Upd changelog + ensure drivers loaded once (omission from previous PR) (#348)

* DOH! left over change from previous PR

* Add changelog entries

Author: Guy Boertje

CHANGELOG.md

@@ -1,3 +1,11 @@
+## 4.3.15
+  - Use atomic booleam to load drivers once
+  - Added CHANGELOG entries
+
+## 4.3.14
+  - Added support for driver loading in JDK 9+ [Issue 331](https://github.com/logstash-plugins/logstash-input-jdbc/issues/331)
+  - Gem released without CHANGELOG additions
+
 ## 4.3.13
   - Changed documentation to generalize the PATH location [#297](https://github.com/logstash-plugins/logstash-input-jdbc/pull/297)
 

lib/logstash/plugin_mixins/jdbc/jdbc.rb

@@ -171,22 +171,24 @@ def open_jdbc_connection
       require "sequel/adapters/jdbc"
 
       Sequel.application_timezone = @plugin_timezone.to_sym
-
-      begin
-        load_drivers
-        Sequel::JDBC.load_driver(@jdbc_driver_class)
-      rescue LogStash::Error => e
-        # raised in load_drivers, e.cause should be the caught Java exceptions
-        raise LogStash::PluginLoadingError, "#{e.message} and #{e.cause.message}"
-      rescue Sequel::AdapterNotFound => e
-        # fix this !!!
-        message = if @jdbc_driver_library.nil?
-          ":jdbc_driver_library is not set, are you sure you included
-                    the proper driver client libraries in your classpath?"
-        else
-          "Are you sure you've included the correct jdbc driver in :jdbc_driver_library?"
+      if @drivers_loaded.false?
+        begin
+          load_drivers
+          Sequel::JDBC.load_driver(@jdbc_driver_class)
+        rescue LogStash::Error => e
+          # raised in load_drivers, e.cause should be the caught Java exceptions
+          raise LogStash::PluginLoadingError, "#{e.message} and #{e.cause.message}"
+        rescue Sequel::AdapterNotFound => e
+          # fix this !!!
+          message = if @jdbc_driver_library.nil?
+            ":jdbc_driver_library is not set, are you sure you included
+                      the proper driver client libraries in your classpath?"
+          else
+            "Are you sure you've included the correct jdbc driver in :jdbc_driver_library?"
+          end
+          raise LogStash::PluginLoadingError, "#{e}. #{message}"
         end
-        raise LogStash::PluginLoadingError, "#{e}. #{message}"
+        @drivers_loaded.make_true
       end
       @database = jdbc_connect()
       @database.extension(:pagination)
@@ -226,6 +228,7 @@ def open_jdbc_connection
     public
     def prepare_jdbc_connection
       @connection_lock = ReentrantLock.new
+      @drivers_loaded = Concurrent::AtomicBoolean.new
     end
 
     public

logstash-input-jdbc.gemspec

@@ -1,6 +1,6 @@
 Gem::Specification.new do |s|
   s.name = 'logstash-input-jdbc'
-  s.version         = '4.3.14'
+  s.version         = '4.3.15'
   s.licenses = ['Apache License (2.0)']
   s.summary = "Creates events from JDBC data"
   s.description     = "This gem is a Logstash plugin required to be installed on top of the Logstash core pipeline using $LS_HOME/bin/logstash-plugin install gemname. This gem is not a stand-alone program"