Plugin Helper: Formatter

The formatter plugin helper manages the lifecycle of formatter plugin.

Here is an example:

require 'fluent/plugin/output'
module Fluent::Plugin
class ExampleOutput < Output
Fluent::Plugin.register_output('example', self)
# 1. Load formatter helper
helpers :formatter
# Omit `shutdown` and other plugin APIs
def configure(conf)
super
# 2. Call `formatter_create` to create object
@formatter = formatter_create(usage: 'awesome_formatter')
end
def format(tag, time, record)
# 3. Call `format` method to format `record`
@formatter.format(tag, time, record)
end
end
end

For more details, see the following articles:

Methods

formatter_create(usage: "", type: nil, conf: nil, default_type: nil)

  • usage: unique name required for multiple formatters

  • type: formatter type

  • conf: formatter plugin configuration

  • default_type: default formatter type

Examples:

def configure(conf)
super
# Create formatter plugin instance using <format> section in `fluent.conf` during configure phase
@formatter = formatter_create
end
def format(tag, time, record)
@formatter.format(tag, time, record)
end

JSON formatter example:

# Create JSON formatter
def configure(conf)
super
@json_formatter = formatter_create(usage: 'formatter_in_example_json', type: 'json')
end
def format(tag, time, record)
@json_formatter.format(tag, time, record)
end

MsgPack formatter example:

# Create MsgPack formatter
def configure(conf)
super
@msgpack_formatter = formatter_create(usage: 'formatter_in_example_msgpack', type: 'msgpack')
end
def format(tag, time, record)
@msgpack_formatter.format(tag, time, record)
end

Plugins using formatter

If this article is incorrect or outdated, or omits critical information, please let us know. Fluentd is an open-source project under Cloud Native Computing Foundation (CNCF). All components are available under the Apache 2 License.