Does fluentd loads gem in alphabetical order of their name?

[RamHaridas]

I have installed 2 gems fluent-plugin-splunk-enterprise and fluent-plugin-splunk-hec. Both gems have a plugin with same name @type splunk_hec.
This creates a situation where splunk-hec overrides the type name to its own parameters, ending up in a situation where fluentd fails if @type splunk_hec is used with parameters of splunk-enterprise.

Now I do understand that this a default known behavior of fluentd where type names are registered uniquely.

In order to understand and overcome this, I installed both gems at different paths and tried loading them in different order using GEM_PATH environment variable.

• Installed splunk-hec at /path/to/splunk-hec
• Installed splunk-enterprise at /path/to/splunk-enterprise

Then I tried loading them through GEM_PATH in different ways:

• GEM_PATH="/default/path:/path/to/splunk-hec:/path/to/splunk-enterprise"
• GEM_PATH="/default/path:/path/to/splunk-enterprise:/path/to/splunk-hec"

I even tried installing gems in a chronological order:

1. Installed HEC first, then ENTERPRISE
2. Installed ENTERPRISE first, then HEC

Regardless of how gems are installed or loaded, fluentd would still load HEC plugin second which ends up overriding the splunk_hec type.

I wanted to understand the order in which fluentd is loading gems. Is it in alphabetical order?
Because every time fluent-plugin-splunk-hec is loaded second leading it to register type name splunk_hec for itself.

[Watson1978]

Basically depends on the version number included in the path.

fluentd/lib/fluent/registry.rb

Lines 85 to 89 in 7ba2227

	unless files.empty?
	# prefer newer version
	require files.max
	return
	end

By default, it prioritizes loading the latest version.

irb(main):005> ['1.1', '1.2'].max
=> "1.2"
irb(main):006> ['1.3', '1.2'].max
=> "1.3"
irb(main):007> ['1.2.1', '1.2'].max
=> "1.2.1"

If it conflicts with another gem, the result may differ because the paths are different....
it depends on comparison results between strings.

irb(main):008> ['a1.2', 'b1.2'].max
=> "b1.2"

[Watson1978]

it would be preferable to use properly maintained plugins.
Can you look #5156 ?

[RamHaridas]

Thank you for your reply @Watson1978 . I understand that for same gems, the max version would be loaded by fluentd.
But I wanted to confirm whether the order of loading plugins and registering their type name is done alphabetically or not? (because the observation made in my validations leads me to believe so)

[Watson1978]

Try investigating Ruby's behavior to determine what ['StringA', 'StringB'].max would return.

[RamHaridas]

Looks like alphabetically descending to me 🙂