Translate filter plugin
editTranslate filter plugin
edit- Plugin version: v3.2.3
- Released on: 2018-09-05
- Changelog
For other versions, see the Versioned plugin docs.
Getting Help
editFor 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
editA 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. Each dictionary item is a key value pair.
You can specify dictionary entries in one of two ways:
-
The
dictionary
configuration item can contain a hash representing the mapping. -
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, for each event, the value from the field
setting is tested
against the dictionary and if it matches exactly (or matches a regex when
regex
configuration item has been enabled), the matched value is put in
the destination
field, but on no match the fallback
setting string is
used instead.
Example:
filter { translate { field => "[http_status]" destination => "[http_status_description]" dictionary => { "100" => "Continue" "101" => "Switching Protocols" "200" => "OK" "500" => "Server Error" } fallback => "I'm a teapot" } }
Occasionally, people find that they have a field with a variable sized array of
values or objects that need some enrichment. The iterate_on
setting helps in
these cases.
Alternatively, for simple string search and replacements for just a few values you might consider using the gsub function of the mutate filter.
It is possible to provide multi-valued dictionary values. When using a YAML or
JSON dictionary, you can have the value as a hash (map) or an array datatype.
When using a CSV dictionary, multiple values in the translation must be
extracted with another filter e.g. Dissect or KV.
Note that the fallback
is a string so on no match the fallback setting needs
to formatted so that a filter can extract the multiple values to the correct fields.
File based dictionaries are loaded in a separate thread using a scheduler.
If you set a refresh_interval
of 300 seconds (5 minutes) or less then the
modified time of the file is checked before reloading. Very large dictionaries
are supported, internally tested at 100 000 key/values, and we minimise
the impact on throughput by having the refresh in the scheduler thread.
Any ongoing modification of the dictionary file should be done using a
copy/edit/rename or create/rename mechanism to avoid the refresh code from
processing half-baked dictionary content.
Translate Filter Configuration Options
editThis plugin supports the following configuration options plus the Common Options described later.
Setting | Input type | Required |
---|---|---|
No |
||
No |
||
a valid filesystem path |
No |
|
No |
||
No |
||
Yes |
||
No |
||
No |
||
No |
||
No |
||
No |
Also see Common Options for a list of options supported by all filter plugins.
destination
edit- 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
edit- 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
edit- 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.
Specify any integer-based keys in quotes. The
value taken from the event’s field
setting is converted to a string. The
lookup dictionary keys must also be strings, and the quotes make the
integer-based keys function as a string. 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 CSV format expects exactly two columns, with the first serving
as the original text (lookup key), and the second column as the translation.
exact
edit- 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
edit- 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
edit- 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.
iterate_on
edit- Value type is string
- There is no default value for this setting.
When the value that you need to perform enrichment on is a variable sized array
then specify the field name in this setting. This setting introduces two modes,
1) when the value is an array of strings and 2) when the value is an array of
objects (as in JSON object).
In the first mode, you should have the same field name in both field
and
iterate_on
, the result will be an array added to the field specified in the
destination
setting. This array will have the looked up value (or the
fallback
value or nil) in same ordinal position as each sought value.
In the second mode, specify the field that has the array of objects in
iterate_on
then specify the field in each object that provides the sought value
with field
and the field to write the looked up value (or the fallback
value)
to with destination
.
For a dictionary of:
100,Yuki 101,Rupert 102,Ahmed 103,Kwame
Example of Mode 1
filter { translate { iterate_on => "[collaborator_ids]" field => "[collaborator_ids]" destination => "[collaborator_names]" fallback => "Unknown" } }
Before
{ "collaborator_ids": [100,103,110,102] }
After
{ "collaborator_ids": [100,103,110,102], "collabrator_names": ["Yuki","Kwame","Unknown","Ahmed"] }
Example of Mode 2
filter { translate { iterate_on => "[collaborators]" field => "[id]" destination => "[name]" fallback => "Unknown" } }
Before
{ "collaborators": [ { "id": 100 }, { "id": 103 }, { "id": 110 }, { "id": 101 } ] }
After
{ "collaborators": [ { "id": 100, "name": "Yuki" }, { "id": 103, "name": "Kwame" }, { "id": 110, "name": "Unknown" }, { "id": 101, "name": "Rupert" } ] }
override
edit- 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
edit- 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.
A value of zero or less will disable refresh.
regex
edit- Value type is boolean
-
Default value is
false
To treat dictionary keys as regular expressions, set regex => true
.
Be sure to escape dictionary key strings for use with regex. Resources on regex formatting are available online.
refresh_behaviour
edit- Value type is string
-
Default value is
merge
When using a dictionary file, this setting indicates how the update will be executed.
Setting this to merge
causes the new dictionary to be merged into the old one. This means
same entry will be updated but entries that existed before but not in the new dictionary
will remain after the merge; replace
causes the whole dictionary to be replaced
with a new one (deleting all entries of the old one on update).
Common Options
editThe following configuration options are supported by all filter plugins:
Setting | Input type | Required |
---|---|---|
No |
||
No |
||
No |
||
No |
||
No |
||
No |
||
No |
add_field
edit- 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 { 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.
add_tag
edit- 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 { 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).
enable_metric
edit- 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.
id
edit- 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 translate filters.
Adding a named ID in this case will help in monitoring Logstash when using the monitoring APIs.
filter { translate { id => "ABC" } }
periodic_flush
edit- Value type is boolean
-
Default value is
false
Call the filter flush method at regular interval. Optional.
remove_field
edit- 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 { 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.
remove_tag
edit- 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 { 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.