Merge pull request #1482 from okkez/storage-create-can-accept-hash

Fix a bug storage_create cannot accept hash as `conf` keyword argument

lib/fluent/plugin_helper/storage.rb

@@ -30,7 +30,7 @@ module Storage
       StorageState = Struct.new(:storage, :running)
 
       def storage_create(usage: '', type: nil, conf: nil, default_type: nil)
-        if conf && !conf.arg.empty?
+        if conf && conf.respond_to?(:arg) && !conf.arg.empty?
           usage = conf.arg
         end
         if !usage.empty? && usage !~ /^[a-zA-Z][-_.a-zA-Z0-9]*$/

test/plugin_helper/test_storage.rb

@@ -99,6 +99,15 @@ class Dummy2 < Fluent::Plugin::TestBase
     assert_equal 0, d._storages.size
   end
 
+  test 'can be configured with hash' do
+    d = Dummy.new
+    d.configure(config_element())
+    conf = { '@type' => 'example' }
+    assert_nothing_raised do
+      d.storage_create(conf: conf)
+    end
+  end
+
   test 'can override default configuration parameters, but not overwrite whole definition' do
     d = Dummy.new
     d.configure(config_element())