wrong argument type nil (expected String)

[belongstorachel]

We recently upgraded our Ruby version of our application to 3.1.2. We are currently using Rails 6.0.

It seems that since our Ruby upgrade, the ruby-analytics gem throws "[analytics-ruby] wrong argument type nil (expected String)" We recently increased the amount of track & identify calls we are making to Segment and the instances of these errors are growing.

We are calling if Analytics.queued_messages >= 9_000

This is the stack trace that we have. (Note that the last line is what we have in the on_error: Proc.new { |status, msg| puts "Segment Error: #{status}, #{msg}" })

14:48:30.844
[analytics-ruby] wrong argument type nil (expected String)

14:48:30.844
[analytics-ruby] /app/vendor/bundle/ruby/3.1.0/gems/activesupport-6.0.6.1/lib/active_support/core_ext/object/json.rb:39:in `to_json'

14:48:30.845
[analytics-ruby] /app/vendor/ruby-3.1.2/lib/ruby/3.1.0/forwardable.rb:238:in `to_json'

14:48:30.845
[analytics-ruby] /app/vendor/bundle/ruby/3.1.0/gems/analytics-ruby-2.4.0/lib/segment/analytics/transport.rb:110:in `generate'

14:48:30.845
[analytics-ruby] /app/vendor/bundle/ruby/3.1.0/gems/analytics-ruby-2.4.0/lib/segment/analytics/transport.rb:110:in `send_request'

14:48:30.845
[analytics-ruby] /app/vendor/bundle/ruby/3.1.0/gems/analytics-ruby-2.4.0/lib/segment/analytics/transport.rb:42:in `block in send'

14:48:30.845
[analytics-ruby] /app/vendor/bundle/ruby/3.1.0/gems/analytics-ruby-2.4.0/lib/segment/analytics/transport.rb:92:in `retry_with_backoff'

14:48:30.845
[analytics-ruby] /app/vendor/bundle/ruby/3.1.0/gems/analytics-ruby-2.4.0/lib/segment/analytics/transport.rb:92:in `retry_with_backoff'

14:48:30.845
[analytics-ruby] /app/vendor/bundle/ruby/3.1.0/gems/analytics-ruby-2.4.0/lib/segment/analytics/transport.rb:102:in `retry_with_backoff'

14:48:30.845
[analytics-ruby] /app/vendor/bundle/ruby/3.1.0/gems/analytics-ruby-2.4.0/lib/segment/analytics/transport.rb:102:in `retry_with_backoff'

14:48:30.845
[analytics-ruby] /app/vendor/bundle/ruby/3.1.0/gems/analytics-ruby-2.4.0/lib/segment/analytics/transport.rb:102:in `retry_with_backoff'

14:48:30.845
[analytics-ruby] /app/vendor/bundle/ruby/3.1.0/gems/analytics-ruby-2.4.0/lib/segment/analytics/transport.rb:102:in `retry_with_backoff'

14:48:30.845
[analytics-ruby] /app/vendor/bundle/ruby/3.1.0/gems/analytics-ruby-2.4.0/lib/segment/analytics/transport.rb:102:in `retry_with_backoff'

14:48:30.845
[analytics-ruby] /app/vendor/bundle/ruby/3.1.0/gems/analytics-ruby-2.4.0/lib/segment/analytics/transport.rb:102:in `retry_with_backoff'

14:48:30.845
[analytics-ruby] /app/vendor/bundle/ruby/3.1.0/gems/analytics-ruby-2.4.0/lib/segment/analytics/transport.rb:102:in `retry_with_backoff'

14:48:30.845
[analytics-ruby] /app/vendor/bundle/ruby/3.1.0/gems/analytics-ruby-2.4.0/lib/segment/analytics/transport.rb:41:in `send'

14:48:30.845
[analytics-ruby] /app/vendor/bundle/ruby/3.1.0/gems/analytics-ruby-2.4.0/lib/segment/analytics/worker.rb:45:in `run'

14:48:30.845
[analytics-ruby] /app/vendor/bundle/ruby/3.1.0/gems/analytics-ruby-2.4.0/lib/segment/analytics/client.rb:191:in `block (2 levels) in ensure_worker_running'

14:48:30.845
Segment Error: -1, wrong argument type nil (expected String)

[belongstorachel]

We found the source of this issue. It has to do with a newer version of the oj gem. We were previously at 3.10.14, and upgraded to 3.14.3 which caused this error. When we reverted it back to 3.10.14, it stopped generating this error.