For other versions, see theVersioned plugin docs.
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.
The mutate filter allows you to perform general mutations on fields. Youcan rename, remove, replace, and modify fields in your events.
Mutations in a config file are executed in this order:
You can control the order by using separate mutate blocks.
Example:
filter { mutate { split => ["hostname", "."] add_field => { "shortHostname" => "%{hostname[0]}" } } mutate { rename => ["shortHostname", "hostname" ] }}
This plugin supports the following configuration options plus the Common Options described later.
Setting | Input type | Required |
---|---|---|
No |
||
No |
||
No |
||
No |
||
No |
||
No |
||
No |
||
No |
||
No |
||
No |
||
No |
||
No |
||
No |
||
No |
Also see Common Options for a list of options supported by allfilter plugins.
Convert a field’s value to a different type, like turning a string to aninteger. If the field value is an array, all members will be converted.If the field is a hash no action will be taken.
Valid conversion targets, and their expected behaviour with different inputs are:
integer
:
"1,000"
produces an integer with value of one thousand); when strings have decimal parts, they are truncated.3.99
becomes 3
, -2.7
becomes -2
)1
and 0
respectivelyinteger_eu
:
integer
, except string values support dot-separators and comma-decimals (e.g., "1.000"
produces an integer with value of one thousand)float
:
"1,000.5"
produces an integer with value of one thousand and one half)1.0
and 0.0
respectivelyfloat_eu
:
float
, except string values support dot-separators and comma-decimals (e.g., "1.000,5"
produces an integer with value of one thousand and one half)string
:
boolean
:
false
true
false
true
"true"
, "t"
, "yes"
, "y"
, "1"`and `"1.0"
are converted to boolean true
"false"
, "f"
, "no"
, "n"
, "0"
and "0.0"
are converted to boolean false
false
This plugin can convert multiple fields in the same document, see the example below.
Example:
filter { mutate { convert => { "fieldname" => "integer" "booleanfield" => "boolean" } }}
Copy an existing field to another field. Existing target field will be overriden.
Example:
filter { mutate { copy => { "source_field" => "dest_field" } }}
Match a regular expression against a field value and replace all matcheswith a replacement string. Only fields that are strings or arrays ofstrings are supported. For other kinds of fields no action will be taken.
This configuration takes an array consisting of 3 elements perfield/substitution.
Be aware of escaping any backslash in the config file.
Example:
filter { mutate { gsub => [ # replace all forward slashes with underscore "fieldname", "/", "_", # replace backslashes, question marks, hashes, and minuses # with a dot "." "fieldname2", "[\\?#-]", "." ] }}
Join an array with a separator character. Does nothing on non-array fields.
Example:
filter { mutate { join => { "fieldname" => "," } }}
Convert a string to its lowercase equivalent.
Example:
filter { mutate { lowercase => [ "fieldname" ] }}
Merge two fields of arrays or hashes.String fields will be automatically be converted into an array, so:
`array` + `string` will work`string` + `string` will result in an 2 entry array in `dest_field``array` and `hash` will not work
Example:
filter { mutate { merge => { "dest_field" => "added_field" } }}
Set the default value of a field that exists but is null
Example:
filter { mutate { # Sets the default value of the 'field1' field to 'default_value' coerce => { "field1" => "default_value" } }}
Rename one or more fields.
Example:
filter { mutate { # Renames the 'HOSTORIP' field to 'client_ip' rename => { "HOSTORIP" => "client_ip" } }}
Replace the value of a field with a new value. The new value can include %{foo}
stringsto help you build a new value from other parts of the event.
Example:
filter { mutate { replace => { "message" => "%{source_host}: My new message" } }}
Split a field to an array using a separator character. Only works on stringfields.
Example:
filter { mutate { split => { "fieldname" => "," } }}
Strip whitespace from field. NOTE: this only works on leading and trailing whitespace.
Example:
filter { mutate { strip => ["field1", "field2"] }}
Update an existing field with a new value. If the field does not exist,then no action will be taken.
Example:
filter { mutate { update => { "sample" => "My new message" } }}
Convert a string to its uppercase equivalent.
Example:
filter { mutate { uppercase => [ "fieldname" ] }}
Convert a string to its capitalized equivalent.
Example:
filter { mutate { capitalize => [ "fieldname" ] }}
The following configuration options are supported by all filter plugins:
Setting | Input type | Required |
---|---|---|
No |
||
No |
||
No |
||
No |
||
No |
||
No |
||
No |
{}
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 { mutate { add_field => { "foo_%{somefield}" => "Hello world, from %{host}" } }}
# You can also add multiple fields at once:filter { mutate { 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 thevalue above and the %{host}
piece replaced with that value from theevent. 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 { mutate { add_tag => [ "foo_%{somefield}" ] }}
# You can also add multiple tags at once:filter { mutate { 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).
true
Disable or enable metric logging for this specific plugin instanceby default we record all the metrics we can, but you can disable metrics collectionfor a specific plugin.
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 usefulwhen you have two or more plugins of the same type, for example, if you have 2 mutate filters.Adding a named ID in this case will help in monitoring Logstash when using the monitoring APIs.
filter { mutate { id => "ABC" }}
false
Call the filter flush method at regular interval.Optional.
[]
If this filter is successful, remove arbitrary fields from this event.Example:
filter { mutate { remove_field => [ "foo_%{somefield}" ] }}
# You can also remove multiple fields at once:filter { mutate { 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 secondexample 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 { mutate { remove_tag => [ "foo_%{somefield}" ] }}
# You can also remove multiple tags at once:filter { mutate { 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 examplewould remove a sad, unwanted tag as well.