Postgres Adatper SQL Plugin and Nil Pointer Exception

[chris-selinc]

FluentD verison: fluentd 1.17.1
Ruby version: ruby 3.2.5 (2024-07-26 revision 31d0f1a2e7) [x86_64-linux]
Gems:
fluent-plugin-sql (2.3.1)
pg (1.5.9)
This is currently running in a k3s environment.

When using the following configuration for the source in and FluentD:

@type sql
adapter postgresql
host hostname-of-postgres
port 5432
database databaseName
username userName
password passwordForDatabase
tag_prefix postgres
select_interval 5s
state_file /var/run/fluentd/sql_state

table target_table
tag target_table
update_column insertTimestamp


Sometimes I am able to successfully query the database, and other times I am unable to query the database, which results in the following error:
line = caller(depth+1)[0] ^^^ from /usr/local/bundle/gems/fluentd-1.17.1/lib/fluent/log.rb:506:indump_stacktrace'
from /usr/local/bundle/gems/fluentd-1.17.1/lib/fluent/log.rb:389:in warn_backtrace' from /usr/local/bundle/gems/fluentd-1.17.1/lib/fluent/root_agent.rb:287:in rescue in block (3 levels) in shutdown'
from /usr/local/bundle/gems/fluentd-1.17.1/lib/fluent/root_agent.rb:266:in block (3 levels) in shutdown' /usr/local/bundle/gems/fluent-plugin-sql-2.3.1/lib/fluent/plugin/in_sql.rb:252:in shutdown': undefined method `join' for nil:NilClass (NoMethodError)

  @thread.join

`
Sometimes the plugin works as expected, and then I'm able to successfully print out the results.