A general search and replace tool which uses a configured hash and/or a YAML file to determine replacement values.
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 YAML 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.
filter {
translate {
add_field => ... # hash (optional), default: {}
add_tag => ... # array (optional), default: []
destination => ... # string (optional), default: "translation"
dictionary => ... # hash (optional), default: {}
dictionary_path => ... # a valid filesystem path (optional)
exact => ... # boolean (optional), default: true
fallback => ... # string (optional)
field => ... # string (required)
override => ... # boolean (optional), default: false
refresh_interval => ... # number (optional), default: 300
regex => ... # boolean (optional), default: false
remove_field => ... # array (optional), default: []
remove_tag => ... # array (optional), default: []
}
}
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 {
translate {
add_field => { "foo_%{somefield}" => "Hello world, from %{host}" }
}
}
# You can also add multiple fields at once:
filter {
translate {
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.
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 {
translate {
add_tag => [ "foo_%{somefield}" ]
}
}
# You can also add multiple tags at once:
filter {
translate {
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).
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!
The dictionary to use for translation, when specified in the logstash filter configuration item (i.e. do not use the @dictionary_path YAML file) Example:
filter {
translate {
dictionary => [ "100", "Continue",
"101", "Switching Protocols",
"merci", "thank you",
"old version", "new version" ]
}
} NOTE: it is an error to specify both dictionary and dictionary_path
The full path of the external YAML dictionary file. The format of the table should be a standard YAML file. Make sure you specify any integer-based keys in quotes. The YAML file should look something like this:
"100": Continue
"101": Switching Protocols
merci: gracias
old version: new version
NOTE: it is an error to specify both dictionary and dictionary_path
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.
Only handle events without all/any (controlled by exclude_any config option) of these tags. Optional.
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”.
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.
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.
When using a dictionary file, this setting will indicate how frequently (in seconds) logstash will check the YAML file for updates.
If you’d like to treat dictionary keys as regular expressions, set exact => true.
Note: this is activated only when exact => true.
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 {
translate {
remove_field => [ "foo_%{somefield}" ]
}
}
# You can also remove multiple fields at once:
filter {
translate {
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.
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 {
translate {
remove_tag => [ "foo_%{somefield}" ]
}
}
# You can also remove multiple tags at once:
filter {
translate {
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.
Only handle events with all/any (controlled by include_any config option) of these tags. Optional.
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.