Elasticsearch filter plugin

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Elasticsearch filter plugin

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  • Plugin version: v3.6.1
  • Released on: 2019-11-12
  • Changelog

For other versions, see the Versioned plugin docs.

Installation

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For plugins not bundled by default, it is easy to install by running bin/logstash-plugin install logstash-filter-elasticsearch. See Working with plugins for more details.

Getting Help

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For questions about the plugin, open a topic in the Discuss forums. For bugs or feature requests, open an issue in Github. For the list of Elastic supported plugins, please consult the Elastic Support Matrix.

Description

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Compatibility Note

Starting with Elasticsearch 5.3, there’s an HTTP setting called http.content_type.required. If this option is set to true, and you are using Logstash 2.4 through 5.2, you need to update the Elasticsearch filter plugin to version 3.1.1 or higher.

Search Elasticsearch for a previous log event and copy some fields from it into the current event. Below are two complete examples of how this filter might be used.

The first example uses the legacy query parameter where the user is limited to an Elasticsearch query_string. Whenever logstash receives an "end" event, it uses this elasticsearch filter to find the matching "start" event based on some operation identifier. Then it copies the @timestamp field from the "start" event into a new field on the "end" event. Finally, using a combination of the "date" filter and the "ruby" filter, we calculate the time duration in hours between the two events.

if [type] == "end" {
   elasticsearch {
      hosts => ["es-server"]
      query => "type:start AND operation:%{[opid]}"
      fields => { "@timestamp" => "started" }
   }

   date {
      match => ["[started]", "ISO8601"]
      target => "[started]"
   }

   ruby {
      code => "event.set('duration_hrs', (event.get('@timestamp') - event.get('started')) / 3600)"
   }
}

The example below reproduces the above example but utilises the query_template. This query_template represents a full Elasticsearch query DSL and supports the standard Logstash field substitution syntax. The example below issues the same query as the first example but uses the template shown.

if [type] == "end" {
      elasticsearch {
         hosts => ["es-server"]
         query_template => "template.json"
         fields => { "@timestamp" => "started" }
      }

      date {
         match => ["[started]", "ISO8601"]
         target => "[started]"
      }

      ruby {
         code => "event.set('duration_hrs', (event.get('@timestamp') - event.get('started')) / 3600)"
      }
}

template.json:

{
  "size": 1,
  "sort" : [ { "@timestamp" : "desc" } ],
  "query": {
    "query_string": {
      "query": "type:start AND operation:%{[opid]}"
    }
  },
  "_source": ["@timestamp"]
}

As illustrated above, through the use of opid, fields from the Logstash events can be referenced within the template. The template will be populated per event prior to being used to query Elasticsearch.

Notice also that when you use query_template, the Logstash attributes result_size and sort will be ignored. They should be specified directly in the JSON template, as shown in the example above.

Elasticsearch Filter Configuration Options

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This plugin supports the following configuration options plus the Common Options described later.

Also see Common Options for a list of options supported by all filter plugins.

 

aggregation_fields

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  • Value type is hash
  • Default value is {}

Hash of aggregation names to copy from elasticsearch response into Logstash event fields

Example:

    filter {
      elasticsearch {
        aggregation_fields => {
          "my_agg_name" => "my_ls_field"
        }
      }
    }

ca_file

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  • Value type is path
  • There is no default value for this setting.

SSL Certificate Authority file

docinfo_fields

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  • Value type is hash
  • Default value is {}

Hash of docinfo fields to copy from old event (found via elasticsearch) into new event

Example:

    filter {
      elasticsearch {
        docinfo_fields => {
          "_id" => "document_id"
          "_index" => "document_index"
        }
      }
    }

enable_sort

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  • Value type is boolean
  • Default value is true

Whether results should be sorted or not

fields

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  • Value type is array
  • Default value is {}

An array of fields to copy from the old event (found via elasticsearch) into the new event, currently being processed.

In the following example, the values of @timestamp and event_id on the event found via elasticsearch are copied to the current event’s started and start_id fields, respectively:

fields => {
  "@timestamp" => "started"
  "event_id" => "start_id"
}

hosts

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  • Value type is array
  • Default value is ["localhost:9200"]

List of elasticsearch hosts to use for querying.

index

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  • Value type is string
  • Default value is ""

Comma-delimited list of index names to search; use _all or empty string to perform the operation on all indices. Field substitution (e.g. index-name-%{date_field}) is available

password

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  • Value type is password
  • There is no default value for this setting.

Basic Auth - password

query

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  • Value type is string
  • There is no default value for this setting.

Elasticsearch query string. Read the Elasticsearch query string documentation. for more info at: https://www.elastic.co/guide/en/elasticsearch/reference/master/query-dsl-query-string-query.html#query-string-syntax

query_template

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  • Value type is string
  • There is no default value for this setting.

File path to elasticsearch query in DSL format. Read the Elasticsearch query documentation for more info at: https://www.elastic.co/guide/en/elasticsearch/reference/current/query-dsl.html

result_size

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  • Value type is number
  • Default value is 1

How many results to return

sort

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  • Value type is string
  • Default value is "@timestamp:desc"

Comma-delimited list of <field>:<direction> pairs that define the sort order

ssl

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  • Value type is boolean
  • Default value is false

SSL

tag_on_failure

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  • Value type is array
  • Default value is ["_elasticsearch_lookup_failure"]

Tags the event on failure to look up previous log event information. This can be used in later analysis.

user

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  • Value type is string
  • There is no default value for this setting.

Basic Auth - username

Common Options

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The following configuration options are supported by all filter plugins:

add_field

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  • Value type is hash
  • Default value is {}

If this filter is successful, add any arbitrary fields to this event. Field names can be dynamic and include parts of the event using the %{field}.

Example:

    filter {
      elasticsearch {
        add_field => { "foo_%{somefield}" => "Hello world, from %{host}" }
      }
    }
    # You can also add multiple fields at once:
    filter {
      elasticsearch {
        add_field => {
          "foo_%{somefield}" => "Hello world, from %{host}"
          "new_field" => "new_static_value"
        }
      }
    }

If the event has field "somefield" == "hello" this filter, on success, would add field foo_hello if it is present, with the value above and the %{host} piece replaced with that value from the event. The second example would also add a hardcoded field.

add_tag

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  • Value type is array
  • Default value is []

If this filter is successful, add arbitrary tags to the event. Tags can be dynamic and include parts of the event using the %{field} syntax.

Example:

    filter {
      elasticsearch {
        add_tag => [ "foo_%{somefield}" ]
      }
    }
    # You can also add multiple tags at once:
    filter {
      elasticsearch {
        add_tag => [ "foo_%{somefield}", "taggedy_tag"]
      }
    }

If the event has field "somefield" == "hello" this filter, on success, would add a tag foo_hello (and the second example would of course add a taggedy_tag tag).

enable_metric

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  • Value type is boolean
  • Default value is true

Disable or enable metric logging for this specific plugin instance. By default we record all the metrics we can, but you can disable metrics collection for a specific plugin.

  • Value type is string
  • There is no default value for this setting.

Add a unique ID to the plugin configuration. If no ID is specified, Logstash will generate one. It is strongly recommended to set this ID in your configuration. This is particularly useful when you have two or more plugins of the same type, for example, if you have 2 elasticsearch filters. Adding a named ID in this case will help in monitoring Logstash when using the monitoring APIs.

    filter {
      elasticsearch {
        id => "ABC"
      }
    }

periodic_flush

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  • Value type is boolean
  • Default value is false

Call the filter flush method at regular interval. Optional.

remove_field

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  • Value type is array
  • Default value is []

If this filter is successful, remove arbitrary fields from this event. Fields names can be dynamic and include parts of the event using the %{field} Example:

    filter {
      elasticsearch {
        remove_field => [ "foo_%{somefield}" ]
      }
    }
    # You can also remove multiple fields at once:
    filter {
      elasticsearch {
        remove_field => [ "foo_%{somefield}", "my_extraneous_field" ]
      }
    }

If the event has field "somefield" == "hello" this filter, on success, would remove the field with name foo_hello if it is present. The second example would remove an additional, non-dynamic field.

remove_tag

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  • Value type is array
  • Default value is []

If this filter is successful, remove arbitrary tags from the event. Tags can be dynamic and include parts of the event using the %{field} syntax.

Example:

    filter {
      elasticsearch {
        remove_tag => [ "foo_%{somefield}" ]
      }
    }
    # You can also remove multiple tags at once:
    filter {
      elasticsearch {
        remove_tag => [ "foo_%{somefield}", "sad_unwanted_tag"]
      }
    }

If the event has field "somefield" == "hello" this filter, on success, would remove the tag foo_hello if it is present. The second example would remove a sad, unwanted tag as well.