Merge pull request elastic#617 from bernd/workaround-slow-openssl-load

Add workaround for slow openssl loading (LOGSTASH-1223)

lib/logstash/JRUBY-6970.rb

@@ -3,11 +3,20 @@ module Kernel
   alias_method :require_JRUBY_6970_hack, :require
 
   def require(path)
+    old_load_path = nil
+
     if path =~ /^jar:file:.+!.+/
       path = path.gsub(/^jar:/, "")
       puts "JRUBY-6970: require(#{path})" if ENV["REQUIRE_DEBUG"] == "1"
     end
 
+    # Work around slow openssl load times in flatjar. (LOGSTASH-1223)
+    if __FILE__ =~ /^(?:jar:)?file:.+!.+/ && path == "openssl"
+      old_load_path = $LOAD_PATH.dup
+      # For some reason loading openssl with an empty LOAD_PATH is fast.
+      $LOAD_PATH.clear
+    end
+
     # JRUBY-7065
     path = File.expand_path(path) if path.include?("/../")
     rc = require_JRUBY_6970_hack(path)
@@ -17,6 +26,8 @@ def require(path)
       require "logstash/JRUBY-6970-openssl"
     end
     return rc
+  ensure
+    $LOAD_PATH.replace(old_load_path) if old_load_path
   end
 end