Request feature to get options of fluent-plugin

[toru-takahashi]

Descriptions

Each fluent-plugin has a lot of option.
Almost users need to choice these options for own use-case.
But, almost user don't know these options.
Therefore, it would be useful for users to show all options of fluent-plugin.

Expected Results

Ex.

> fluentd --show fluent-plugin-s3
    config_param :path, :string, :default => ""
    config_param :use_ssl, :bool, :default => true
    config_param :use_server_side_encryption, :string, :default => nil
    config_param :aws_key_id, :string, :default => nil
    config_param :aws_sec_key, :string, :default => nil
    config_param :s3_bucket, :string
    config_param :s3_region, :string, :default => nil
    config_param :s3_endpoint, :string, :default => nil
    config_param :s3_object_key_format, :string, :default => "%{path}%{time_slice}_%{index}.%{file_extension}"
    config_param :store_as, :string, :default => "gzip"
    config_param :auto_create_bucket, :bool, :default => true
    config_param :check_apikey_on_start, :bool, :default => true
    config_param :proxy_uri, :string, :default => nil
    config_param :reduced_redundancy, :bool, :default => false
    config_param :format, :string, :default => 'out_file'

[kazegusuri]

I like this feature. I and my colleagues often spend time checking how to use plugins by reading upstream source code.
If possible (with self documented api and for supported plugins), it's better to show some examples together.

[tagomoris]

I have some idea to realize this feature:

1. load plugin
2. build configure_proxy tree
3. show it on console

Problems are:

• config_param should accept description option to describe what it is
• default can be overwritten in configure() method in non-declarative way
• type may not be decided in declarative way with config_param w/ blocks

Related: #309

[repeatedly]

Adding desc to config_param could be implemented in v0.12 but it needs extra cost...

[okkez]

I'm trying to implement this feature.

Work like following, for now.

$ bundle exec fluentd --show-plugin-config output:s3
2015-08-26 13:59:43 +0900 [info]: Show config for output:s3
2015-08-26 13:59:43 +0900 [info]: 
path: string: <"">
use_server_side_encryption: string: <nil>
aws_key_id: string: <nil>
aws_sec_key: string: <nil>
s3_bucket: string: <nil>
s3_region: string: <"us-east-1">
s3_endpoint: string: <nil>
s3_object_key_format: string: <"%{path}%{time_slice}_%{index}.%{file_extension}">
store_as: string: <"gzip">
auto_create_bucket: bool: <true>
check_apikey_on_start: bool: <true>
proxy_uri: string: <nil>
reduced_redundancy: bool: <false>
storage_class: string: <"STANDARD">
format: string: <"out_file">
acl: string: <:private>
assume_role_credentials
 role_arn: string: <nil>
 role_session_name: string: <nil>
 policy: string: <nil>
 duration_seconds: integer: <nil>
 external_id: string: <nil>
instance_profile_credentials
 retries: integer: <nil>
 ip_address: string: <nil>
 port: integer: <nil>
 http_open_timeout: float: <nil>
 http_read_timeout: float: <nil>
shared_credentials
 path: string: <nil>
 profile_name: string: <nil>

$ bundle exec fluentd --show-plugin-config input:dummy
2015-08-26 13:59:54 +0900 [info]: Show config for input:dummy
2015-08-26 13:59:54 +0900 [info]: 
tag: string: <nil>
rate: integer: <1>
auto_increment_key: string: <nil>
dummy: : <[{"message"=>"dummy"}]>

[repeatedly]

closed