File output plugin

• Plugin version: v4.3.0
• Released on: 2020-04-27
• Changelog

For other versions, see the Versioned 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.

This output writes events to files on disk. You can use fields from the event as parts of the filename and/or path.

By default, this output writes one event per line in json format. You can customise the line format using the line codec like

output {
 file {
   path => ...
   codec => line { format => "custom format: %{message}"}
 }
}

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

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

• Value type is boolean
• Default value is true

If the configured file is deleted, but an event is handled by the plugin, the plugin will recreate the file. Default ⇒ true

• Value type is number
• Default value is -1

Dir access mode to use. Note that due to the bug in jruby system umask is ignored on linux: https://github.com/jruby/jruby/issues/3426 Setting it to -1 uses default OS value. Example: "dir_mode" => 0750

• Value type is number
• Default value is -1

File access mode to use. Note that due to the bug in jruby system umask is ignored on linux: https://github.com/jruby/jruby/issues/3426 Setting it to -1 uses default OS value. Example: "file_mode" => 0640

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

If the generated path is invalid, the events will be saved into this file and inside the defined path.

• Value type is number
• Default value is 2

Flush interval (in seconds) for flushing writes to log files. 0 will flush on every message.

• Value type is boolean
• Default value is false

Gzip the output stream before writing to disk.

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

The path to the file to write. Event fields can be used here, like /var/log/logstash/%{{host}}/%{{application}} One may also utilize the path option for date-based log rotation via the joda time format. This will use the event timestamp. E.g.: path => "./test-%{+YYYY-MM-dd}.txt" to create ./test-2013-05-29.txt

If you use an absolute path you cannot start with a dynamic string. E.g: /%{{myfield}}/, /test-%{{myfield}}/ are not valid paths

• Value type is number
• Default value is 10

Defines the interval, in seconds, between the stale files cleanup runs. The stale files cleanup cycle closes inactive files (i.e files not written to since the last cycle).

• Value type is string
• Default value is append

If append, the file will be opened for appending and each new event will be written at the end of the file. If overwrite, the file will be truncated before writing and only the most recent event will appear in the file.

These configuration options are supported by all output plugins:

• Value type is codec
• Default value is "json_lines"

The codec used for output data. Output codecs are a convenient method for encoding your data before it leaves the output without needing a separate filter in your Logstash pipeline.

• 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 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 file outputs. Adding a named ID in this case will help in monitoring Logstash when using the monitoring APIs.

output {
  file {
    id => "my_plugin_id"
  }
}