$conf_dir_purge breaks when $agent5_enable is false

[gotyaoi]

If the $conf_dir_purge setting is true and $agent5_enable is false, puppet will purge all the directories of the integrations in conf.d created by first class integration, ie. datadog_agent::integrations::*, and not those created by datadog_agent::integration. It will then try to create the yaml file for the check and fail, as the directory is gone.

This seems to occur because while datadog_agent::integration creates a file resource for the directory when $agent5_enable is false, datadog_agent::integrations::* do not.

[Aramack]

This occurs because the conf_dir_purge value purges untracked files from the conf directoy.
https://github.com/DataDog/puppet-datadog-agent/blob/master/manifests/init.pp#L654

Currently, the integration.d directories within conf.d are created when the agent is installed, but they're not tracked anywhere by puppet.

However, the datadog::integration modules assume the integration.d directories will be present:
https://github.com/DataDog/puppet-datadog-agent/blob/master/manifests/integrations/disk.pp#L59

As a result, having these flags set will result in an error like:

Error: Could not set 'file' on ensure: No such file or directory @ dir_s_mkdir - /etc/datadog-agent/conf.d/disk.d/conf.yaml20190501-1944-1hui08f.lock (file: /etc/puppetlabs/code/puppet-cloud/module-2/datadog_agent/manifests/integrations/disk.pp, line: 67)

Puppet doesn't have a way to recursively create files along a path, so this would need to be fixed by tracking the file with something like:

if !$::datadog_agent::agent5_enable {
  $dst_dir = "${datadog_agent::conf6_dir}/disk.d"
  file { $legacy_dst:
    ensure => 'absent'
  }
  file { $dst_dir:
    ensure  => directory,
    owner   => $datadog_agent::params::dd_user,
    group   => $datadog_agent::params::dd_group,
    mode    => '0755',
    require => Package[$datadog_agent::params::package_name],
    notify  => Service[$datadog_agent::params::service_name]
  }
  $dst = "${dst_dir}/conf.yaml"
else {
  $dst = $legacy_dst
}

I also would like to see a solution to this problem, because using $conf_dir_purge is an effective way to remove a check that is no longer needed from a hosts.