[puppet] Add option to set service CLI arg (#6286)

Author: pjanotti

deployments/puppet/CHANGELOG.md

@@ -2,6 +2,12 @@
 
 ## Unreleased
 
+### 💡 Enhancements 💡
+
+- Add support for the `collector_command_line_args` option to
+  configure the command line arguments for the Splunk OpenTelemetry Collector
+  service.
+
 ## puppet-v0.18.0
 
 - Breaking change: The default for the `auto_instrumentation_otlp_endpoint` option has been changed from

deployments/puppet/README.md

@@ -68,6 +68,7 @@ This class accepts the following parameters:
 | `splunk_memory_total_mib`            | Total memory in MIB to allocate to the collector.  The `SPLUNK_MEMORY_TOTAL_MIB` environment variable will be set with this value for the collector service.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                | `512`                                                                                                                         |
 |**DEPRECATED** `splunk_ballast_size_mib`            | Set the ballast size for the collector explicitly instead of the value calculated from the `$splunk_memory_total_mib` parameter.  This should be set to 1/3 to 1/2 of configured memory.  The `SPLUNK_BALLAST_SIZE_MIB` environment variable will be set with this value for the collector service. Only applicable if `collector_version` is < 0.97.0.                                                                                                                                                                                                                                                                                     | None                                                                                                                          |
 | `splunk_listen_interface`            | Set the network interface the collector receivers will listen on.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           | `0.0.0.0`                                                                                                                     |
+| `collector_command_line_args`        | Command-line arguments to pass to the collector service. The `OTELCOL_OPTIONS` environment variable will be set with this value for the collector service.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                | None                                                                                                                          |
 | `collector_config_source`            | Source path to the collector config YAML file. This file will be copied to the `$collector_config_dest` path on the node.  See the [source attribute](https://puppet.com/docs/puppet/latest/types/file.html#file-attribute-source) of the `file` resource for supported value types.  The default source file is provided by the collector package.                                                                                                                                                                                                                                                                                         | Linux: `/etc/otel/collector/agent_config.yaml`<br>Windows: `%PROGRAMFILES\Splunk\OpenTelemetry Collector\agent_config.yaml`   |
 | `collector_config_dest`              | Destination path of the collector config file on the node.  The `SPLUNK_CONFIG` environment variable will be set with this value for the collector service.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 | Linux: `/etc/otel/collector/agent_config.yaml`<br>Windows: `%PROGRAMDATA%\Splunk\OpenTelemetry Collector\agent_config.yaml`   |
 | `service_user` and `$service_group`  | **Linux only**: Set the user/group ownership for the collector service. The user/group will be created if they do not exist.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                | `splunk-otel-collector`                                                                                                       |

deployments/puppet/manifests/init.pp

@@ -10,6 +10,7 @@
   $splunk_collectd_dir     = $splunk_otel_collector::params::splunk_collectd_dir,
   $splunk_memory_total_mib = '512',
   $splunk_listen_interface = '',
+  $collector_command_line_args = '',
   $collector_version       = $splunk_otel_collector::params::collector_version,
   $collector_config_source = $splunk_otel_collector::params::collector_config_source,
   $collector_config_dest   = $splunk_otel_collector::params::collector_config_dest,

deployments/puppet/templates/splunk-otel-collector.conf.erb

@@ -14,6 +14,9 @@ SPLUNK_REALM=<%= @splunk_realm %>
 <% unless @gomemlimit.to_s.strip.empty? -%>
 GOMEMLIMIT=<%= @gomemlimit %>
 <% end -%>
+<% unless @collector_command_line_args.to_s.strip.empty? -%>
+OTELCOL_OPTIONS=<%= @collector_command_line_args %>
+<% end -%>
 
 # Custom environment variables.
 <% @collector_additional_env_vars.each do |key, value| %>

packaging/tests/deployments/puppet/puppet_test.py

@@ -188,6 +188,7 @@ class {{ splunk_otel_collector:
     splunk_listen_interface => '0.0.0.0',
     collector_version => '$version',
     with_fluentd => true,
+    collector_command_line_args => '--discovery',
     collector_additional_env_vars => {{ 'MY_CUSTOM_VAR1' => 'value1', 'MY_CUSTOM_VAR2' => 'value2' }},
 }}
 """
@@ -219,6 +220,7 @@ def test_puppet_with_custom_vars(distro, puppet_release):
             verify_package_version(container, "splunk-otel-collector", "0.86.0")
             verify_env_file(container, api_url, ingest_url, "fake-hec-token")
             verify_config_file(container, SPLUNK_ENV_PATH, "SPLUNK_LISTEN_INTERFACE", "0.0.0.0")
+            verify_config_file(container, SPLUNK_ENV_PATH, "OTELCOL_OPTIONS", "--discovery")
             verify_config_file(container, SPLUNK_ENV_PATH, "MY_CUSTOM_VAR1", "value1")
             verify_config_file(container, SPLUNK_ENV_PATH, "MY_CUSTOM_VAR2", "value2")
             assert wait_for(lambda: service_is_running(container))