times to retry the update before finally throwing an exception.
-
routing
Routing is used to route the update request to the right shard and sets the routing for the upsert request if the document being updated doesn’t exist. Can’t be used to update the routing of an existing document.
-
parent
Parent is used to route the update request to the right shard and sets the parent for the upsert request if the document being updated doesn’t exist. Can’t be used to update the parent of an existing document.
-
timeout
Timeout waiting for a shard to become available.
-
consistency
The write consistency of the index/delete operation.
-
refresh
Refresh the relevant primary and replica shards (not the whole index) immediately after the operation occurs, so that the updated document appears in search results immediately.
-
fields
Return the relevant fields from the updated document. Specify _source to return the full updated source.
-
version & version_type
The update API uses the Elasticsearch’s versioning support internally to make sure the document doesn’t change during the update. You can use the version parameter to specify that the document should only be updated if it’s version matches the one specified. By setting version type to force you can force the new version of the document after update (use with care! with force there is no guarantee the document didn’t change).Version types external & external_gte are not supported.
Multi-document APIs
-
mget
curl 'localhost:9200/_mget' -d '{ "docs" : [ { "_index" : "test", "_type" : "type", "_id" : "1" }, { "_index" : "test", "_type" : "type", "_id" : "2" } ] }'
-
against index
curl 'localhost:9200/test/_mget' -d '{ "docs" : [ { "_type" : "type", "_id" : "1" }, { "_type" : "type", "_id" : "2" } ] }'
-
against type
curl 'localhost:9200/test/type/_mget' -d '{ "docs" : [ { "_id" : "1" }, { "_id" : "2" } ] }'
-
ids
curl 'localhost:9200/test/type/_mget' -d '{ "ids" : ["1", "2"] }'
Multi Get API
Optional Type
-
same document twice
curl 'localhost:9200/test/_mget' -d '{ "ids" : ["1", "1"] }'
-
explicit
GET /test/_mget/ { "docs" : [ { "_type":"typeA", "_id" : "1" }, { "_type":"typeB", "_id" : "1" } ] }
Source filtering
_source, _source_include & _source_exclude
curl 'localhost:9200/_mget' -d '{
"docs" : [
{
"_index" : "test",
"_type" : "type",
"_id" : "1",
"_source" : false
},
{
"_index" : "test",
"_type" : "type",
"_id" : "2",
"_source" : ["field3", "field4"]
},
{
"_index" : "test",
"_type" : "type",
"_id" : "3",
"_source" : {
"include": ["user"],
"exclude": ["user.location"]
}
}
]
}'
Fields
-
example
curl 'localhost:9200/_mget' -d '{ "docs" : [ { "_index" : "test", "_type" : "type", "_id" : "1", "fields" : ["field1", "field2"] }, { "_index" : "test", "_type" : "type", "_id" : "2", "fields" : ["field3", "field4"] } ] }'
-
specify default
curl 'localhost:9200/test/type/_mget?fields=field1,field2' -d '{ "docs" : [ { "_id" : "1" }, { "_id" : "2", "fields" : ["field3", "field4"] } ] }'
result:
"_id" : "1" => returns field1 and field2 "_id" : "2" => returns field3 and field4
Generated fields
Fields are generated only when indexing.
Routing
-
example
curl 'localhost:9200/_mget?routing=key1' -d '{ "docs" : [ { "_index" : "test", "_type" : "type", "_id" : "1", "_routing" : "key2" }, { "_index" : "test", "_type" : "type", "_id" : "2" } ] }'
result:
test/type/1 => key2 test/type/2 => key1
Security
URL-based access control
Bulk API
The bulk API makes it possible to perform many index/delete operations in a single API call
-
Increase the indexing speed
-
Client support for bulk requests
- Perl
- Python
-
Endpoint /_bulk
action_and_meta_data\n optional_source\n action_and_meta_data\n optional_source\n .... action_and_meta_data\n optional_source\n
-
Actions
index create delete update
-
Curl
-
text (--data-binary)
-
document (-d)
The latter doesn't preserve newlines
$ cat requests { "index" : { "_index" : "test", "_type" : "type1", "_id" : "1" } } { "field1" : "value1" } $ curl -s -XPOST localhost:9200/_bulk --data-binary "@requests"; echo {"took":7,"items":[{"create":{"_index":"test","_type":"type1","_id":"1","_version":1}}]}
-
-
Example
{ "index" : { "_index" : "test", "_type" : "type1", "_id" : "1" } } { "field1" : "value1" } { "delete" : { "_index" : "test", "_type" : "type1", "_id" : "2" } } { "create" : { "_index" : "test", "_type" : "type1", "_id" : "3" } } { "field1" : "value3" } { "update" : {"_id" : "1", "_type" : "type1", "_index" : "index1"} } { "doc" : {"field2" : "value2"} }
-
Above
-
merge
-
endpoints(use default unless explicit)
/_bulk
/{index}/_bulk
{index}/{type}/_bulk
-
only action_meta_data is parsed on the receiving node side (fast)
-
response - large JSON structure
-
number of actions - should be optimized per workload
-
HTTP API - no chunks (slow down)
-
Versioning
Routing
Parent
Timestamp
Deprecated in 2.0.0-beta2.
TTL
Deprecated in 2.0.0-beta2.
Write Consistency
Refresh
Update
-
Action inline _retry_on_conflict
-
Supports
- doc (partial document)
- upsert
- doc_as_upsert
- script
- params (for script)
- lang (for script)
- fields
-
Example
{ "update" : {"_id" : "1", "_type" : "type1", "_index" : "index1", "_retry_on_conflict" : 3} } { "doc" : {"field" : "value"} } { "update" : { "_id" : "0", "_type" : "type1", "_index" : "index1", "_retry_on_conflict" : 3} } { "script" : { "inline": "ctx._source.counter += param1", "lang" : "js", "params" : {"param1" : 1}}, "upsert" : {"counter" : 1}} { "update" : {"_id" : "2", "_type" : "type1", "_index" : "index1", "_retry_on_conflict" : 3} } { "doc" : {"field" : "value"}, "doc_as_upsert" : true } { "update" : {"_id" : "3", "_type" : "type1", "_index" : "index1", "fields" : ["_source"]} } { "doc" : {"field" : "value"} } { "update" : {"_id" : "4", "_type" : "type1", "_index" : "index1"} } { "doc" : {"field" : "value"}, "fields": ["_source"]}
Security
Term Vectors
https://www.elastic.co/guide/en/elasticsearch/reference/current/docs-termvectors.html
Multi termvectors API
https://www.elastic.co/guide/en/elasticsearch/reference/current/docs-multi-termvectors.html
Reference
https://www.elastic.co/guide/en/elasticsearch/reference/current/docs.html