Can not ship logs to elasticsearch ? any idea

{:timestamp=>"2016-07-01T18:57:37.916000+0000", :message=>"Failed to flush outgoing items", :outgoing_count=>1, :exception=>"NoMethodError", :backtrace=>["/opt/logstash/vendor/bundle/jruby/1.9/gems/aws-sdk-core-2.1.36/lib/aws-sdk-core/signers/v4.rb:24:in initialize'", "/opt/logstash/vendor/bundle/jruby/1.9/gems/logstash-output-amazon_es-1.0-java/lib/logstash/outputs/amazon_es/aws_v4_signer_impl.rb:36:insigner'", "/opt/logstash/vendor/bundle/jruby/1.9/gems/logstash-output-amazon_es-1.0-java/lib/logstash/outputs/amazon_es/aws_v4_signer_impl.rb:48:in call'", "/opt/logstash/vendor/bundle/jruby/1.9/gems/faraday-0.9.2/lib/faraday/rack_builder.rb:139:inbuild_response'", "/opt/logstash/vendor/bundle/jruby/1.9/gems/faraday-0.9.2/lib/faraday/connection.rb:377:in run_request'", "/opt/logstash/vendor/bundle/jruby/1.9/gems/logstash-output-amazon_es-1.0-java/lib/logstash/outputs/amazon_es/aws_transport.rb:49:inperform_request'", "org/jruby/RubyProc.java:281:in call'", "/opt/logstash/vendor/bundle/jruby/1.9/gems/elasticsearch-transport-1.0.17/lib/elasticsearch/transport/transport/base.rb:257:inperform_request'", "/opt/logstash/vendor/bundle/jruby/1.9/gems/logstash-output-amazon_es-1.0-java/lib/logstash/outputs/amazon_es/aws_transport.rb:45:in perform_request'", "/opt/logstash/vendor/bundle/jruby/1.9/gems/elasticsearch-transport-1.0.17/lib/elasticsearch/transport/client.rb:128:inperform_request'", "/opt/logstash/vendor/bundle/jruby/1.9/gems/elasticsearch-api-1.0.17/lib/elasticsearch/api/actions/bulk.rb:88:in bulk'", "/opt/logstash/vendor/bundle/jruby/1.9/gems/logstash-output-amazon_es-1.0-java/lib/logstash/outputs/amazon_es/http_client.rb:53:inbulk'", "/opt/logstash/vendor/bundle/jruby/1.9/gems/logstash-output-amazon_es-1.0-java/lib/logstash/outputs/amazon_es.rb:321:in submit'", "org/jruby/ext/thread/Mutex.java:149:insynchronize'", "/opt/logstash/vendor/bundle/jruby/1.9/gems/logstash-output-amazon_es-1.0-java/lib/logstash/outputs/amazon_es.rb:318:in submit'", "/opt/logstash/vendor/bundle/jruby/1.9/gems/logstash-output-amazon_es-1.0-java/lib/logstash/outputs/amazon_es.rb:351:inflush'", "/opt/logstash/vendor/bundle/jruby/1.9/gems/stud-0.0.22/lib/stud/buffer.rb:219:in buffer_flush'", "org/jruby/RubyHash.java:1342:ineach'", "/opt/logstash/vendor/bundle/jruby/1.9/gems/stud-0.0.22/lib/stud/buffer.rb:216:in buffer_flush'", "/opt/logstash/vendor/bundle/jruby/1.9/gems/stud-0.0.22/lib/stud/buffer.rb:193:inbuffer_flush'", "/opt/logstash/vendor/bundle/jruby/1.9/gems/stud-0.0.22/lib/stud/buffer.rb:159:in buffer_receive'", "/opt/logstash/vendor/bundle/jruby/1.9/gems/logstash-output-amazon_es-1.0-java/lib/logstash/outputs/amazon_es.rb:311:inreceive'", "/opt/logstash/vendor/bundle/jruby/1.9/gems/logstash-core-2.3.2-java/lib/logstash/outputs/base.rb:83:in multi_receive'", "org/jruby/RubyArray.java:1613:ineach'", "/opt/logstash/vendor/bundle/jruby/1.9/gems/logstash-core-2.3.2-java/lib/logstash/outputs/base.rb:83:in multi_receive'", "/opt/logstash/vendor/bundle/jruby/1.9/gems/logstash-core-2.3.2-java/lib/logstash/output_delegator.rb:130:inworker_multi_receive'", "/opt/logstash/vendor/bundle/jruby/1.9/gems/logstash-core-2.3.2-java/lib/logstash/output_delegator.rb:114:in multi_receive'", "/opt/logstash/vendor/bundle/jruby/1.9/gems/logstash-core-2.3.2-java/lib/logstash/pipeline.rb:301:inoutput_batch'", "org/jruby/RubyHash.java:1342:in each'", "/opt/logstash/vendor/bundle/jruby/1.9/gems/logstash-core-2.3.2-java/lib/logstash/pipeline.rb:301:inoutput_batch'", "/opt/logstash/vendor/bundle/jruby/1.9/gems/logstash-core-2.3.2-java/lib/logstash/pipeline.rb:232:in worker_loop'", "/opt/logstash/vendor/bundle/jruby/1.9/gems/logstash-core-2.3.2-java/lib/logstash/pipeline.rb:201:instart_workers'"], :level=>:warn}

How about providing your config as well?
What version are you on?

logstash: 2.3.2
elasticsearch: aws es (1.5)

input {
beats {
port => 5044
ssl => true
ssl_certificate_authorities => ["/etc/logstash/certs/ca.crt"]
ssl_certificate => "/etc/logstash/certs/server.crt"
ssl_key => "/etc/logstash/certs/server.key"
ssl_verify_mode => "force_peer"
congestion_threshold => 40
}
}
output {
amazon_es {
hosts => ["search-elk-test-*8.us-west-2.es.amazonaws.com"]
region => "us-west-2"
}
stdout { codec => rubydebug }
}