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MessagePack codec and Logstash 2.3 distribution still use old msgpack-jruby gem

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
30/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Stale
Tech stack
ruby
Domain
backend

Research direction

No files or tests are named. Start by locating the MessagePack codec implementation and the Logstash 2.3 distribution dependency definition, then trace how input is parsed and output is packed. Done means both use the msgpack gem, support STR8 and BIN messages, and have coverage for the reported parsing errors and compatibility behavior.

Written by the indexing model from the issue text.

Description

The msgpack-jruby gem has been deprecated and does not support the new STR8 and BIN types in the MessagePack format. The msgpack gem should be used instead.

This old version of msgpack-jruby gives errors like the following when parsing messages from new the new msgpack gem:

Trouble parsing msgpack input, falling back to plain text {:input=>"...", :exception=>java.io.IOException: Invalid byte: -60, :level=>:warn}
Trouble parsing msgpack input, falling back to plain text {:input=>"...", :exception=>java.io.IOException: Invalid byte: -39, :level=>:warn}

A temporary workaround is to pass the compatibility_mode: true option (or similar in other languages) to MessagePack.pack in all clients that might send events to Logstash. This codec should probably use that option for output messages as well, after switching to the msgpack gem.

Additional references:

Dominant language
Ruby
Stars
5
Forks
10
PR merge metrics
No merged PRs in 30d

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