org.jruby.exceptions.RaiseException: (LoadError) no such file to load -- toml-rb about puppet-telegraf HOT 2 OPEN

Came here with the same issue. Solved by
systemctl restart puppetserver.service
So, could you please update project README.md, looks like it's the necessary step.

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for puppet server 6 + run this on the server

/opt/puppetlabs/server/bin/puppetserver gem install toml-rb
systemctl restart puppetserver.service

dont forget to restart the puppetserver service

you can do it via the puppetserver_gem package provider
puppet module install puppetlabs-puppetserver_gem

control repo

mod 'puppetlabs-puppetserver_gem', '1.1.0'

then on your puppet server manifest

    ensure_packages(
      ['toml-rb'],
      {ensure   => 'present', provider => 'puppetserver_gem' }
    )

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