[BUG]: Error with APM on pg traces sicne updating to 2.x

[wyardley]

Tracer Version(s)

2.8.0

Ruby Version(s)

ruby 3.3.6 (2024-11-05 revision 75015d4c1f) [x86_64-linux-musl]

Relevent Library and Version(s)

pg (1.4.1)

Bug Report

Since updating to 2.x, we're seeing this error:

E, [2025-01-06T10:22:31.740031 #56844] ERROR -- datadog: [datadog] (/usr/local/bundle/gems/datadog-2.8.0/lib/datadog/tracing/contrib/active_record/events/sql.rb:72:in `rescue in on_start') You can't invoke instance_variable_get on #<ActiveRecord::ConnectionAdapters::PostgreSQLAdapter:0x00007f0793ed89a0>

The APM is being initialized in a pretty vanilla way, I think (leaving out some of the irrelevant config options):

Reproduction Code

No response

Configuration Block

Datadog.configure do |c|
  if enable_datadog
    require "datadog/auto_instrument"
    c.tracing.instrument :pg, comment_propagation: "full"
    # [...]
end

Error Logs

E, [2025-01-06T10:22:31.740031 #56844] ERROR -- datadog: [datadog] (/usr/local/bundle/gems/datadog-2.8.0/lib/datadog/tracing/contrib/active_record/events/sql.rb:72:in `rescue in on_start') You can't invoke instance_variable_get on #<ActiveRecord::ConnectionAdapters::PostgreSQLAdapter:0x00007f0793ed89a0>

Operating System

Linux cd8a7bf08538 6.10.14-linuxkit #1 SMP

How does Datadog help you?

No response

[wyardley]

I came across #4179, but don't think it's related.

[wyardley]

Issue turned out to be in rails console only, and related to a gem that interfered with the APM, so this is resolved now.

[ivoanjo]

Thanks for letting us know @wyardley 🙏