Translate filter plugin

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  • Plugin version: v3.0.2
  • Released on: 2017-06-23
  • Changelog

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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A general search and replace tool that uses a configured hash and/or a file to determine replacement values. Currently supported are YAML, JSON, and CSV files.

The dictionary entries can be specified in one of two ways: First, the dictionary configuration item may contain a hash representing the mapping. Second, an external file (readable by logstash) may be specified in the dictionary_path configuration item. These two methods may not be used in conjunction; it will produce an error.

Operationally, if the event field specified in the field configuration matches the EXACT contents of a dictionary entry key (or matches a regex if regex configuration item has been enabled), the field’s value will be substituted with the matched key’s value from the dictionary.

By default, the translate filter will replace the contents of the maching event field (in-place). However, by using the destination configuration item, you may also specify a target event field to populate with the new translated value.

Alternatively, for simple string search and replacements for just a few values you might consider using the gsub function of the mutate filter.

Translate Filter Configuration Options

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

Setting Input type Required

destination

string

No

dictionary

hash

No

dictionary_path

a valid filesystem path

No

exact

boolean

No

fallback

string

No

field

string

Yes

override

boolean

No

refresh_interval

number

No

regex

boolean

No

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

 

destination

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  • Value type is string
  • Default value is "translation"

The destination field you wish to populate with the translated code. The default is a field named translation. Set this to the same value as source if you want to do a substitution, in this case filter will allways succeed. This will clobber the old value of the source field!

dictionary

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  • Value type is hash
  • Default value is {}

The dictionary to use for translation, when specified in the logstash filter configuration item (i.e. do not use the @dictionary_path file).

Example:

    filter {
      translate {
        dictionary => [ "100", "Continue",
                        "101", "Switching Protocols",
                        "merci", "thank you",
                        "old version", "new version" ]
      }
    }

It is an error to specify both dictionary and dictionary_path.

dictionary_path

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

The full path of the external dictionary file. The format of the table should be a standard YAML, JSON, or CSV. Make sure you specify any integer-based keys in quotes. For example, the YAML file should look something like this:

    "100": Continue
    "101": Switching Protocols
    merci: gracias
    old version: new version

it is an error to specify both dictionary and dictionary_path.

The currently supported formats are YAML, JSON, and CSV. Format selection is based on the file extension: json for JSON, yaml or yml for YAML, and csv for CSV. The JSON format only supports simple key/value, unnested objects. The CSV format expects exactly two columns, with the first serving as the original text, and the second column as the replacement.

exact

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  • Value type is boolean
  • Default value is true

When exact => true, the translate filter will populate the destination field with the exact contents of the dictionary value. When exact => false, the filter will populate the destination field with the result of any existing destination field’s data, with the translated value substituted in-place.

For example, consider this simple translation.yml, configured to check the data field:

    foo: bar

If logstash receives an event with the data field set to foo, and exact => true, the destination field will be populated with the string bar. If exact => false, and logstash receives the same event, the destination field will be also set to bar. However, if logstash receives an event with the data field set to foofing, the destination field will be set to barfing.

Set both exact => true AND regex => `true if you would like to match using dictionary keys as regular expressions. A large dictionary could be expensive to match in this case.

fallback

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

In case no translation occurs in the event (no matches), this will add a default translation string, which will always populate field, if the match failed.

For example, if we have configured fallback => "no match", using this dictionary:

    foo: bar

Then, if logstash received an event with the field foo set to bar, the destination field would be set to bar. However, if logstash received an event with foo set to nope, then the destination field would still be populated, but with the value of no match. This configuration can be dynamic and include parts of the event using the %{field} syntax.

field

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

The name of the logstash event field containing the value to be compared for a match by the translate filter (e.g. message, host, response_code).

If this field is an array, only the first value will be used.

override

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  • Value type is boolean
  • Default value is false

If the destination (or target) field already exists, this configuration item specifies whether the filter should skip translation (default) or overwrite the target field value with the new translation value.

refresh_interval

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  • Value type is number
  • Default value is 300

When using a dictionary file, this setting will indicate how frequently (in seconds) logstash will check the dictionary file for updates.

regex

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  • Value type is boolean
  • Default value is false

If you’d like to treat dictionary keys as regular expressions, set exact => true. Note: this is activated only when exact => true.

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 {
  PLUGIN_NAME {
    add_field => { "foo_%{somefield}" => "Hello world, from %{host}" }
  }
}
# You can also add multiple fields at once:
filter {
  PLUGIN_NAME {
    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 {
  PLUGIN_NAME {
    add_tag => [ "foo_%{somefield}" ]
  }
}
# You can also add multiple tags at once:
filter {
  PLUGIN_NAME {
    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 instance, this ID is used for tracking information for a specific configuration of the plugin.

output {
 stdout {
   id => "ABC"
 }
}

If you don’t explicitely set this variable Logstash will generate a unique name.

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 {
  PLUGIN_NAME {
    remove_field => [ "foo_%{somefield}" ]
  }
}
# You can also remove multiple fields at once:
filter {
  PLUGIN_NAME {
    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 {
  PLUGIN_NAME {
    remove_tag => [ "foo_%{somefield}" ]
  }
}
# You can also remove multiple tags at once:
filter {
  PLUGIN_NAME {
    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.