From bc2d25737e8ef2b492a61687fb37f72324893fcd Mon Sep 17 00:00:00 2001
From: filepang <filepang@lycos.co.kr>
Date: Mon, 1 Aug 2016 12:24:42 +0900
Subject: [PATCH] Allow to search plugin from multiple prefix directory

---
 lib/fluent/plugin.rb   | 14 ++++++------
 lib/fluent/registry.rb | 50 ++++++++++++++++++++++--------------------
 2 files changed, 33 insertions(+), 31 deletions(-)

diff --git a/lib/fluent/plugin.rb b/lib/fluent/plugin.rb
index e970580446..1daa538b63 100644
--- a/lib/fluent/plugin.rb
+++ b/lib/fluent/plugin.rb
@@ -26,15 +26,15 @@ module Plugin
     #   ex: storage, buffer chunk, ...
 
     # first class plugins (instantiated by Engine)
-    INPUT_REGISTRY     = Registry.new(:input,     'fluent/plugin/in_')
-    OUTPUT_REGISTRY    = Registry.new(:output,    'fluent/plugin/out_')
-    FILTER_REGISTRY    = Registry.new(:filter,    'fluent/plugin/filter_')
+    INPUT_REGISTRY     = Registry.new(:input,     'fluent/plugin/in_',        'in_')
+    OUTPUT_REGISTRY    = Registry.new(:output,    'fluent/plugin/out_',       'out_')
+    FILTER_REGISTRY    = Registry.new(:filter,    'fluent/plugin/filter_',    'filter_')
 
     # feature plugin: second class plugins (instanciated by Plugins or Helpers)
-    BUFFER_REGISTRY    = Registry.new(:buffer,    'fluent/plugin/buf_')
-    PARSER_REGISTRY    = Registry.new(:parser,    'fluent/plugin/parser_')
-    FORMATTER_REGISTRY = Registry.new(:formatter, 'fluent/plugin/formatter_')
-    STORAGE_REGISTRY   = Registry.new(:storage,   'fluent/plugin/storage_')
+    BUFFER_REGISTRY    = Registry.new(:buffer,    'fluent/plugin/buf_',       'buf_')
+    PARSER_REGISTRY    = Registry.new(:parser,    'fluent/plugin/parser_',    'parser_')
+    FORMATTER_REGISTRY = Registry.new(:formatter, 'fluent/plugin/formatter_', 'formatter_')
+    STORAGE_REGISTRY   = Registry.new(:storage,   'fluent/plugin/storage_',   'storage_')
 
     REGISTRIES = [INPUT_REGISTRY, OUTPUT_REGISTRY, FILTER_REGISTRY, BUFFER_REGISTRY, PARSER_REGISTRY, FORMATTER_REGISTRY, STORAGE_REGISTRY]
 
diff --git a/lib/fluent/registry.rb b/lib/fluent/registry.rb
index afd66d2e3e..97be1e735f 100644
--- a/lib/fluent/registry.rb
+++ b/lib/fluent/registry.rb
@@ -20,9 +20,9 @@ module Fluent
   class Registry
     DEFAULT_PLUGIN_PATH = File.expand_path('../plugin', __FILE__)
 
-    def initialize(kind, search_prefix)
+    def initialize(kind, *search_prefixes)
       @kind = kind
-      @search_prefix = search_prefix
+      @search_prefixes = search_prefixes
       @map = {}
       @paths = [DEFAULT_PLUGIN_PATH]
     end
@@ -54,32 +54,34 @@ def reverse_lookup(value)
     end
 
     def search(type)
-      path = "#{@search_prefix}#{type}"
+      @search_prefixes.each do |search_prefix|
+        path = "#{search_prefix}#{type}"
 
-      # prefer LOAD_PATH than gems
-      [@paths, $LOAD_PATH].each do |paths|
-        files = paths.map { |lp|
-          lpath = File.expand_path(File.join(lp, "#{path}.rb"))
-          File.exist?(lpath) ? lpath : nil
-        }.compact
-        unless files.empty?
-          # prefer newer version
-          require files.sort.last
-          return
+        # prefer LOAD_PATH than gems
+        [@paths, $LOAD_PATH].each do |paths|
+          files = paths.map { |lp|
+            lpath = File.expand_path(File.join(lp, "#{path}.rb"))
+            File.exist?(lpath) ? lpath : nil
+          }.compact
+          unless files.empty?
+            # prefer newer version
+            require files.sort.last
+            return
+          end
         end
-      end
-
-      specs = Gem::Specification.find_all { |spec|
-        spec.contains_requirable_file? path
-      }
 
-      # prefer newer version
-      specs = specs.sort_by { |spec| spec.version }
-      if spec = specs.last
-        spec.require_paths.each { |lib|
-          file = "#{spec.full_gem_path}/#{lib}/#{path}"
-          require file
+        specs = Gem::Specification.find_all { |spec|
+          spec.contains_requirable_file? path
         }
+
+        # prefer newer version
+        specs = specs.sort_by { |spec| spec.version }
+        if spec = specs.last
+          spec.require_paths.each { |lib|
+            file = "#{spec.full_gem_path}/#{lib}/#{path}"
+            require file
+          }
+        end
       end
     end
   end