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+---
+title: How to extend - logstash
+layout: content_right
+---
+# Extending logstash
+
+You can add your own input, output, or filter plugins to logstash.
+
+DOCS - TBD
+
+If you're looking to extend logstash today, please look at the existing plugins.
+
+Good examples include:
+
+* [inputs/beanstalk](https://github.com/logstash/logstash/blob/master/lib/logstash/inputs/beanstalk.rb)
+* [filters/multiline](https://github.com/logstash/logstash/blob/master/lib/logstash/filters/multiline.rb)
+* [outputs/mongodb](https://github.com/logstash/logstash/blob/master/lib/logstash/outputs/mongodb.rb)
+
+Main stuff you need to know:
+
+* 'config_name' sets the name used in the config file.
+* 'config' lines define config options
+* 'register' method is called per plugin instantiation. Do any of your initialization here.
+
+Inputs have two methods: register and run.
+
+* Each input runs as it's own thread.
+* the 'run' method is expected to run-forever.
+
+Filters have two methods: register and filter.
+
+* 'filter' method gets an event. 
+* Call 'event.cancel' to drop the event.
+* To modify an event, simply make changes to the event you are given.
+* The return value is ignored.
+
+Outputs have two methods: register and receive.
+
+* 'register' is called per plugin instantiation. Do any of your initialization here.
+* 'receive' is called when an event gets pushed to your output

- add extending docs