Duplicate package resource when manage_install is false and package is declared outside of module

[jmcnatt]

Scenario

For module users that use resource-style declarations, integration classes become unusable due to the require datadog_agent declaration in each integration class.

Consider the following snippet:

  $package_name = 'datadog-agent'

  # Install the package
  package { $package_name:
    ensure          => present,
    provider        => $package_provider,
    install_options => $install_options,
  }

  # Implement the module
  class { 'datadog_agent':
    dd_user        => $dd_user,
    dd_group       => $dd_group,
    manage_install => false,
    require        => Package[$package_name],
  }

  class { 'datadog_agent::integrations::disk':
    use_mount          => 'no',
    filesystem_exclude => [
      'none',
      'tmpfs',
      'tracefs',
      'squashfs',
    ],
  }

This implementation results in

Error: Could not retrieve catalog from remote server: Error 500 on SERVER: Server Error: Evaluation Error: Error while evaluating a Resource Statement, Evaluation Error: Error while evaluating a Resource Statement, Duplicate declaration: Package[datadog-agent] is already declared at (file: /etc/puppetlabs/code/environments/test/modules/datadog_agent/manifests/init.pp, line: 491); cannot redeclare...

Proposal

The require datadog_agent statement in each module is not necessary, especially given many of the resources already contain statements to require datadog_agent::params::package_name.

Additional Background

My org must implement additional logic to install the datadog-agent package outside of this module, mainly due to limitations of the module (See #742 and #747) and would like to utilize the integration classes as well.