Bugfix: implemented close method for release of resources

close method is used to clean in case of error in run phase of the plugin, implemented to avoid leak of threads generated by Rufus scheduler.

Fixes #21
Close #28

Author: andsel

CHANGELOG.md

@@ -1,3 +1,6 @@
+## 5.0.2
+  - Fixed potential resource leak by ensuring scheduler is shutdown when a pipeline encounter an error during the running [#28](https://github.com/logstash-plugins/logstash-integration-jdbc/pull/28)
+  
 ## 5.0.1
   - Fixed tracking_column regression with Postgresql Numeric types [#17](https://github.com/logstash-plugins/logstash-integration-jdbc/pull/17)
   - Fixed driver loading when file not accessible [#15](https://github.com/logstash-plugins/logstash-integration-jdbc/pull/15)

lib/logstash/inputs/jdbc.rb

@@ -283,6 +283,10 @@ def run(queue)
     end
   end # def run
 
+  def close
+    @scheduler.shutdown if @scheduler
+  end
+
   def stop
     close_jdbc_connection
     @scheduler.shutdown(:wait) if @scheduler

logstash-integration-jdbc.gemspec

@@ -1,6 +1,6 @@
 Gem::Specification.new do |s|
   s.name = 'logstash-integration-jdbc'
-  s.version         = '5.0.1'
+  s.version         = '5.0.2'
   s.licenses = ['Apache License (2.0)']
   s.summary         = "Integration with JDBC - input and filter plugins"
   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"

spec/inputs/jdbc_spec.rb

@@ -191,6 +191,18 @@
       Timecop.return
     end
 
+    it "cleans up scheduler resources on close" do
+      runner = Thread.new do
+        plugin.run(queue)
+      end
+      sleep 1
+      plugin.do_close
+
+      scheduler = plugin.instance_variable_get(:@scheduler)
+      expect(scheduler).to_not be_nil
+      expect(scheduler.down?).to be_truthy
+    end
+
   end
 
   context "when scheduling and previous runs are to be preserved" do