• Plugin version: v3.3.5 (Other versions)
• Released on: 2023-09-19
• Changelog

For questions about the plugin, open a topic in theDiscuss forums. For bugs or feature requests, open an issue inGithub. For the list of Elastic supported plugins, please consult theElastic Support Matrix.

Parse user agent strings into structured data based on BrowserScope data

UserAgent filter, adds information about user agent like name, version, operating system, and device.

The plugin ships with theregexes.yaml database made available from ua-parser with an Apache 2.0 license. For more details on ua-parser, seehttps://github.com/ua-parser/uap-core/.

This plugin can be used to parse user-agent (UA)into fields compliant with the Elastic Common Schema. Here’s howECS compatibility mode affects output.

[version] and[os_version] fields were added in Logstash7.14 and are not available by default in earlier versions.

Example:

filter {  useragent {    source => 'message'  }}

Given an event with themessage field set as:Mozilla/5.0 (Macintosh; Intel Mac OS X 10.11; rv:45.0) Gecko/20100101 Firefox/45.0 produces the following fields:

{    "name"=>"Firefox",    "version"=>"45.0",    "major"=>"45",    "minor"=>"0",    "os_name"=>"Mac OS X",    "os_version"=>"10.11",    "os_full"=>"Mac OS X 10.11",    "os_major"=>"10",    "os_minor"=>"11",    "device"=>"Mac"}

1. since plugin version 3.3.0
2. since plugin version 3.3.0

and with ECS enabled:

{    "user_agent"=>{        "name"=>"Firefox",        "version"=>"45.0",        "os"=>{            "name"=>"Mac OS X",            "version"=>"10.11",            "full"=>"Mac OS X 10.11"        },        "device"=>{"name"=>"Mac"},    }}

This plugin supports the following configuration options plus theCommon options described later.

Also seeCommon options for a list of options supported by all filter plugins.

• Value type isstring

• Supported values are:

  • disabled: does not use ECS-compatible field names (fields might be set at the root of the event)
  • v1,v8: uses fields that are compatible with Elastic Common Schema (for example,[user_agent][version])

• Default value depends on which version of Logstash is running:

  • When Logstash provides apipeline.ecs_compatibility setting, its value is used as the default
  • Otherwise, the default value isdisabled.

Controls this plugin’s compatibility with theElastic Common Schema (ECS). The value of this setting affects thedefault value oftarget.

• Value type isnumber
• Default value is100000

UA parsing is surprisingly expensive. This filter uses an LRU cache to take advantage of the fact that user agents are often found adjacent to one another in log files and rarely have a random distribution. The higher you set this the more likely an item is to be in the cache and the faster this filter will run. However, if you set this too high you can use more memory than desired.

Experiment with different values for this option to find the best performance for your dataset.

This MUST be set to a value > 0. There is really no reason to not want this behavior, the overhead is minimal and the speed gains are large.

It is important to note that this config value is global. That is to say all instances of the user agent filter share the same cache. The last declared cache size willwin. The reason for this is that there would be no benefit to having multiple caches for different instances at different points in the pipeline, that would just increase the number of cache misses and waste memory.

• Value type isstring
• Default value is""

A string to prepend to all of the extracted keys

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

If not specified, this will default to theregexes.yaml that ships with logstash. Otherwise use the providedregexes.yaml file.

You can find the latest version of this here:https://github.com/ua-parser/uap-core/blob/master/regexes.yaml

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

The field containing the user agent string. If this field is an array, only the first value will be used.

• Value type isstring

• Default value depends on whetherecs_compatibility is enabled:

  • ECS Compatibility disabled: no default value for this setting
  • ECS Compatibility enabled:"user_agent"

The name of the field to assign user agent data into.

If not specified user agent data will be stored in the root of the event.

These configuration options are supported by all filter plugins:

• Value type ishash
• 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 {  useragent {    add_field => { "foo_%{somefield}" => "Hello world, from %{host}" }  }}

# You can also add multiple fields at once:filter {  useragent {    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 fieldfoo_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.

• Value type isarray
• 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 {  useragent {    add_tag => [ "foo_%{somefield}" ]  }}

# You can also add multiple tags at once:filter {  useragent {    add_tag => [ "foo_%{somefield}", "taggedy_tag"]  }}

If the event has field"somefield" == "hello" this filter, on success, would add a tagfoo_hello (and the second example would of course add ataggedy_tag tag).

• Value type isboolean
• Default value istrue

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 isstring
• There is no default value for this setting.

Add a uniqueID 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 useragent filters. Adding a named ID in this case will help in monitoring Logstash when using the monitoring APIs.

filter {  useragent {    id => "ABC"  }}

• Value type isboolean
• Default value isfalse

Call the filter flush method at regular interval. Optional.

• Value type isarray
• 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 {  useragent {    remove_field => [ "foo_%{somefield}" ]  }}

# You can also remove multiple fields at once:filter {  useragent {    remove_field => [ "foo_%{somefield}", "my_extraneous_field" ]  }}

If the event has field"somefield" == "hello" this filter, on success, would remove the field with namefoo_hello if it is present. The second example would remove an additional, non-dynamic field.

• Value type isarray
• 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 {  useragent {    remove_tag => [ "foo_%{somefield}" ]  }}

# You can also remove multiple tags at once:filter {  useragent {    remove_tag => [ "foo_%{somefield}", "sad_unwanted_tag"]  }}

If the event has field"somefield" == "hello" this filter, on success, would remove the tagfoo_hello if it is present. The second example would remove a sad, unwanted tag as well.