Support TLS settings when sending to Graylog

[invidian]

As a follow up to #145, it would be great if we could also configure TLS options using env variables.

[invidian]

It seems with this simple configuration snippet:

    protocol "tcp"
    tls true

I get following error:

2019-10-07 13:06:35 +0000 [warn]: #0 [out_graylog] failed to flush the buffer. error_class="NoMethodError" error="undefined method `closed?' for nil:NilClass" plugin_id="out_graylog"
2019-10-07 13:06:35 +0000 [warn]: #0 [out_graylog] got unrecoverable error in primary and no secondary error_class=NoMethodError error="undefined method `closed?' for nil:NilClass"
  2019-10-07 13:06:35 +0000 [warn]: #0 /fluentd/vendor/bundle/ruby/2.6.0/gems/gelf-3.0.0/lib/gelf/transport/tcp.rb:22:in `reject'
  2019-10-07 13:06:35 +0000 [warn]: #0 /fluentd/vendor/bundle/ruby/2.6.0/gems/gelf-3.0.0/lib/gelf/transport/tcp.rb:22:in `block in send'
  2019-10-07 13:06:35 +0000 [warn]: #0 /fluentd/vendor/bundle/ruby/2.6.0/gems/gelf-3.0.0/lib/gelf/transport/tcp.rb:21:in `loop'
  2019-10-07 13:06:35 +0000 [warn]: #0 /fluentd/vendor/bundle/ruby/2.6.0/gems/gelf-3.0.0/lib/gelf/transport/tcp.rb:21:in `send'
  2019-10-07 13:06:35 +0000 [warn]: #0 /fluentd/vendor/bundle/ruby/2.6.0/gems/gelf-3.0.0/lib/gelf/notifier.rb:160:in `notify_with_level!'
  2019-10-07 13:06:35 +0000 [warn]: #0 /fluentd/vendor/bundle/ruby/2.6.0/gems/gelf-3.0.0/lib/gelf/notifier.rb:119:in `notify!'
  2019-10-07 13:06:35 +0000 [warn]: #0 /fluentd/vendor/bundle/ruby/2.6.0/gems/fluent-plugin-gelf-hs-1.0.8/lib/fluent/plugin/out_gelf.rb:92:in `block in write'
  2019-10-07 13:06:35 +0000 [warn]: #0 /fluentd/vendor/bundle/ruby/2.6.0/gems/fluentd-1.7.3/lib/fluent/event.rb:327:in `each'
  2019-10-07 13:06:35 +0000 [warn]: #0 /fluentd/vendor/bundle/ruby/2.6.0/gems/fluentd-1.7.3/lib/fluent/event.rb:327:in `block in each'
  2019-10-07 13:06:35 +0000 [warn]: #0 /fluentd/vendor/bundle/ruby/2.6.0/gems/fluentd-1.7.3/lib/fluent/plugin/buffer/memory_chunk.rb:81:in `open'
  2019-10-07 13:06:35 +0000 [warn]: #0 /fluentd/vendor/bundle/ruby/2.6.0/gems/fluentd-1.7.3/lib/fluent/plugin/buffer/memory_chunk.rb:81:in `open'
  2019-10-07 13:06:35 +0000 [warn]: #0 /fluentd/vendor/bundle/ruby/2.6.0/gems/fluentd-1.7.3/lib/fluent/event.rb:326:in `each'
  2019-10-07 13:06:35 +0000 [warn]: #0 /fluentd/vendor/bundle/ruby/2.6.0/gems/fluent-plugin-gelf-hs-1.0.8/lib/fluent/plugin/out_gelf.rb:90:in `write'
  2019-10-07 13:06:35 +0000 [warn]: #0 /fluentd/vendor/bundle/ruby/2.6.0/gems/fluentd-1.7.3/lib/fluent/compat/output.rb:131:in `write'
  2019-10-07 13:06:35 +0000 [warn]: #0 /fluentd/vendor/bundle/ruby/2.6.0/gems/fluentd-1.7.3/lib/fluent/plugin/output.rb:1125:in `try_flush'
  2019-10-07 13:06:35 +0000 [warn]: #0 /fluentd/vendor/bundle/ruby/2.6.0/gems/fluentd-1.7.3/lib/fluent/plugin/output.rb:1431:in `flush_thread_run'
  2019-10-07 13:06:35 +0000 [warn]: #0 /fluentd/vendor/bundle/ruby/2.6.0/gems/fluentd-1.7.3/lib/fluent/plugin/output.rb:461:in `block (2 levels) in start'
  2019-10-07 13:06:35 +0000 [warn]: #0 /fluentd/vendor/bundle/ruby/2.6.0/gems/fluentd-1.7.3/lib/fluent/plugin_helper/thread.rb:78:in `block in thread_create'
2019-10-07 13:06:35 +0000 [warn]: #0 [out_graylog] bad chunk is moved to /tmp/fluent/backup/worker0/out_graylog/59451b8670de4847070dced66cd07fa7.log

the TLS connection seems fine, when testing with this ruby snippet, which simulates what gelf output plugin is doing:

require 'socket'
require 'openssl'

myXML = '{"version": "1.1","host":"example.org","short_message":"Short message","full_message":"Backtrace here\n\nmore stuff","level":1,"_user_id":9001,"_some_info":"foo","_some_env_var":"bar"}'
host = 'graylog-tcp.graylog'
port = 12222

socket = TCPSocket.open(host,port)
ssl_context = OpenSSL::SSL::SSLContext.new()
ssl_context.cert_store = OpenSSL::X509::Store.new.tap do |store|
  store.set_default_paths
end
ssl_socket = OpenSSL::SSL::SSLSocket.new(socket, ssl_context)
ssl_socket.sync_close = true
ssl_socket.connect

ssl_socket.puts(myXML)
ssl_socket.close

It looks like https://github.com/hotschedules/fluent-plugin-gelf-hs/releases/tag/1.0.8 still use 3.0.0 version of gelf-rb and 3.1.0 is available already: https://github.com/graylog-labs/gelf-rb/releases/tag/v3.1.0, which contains a lot of new options and fixes.

[repeatedly]

gelf-rb has critical bug for fluentd and it is not fixed yet.

graylog-labs/gelf-rb#87

Please ping gelf-rb developers to fix the json issue.

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[github-actions]

This issue was automatically closed because of stale in 30 days

[ciastooo]

@invidian, @repeatedly seems like gelf-rb is no longer maintained. Is there any other way to resolve this error? Seems like it makes setting up tls impossible