[Filebeat] Improve ECS categorization in elasticsearch module (#16469)

- event.kind
- event.category
- event.type
- event.outcome
- lowercase http.request.method
- host.id
- host.name
- related.user

Closes #16160

CHANGELOG.next.asciidoc

@@ -177,6 +177,7 @@ https://github.com/elastic/beats/compare/v7.0.0-alpha2...master[Check the HEAD d
 - Update filebeat httpjson input to support pagination via Header and Okta module. {pull}16354[16354]
 - Improve ECS categorization field mapping in icinga module. {issue}16164[16164] {pull}16533[16533]
 - Improve ECS categorization field mappings in ibmmq module. {issue}16163[16163] {pull}16532[16532]
+- Improve ECS categorization, host field mappings in elasticsearch module. {issue}16160[16160] {pull}16469[16469]
 
 *Heartbeat*
 

filebeat/module/elasticsearch/audit/ingest/pipeline-json.yml

@@ -0,0 +1,124 @@
+description: Pipeline for parsing elasticsearch audit logs in JSON format
+processors:
+- json:
+    field: message
+    target_field: elasticsearch.audit
+- drop:
+    if: ctx.elasticsearch.audit?.type != null && ctx.elasticsearch.audit.type != 'audit'
+- remove:
+    field: elasticsearch.audit.type
+    ignore_missing: true
+- date:
+    if: ctx.elasticsearch.audit['@timestamp'] != null && ctx.event.timezone != null
+    field: elasticsearch.audit.@timestamp
+    target_field: elasticsearch.audit.@timestamp
+    formats:
+    - yyyy-MM-dd'T'HH:mm:ss,SSS
+    timezone: '{{ event.timezone }}'
+- remove:
+    if: ctx.elasticsearch.audit['@timestamp'] == null && ctx.event.timezone != null
+    field: event.timezone
+- rename:
+    field: elasticsearch.audit.timestamp
+    target_field: elasticsearch.audit.@timestamp
+    ignore_missing: true
+- dot_expander:
+    field: event.action
+    path: elasticsearch.audit
+- rename:
+    field: elasticsearch.audit.event.action
+    target_field: event.action
+    ignore_missing: true
+- dot_expander:
+    field: event.type
+    path: elasticsearch.audit
+- rename:
+    field: elasticsearch.audit.event.type
+    target_field: elasticsearch.audit.layer
+    ignore_missing: true
+- dot_expander:
+    field: origin.address
+    path: elasticsearch.audit
+- grok:
+    field: elasticsearch.audit.origin.address
+    patterns:
+    - \[%{IPORHOST:source.ip}\]:%{INT:source.port:int}
+    - '%{IPORHOST:source.ip}:%{INT:source.port:int}'
+    ignore_missing: true
+- rename:
+    field: elasticsearch.audit.origin.address
+    target_field: source.address
+    ignore_missing: true
+- dot_expander:
+    field: url.path
+    path: elasticsearch.audit
+- dot_expander:
+    field: url.query
+    path: elasticsearch.audit
+- set:
+    if: ctx.elasticsearch.audit?.url?.path != null && ctx.elasticsearch.audit?.url?.query
+      == null
+    field: url.original
+    value: '{{elasticsearch.audit.url.path}}'
+- set:
+    if: ctx.elasticsearch.audit?.url?.path != null && ctx.elasticsearch.audit?.url?.query
+      != null
+    field: url.original
+    value: '{{elasticsearch.audit.url.path}}?{{elasticsearch.audit.url.query}}'
+- remove:
+    if: ctx.elasticsearch.audit?.url?.path != null
+    field: elasticsearch.audit.url.path
+- remove:
+    if: ctx.elasticsearch.audit?.url?.query != null
+    field: elasticsearch.audit.url.query
+- dot_expander:
+    field: node.id
+    path: elasticsearch.audit
+- dot_expander:
+    field: node.name
+    path: elasticsearch.audit
+- rename:
+    field: elasticsearch.audit.node
+    target_field: elasticsearch.node
+- dot_expander:
+    field: user.name
+    path: elasticsearch.audit
+- rename:
+    field: elasticsearch.audit.user.name
+    target_field: user.name
+    ignore_missing: true
+- dot_expander:
+    field: request.method
+    path: elasticsearch.audit
+- rename:
+    field: elasticsearch.audit.request.method
+    target_field: http.request.method
+    ignore_missing: true
+- dot_expander:
+    field: request.body
+    path: elasticsearch.audit
+- rename:
+    field: elasticsearch.audit.request.body
+    target_field: http.request.body.content
+    ignore_missing: true
+- dot_expander:
+    field: cluster.name
+    path: elasticsearch.audit
+- rename:
+    field: elasticsearch.audit.cluster.name
+    target_field: elasticsearch.cluster.name
+    ignore_missing: true
+- rename:
+    field: elasticsearch.audit.level
+    target_field: log.level
+    ignore_missing: true
+- date:
+    field: elasticsearch.audit.@timestamp
+    target_field: '@timestamp'
+    formats:
+    - ISO8601
+    ignore_failure: true
+on_failure:
+- set:
+    field: error.message
+    value: '{{ _ingest.on_failure_message }}'