prune

Milestone: 1

This is a community-contributed plugin! It does not ship with logstash by default, but it is easy to install! To use this, you must have installed the contrib plugins package.

The prune filter is for pruning event data from @fileds based on whitelist/blacklist of field names or their values (names and values can also be regular expressions).

Synopsis

This is what it might look like in your config file:
filter {
  prune {
    add_field => ... # hash (optional), default: {}
    add_tag => ... # array (optional), default: []
    blacklist_names => ... # array (optional), default: ["%{[^}]+}"]
    blacklist_values => ... # hash (optional), default: {}
    interpolate => ... # boolean (optional), default: false
    remove_field => ... # array (optional), default: []
    remove_tag => ... # array (optional), default: []
    whitelist_names => ... # array (optional), default: []
    whitelist_values => ... # hash (optional), default: {}
  }
}

Details

add_field

  • 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 {
  prune {
    add_field => { "foo_%{somefield}" => "Hello world, from %{host}" }
  }
}

# You can also add multiple fields at once:

filter {
  prune {
    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

  • 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 {
  prune {
    add_tag => [ "foo_%{somefield}" ]
  }
}

# You can also add multiple tags at once:
filter {
  prune {
    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).

blacklist_names

  • Value type is array
  • Default value is ["%{[^}]+}"]

Exclude fields which names match specified regexps, by default exclude unresolved %{field} strings.

filter { 
  prune { 
    tags            => [ "apache-accesslog" ]
    blacklist_names => [ "method", "(referrer|status)", "${some}_field" ]
  }
}

blacklist_values

  • Value type is hash
  • Default value is {}

Exclude specified fields if their values match regexps. In case field values are arrays, the fields are pruned on per array item in case all array items are matched whole field will be deleted.

filter { 
  prune { 
    tags             => [ "apache-accesslog" ]
    blacklist_values => [ "uripath", "/index.php",
                          "method", "(HEAD|OPTIONS)",
                          "status", "^[^2]" ]
  }
}

exclude_tags DEPRECATED

  • DEPRECATED WARNING: This config item is deprecated. It may be removed in a further version.
  • Value type is array
  • Default value is []

Only handle events without all/any (controlled by exclude_any config option) of these tags. Optional.

interpolate

  • Value type is boolean
  • Default value is false

Trigger whether configation fields and values should be interpolated for dynamic values. Probably adds some performance overhead. Defaults to false.

remove_field

  • 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 {
  prune {
    remove_field => [ "foo_%{somefield}" ]
  }
}

# You can also remove multiple fields at once:

filter {
  prune {
    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

  • 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 {
  prune {
    remove_tag => [ "foo_%{somefield}" ]
  }
}

# You can also remove multiple tags at once:

filter {
  prune {
    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.

tags DEPRECATED

  • DEPRECATED WARNING: This config item is deprecated. It may be removed in a further version.
  • Value type is array
  • Default value is []

Only handle events with all/any (controlled by include_any config option) of these tags. Optional.

type DEPRECATED

  • DEPRECATED WARNING: This config item is deprecated. It may be removed in a further version.
  • Value type is string
  • Default value is ""

Note that all of the specified routing options (type,tags.exclude_tags,include_fields,exclude_fields) must be met in order for the event to be handled by the filter. The type to act on. If a type is given, then this filter will only act on messages with the same type. See any input plugin’s “type” attribute for more. Optional.

whitelist_names

  • Value type is array
  • Default value is []

Include only fields only if their names match specified regexps, default to empty list which means include everything.

filter { 
  prune { 
    tags            => [ "apache-accesslog" ]
    whitelist_names => [ "method", "(referrer|status)", "${some}_field" ]
  }
}

whitelist_values

  • Value type is hash
  • Default value is {}

Include specified fields only if their values match regexps. In case field values are arrays, the fields are pruned on per array item thus only matching array items will be included.

filter { 
  prune { 
    tags             => [ "apache-accesslog" ]
    whitelist_values => [ "uripath", "/index.php",
                          "method", "(GET|POST)",
                          "status", "^[^2]" ]
  }
}

This is documentation from lib/logstash/filters/prune.rb