ConsumeElasticsearch

Description:

A processor that repeatedly runs a paginated query against a field using a Range query to consume new Documents from an Elasticsearch index/query. The processor will retrieve multiple pages of results until either no more results are available or the Pagination Keep Alive expiration is reached, after which the Range query will automatically update the field constraint based on the last retrieved Document value.

Additional Details...

Tags:

elasticsearch, elasticsearch5, elasticsearch6, elasticsearch7, elasticsearch8, query, scroll, page, search, json

Properties:

In the list below, the names of required properties appear in bold. Any other properties (not in bold) are considered optional. The table also indicates any default values, and whether a property supports the NiFi Expression Language.

Display Name	API Name	Default Value	Allowable Values	Description
Range Query Field	es-rest-range-field			Field to be tracked as part of an Elasticsearch Range query using a "gt" bound match. This field must exist within the Elasticsearch document for it to be retrieved.
Sort Order	es-rest-sort-order	asc	asc desc	The order in which to sort the "Range Query Field". A "sort" clause for the "Range Query Field" field will be prepended to any provided "Sort" clauses. If a "sort" clause already exists for the "Range Query Field" field, it will not be updated.
Initial Value	es-rest-range-initial-value			The initial value to use for the query if the processor has not run previously. If the processor has run previously and stored a value in its state, this property will be ignored. If no value is provided, and the processor has not previously run, no Range query bounds will be used, i.e. all documents will be retrieved in the specified "Sort Order".
Initial Value Date Format	es-rest-range-format			If the "Range Query Field" is a Date field, convert the "Initial Value" to a date with this format. If not specified, Elasticsearch will use the date format provided by the "Range Query Field"'s mapping. For valid syntax, see https://www.elastic.co/guide/en/elasticsearch/reference/current/mapping-date-format.html This Property is only considered if the [Initial Value] Property has a value specified.
Initial Value Date Time Zone	es-rest-range-time-zone			If the "Range Query Field" is a Date field, convert the "Initial Value" to UTC with this time zone. Valid values are ISO 8601 UTC offsets, such as "+01:00" or "-08:00", and IANA time zone IDs, such as "Europe/London". This Property is only considered if the [Initial Value] Property has a value specified.
Additional Filters	es-rest-additional-filters			One or more query filters in JSON syntax, not Lucene syntax. Ex: [{"match":{"somefield":"somevalue"}}, {"match":{"anotherfield":"anothervalue"}}]. These filters wil be used as part of a Bool query's filter.
Size	es-rest-size			The maximum number of documents to retrieve in the query. If the query is paginated, this "size" applies to each page of the query, not the "size" of the entire result set. Supports Expression Language: true (will be evaluated using variable registry only)
Sort	es-rest-query-sort			Sort results by one or more fields, in JSON syntax. Ex: [{"price" : {"order" : "asc", "mode" : "avg"}}, {"post_date" : {"format": "strict_date_optional_time_nanos"}}] Supports Expression Language: true (will be evaluated using variable registry only)
Aggregations	es-rest-query-aggs			One or more query aggregations (or "aggs"), in JSON syntax. Ex: {"items": {"terms": {"field": "product", "size": 10}}} Supports Expression Language: true (will be evaluated using variable registry only)
Fields	es-rest-query-fields			Fields of indexed documents to be retrieved, in JSON syntax. Ex: ["user.id", "http.response.", {"field": "@timestamp", "format": "epoch_millis"}] Supports Expression Language: true (will be evaluated using variable registry only)*
Script Fields	es-rest-query-script-fields			Fields to created using script evaluation at query runtime, in JSON syntax. Ex: {"test1": {"script": {"lang": "painless", "source": "doc['price'].value * 2"}}, "test2": {"script": {"lang": "painless", "source": "doc['price'].value * params.factor", "params": {"factor": 2.0}}}} Supports Expression Language: true (will be evaluated using variable registry only)
Query Attribute	el-query-attribute			If set, the executed query will be set on each result flowfile in the specified attribute. Supports Expression Language: true (will be evaluated using variable registry only)
Index	el-rest-fetch-index			The name of the index to use. Supports Expression Language: true (will be evaluated using variable registry only)
Type	el-rest-type			The type of this document (used by Elasticsearch for indexing and searching). Supports Expression Language: true (will be evaluated using variable registry only)
Client Service	el-rest-client-service		Controller Service API: ElasticSearchClientService Implementation: ElasticSearchClientServiceImpl	An Elasticsearch client service to use for running queries.
Search Results Split	el-rest-split-up-hits	PER_RESPONSE	PER_HIT PER_RESPONSE PER_QUERY	Output a flowfile containing all hits or one flowfile for each individual hit or one flowfile containing all hits from all paged responses.
Search Results Format	el-rest-format-hits	FULL	FULL SOURCE_ONLY METADATA_ONLY	Format of Hits output.
Aggregation Results Split	el-rest-split-up-aggregations	PER_RESPONSE	PER_HIT PER_RESPONSE	Output a flowfile containing all aggregations or one flowfile for each individual aggregation.
Aggregation Results Format	el-rest-format-aggregations	FULL	FULL BUCKETS_ONLY METADATA_ONLY	Format of Aggregation output.
Output No Hits	el-rest-output-no-hits	false	true false	Output a "hits" flowfile even if no hits found for query. If true, an empty "hits" flowfile will be output even if "aggregations" are output.
Pagination Type	el-rest-pagination-type	SCROLL	SCROLL SEARCH_AFTER POINT_IN_TIME	Pagination method to use. Not all types are available for all Elasticsearch versions, check the Elasticsearch docs to confirm which are applicable and recommended for your service.
Pagination Keep Alive	el-rest-pagination-keep-alive	10 mins		Pagination "keep_alive" period. Period Elasticsearch will keep the scroll/pit cursor alive in between requests (this is not the time expected for all pages to be returned, but the maximum allowed time for requests between page retrievals).

Dynamic Properties:

Supports Sensitive Dynamic Properties: No

Dynamic Properties allow the user to specify both the name and value of a property.

Name	Value	Description
The name of a URL query parameter to add	The value of the URL query parameter	Adds the specified property name/value as a query parameter in the Elasticsearch URL used for processing. These parameters will override any matching parameters in the query request body. For SCROLL type queries, these parameters are only used in the initial (first page) query as the Elasticsearch Scroll API does not support the same query parameters for subsequent pages of data. Supports Expression Language: true (will be evaluated using variable registry only)

Relationships:

Name	Description
aggregations	Aggregations are routed to this relationship.
hits	Search hits are routed to this relationship.

Reads Attributes:

None specified.

Writes Attributes:

Name	Description
mime.type	application/json
page.number	The number of the page (request), starting from 1, in which the results were returned that are in the output flowfile
hit.count	The number of hits that are in the output flowfile
elasticsearch.query.error	The error message provided by Elasticsearch if there is an error querying the index.

State management:

Scope	Description
CLUSTER	The pagination state (scrollId, searchAfter, pitId, hitCount, pageCount, pageExpirationTimestamp, trackingRangeValue) is retained in between invocations of this processor until the Scroll/PiT has expired (when the current time is later than the last query execution plus the Pagination Keep Alive interval).

Restricted:

This component is not restricted.

Input requirement:

This component does not allow an incoming relationship.

System Resource Considerations:

Resource	Description
MEMORY	Care should be taken on the size of each page because each response from Elasticsearch will be loaded into memory all at once and converted into the resulting flowfiles.