Add configurable launch parameters

system_metrics_collector/CMakeLists.txt

@@ -171,8 +171,10 @@ install(TARGETS
   lib/${PROJECT_NAME}
 )
 
-install(TARGETS ${PROJECT_NAME}
-  DESTINATION lib
+install(TARGETS
+  ${PROJECT_NAME}
+  DESTINATION
+  lib
 )
 
 ament_export_libraries(${PROJECT_NAME})

system_metrics_collector/launch/system_cpu_and_memory.launch.py

@@ -12,24 +12,75 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-"""Launch system CPU and system memory metrics collector nodes."""
-
-
 from launch import LaunchDescription
+from launch.actions import DeclareLaunchArgument
+from launch.substitutions import LaunchConfiguration
 from launch_ros.actions import Node
 
+# Launch argument names
+CPU_NODE_NAME = 'linux_cpu_collector_node_name'
+MEMORY_NODE_NAME = 'linux_memory_collector_node_name'
+MEASUREMENT_PERIOD = 'measurement_period'
+PUBLISH_PERIOD = 'publish_period'
+PUBLISH_TOPIC = 'publish_topic'
+
+# Default argument values
+default_cpu_node_name = 'linux_cpu_collector'
+default_memory_node_name = 'linux_memory_collector'
+default_measurement_period_in_ms = '1000'
+default_publish_period_in_ms = '60000'
+default_publish_topic = 'system_metrics'
+
 
 def generate_launch_description():
+    """Launch system CPU and system memory metrics collector nodes."""
+    ld = LaunchDescription()
+
+    ld.add_action(DeclareLaunchArgument(
+        CPU_NODE_NAME,
+        default_value=default_cpu_node_name,
+        description='A custom name for the node that collects the total CPU usage'
+                    ' on a Linux system'))
+    ld.add_action(DeclareLaunchArgument(
+        MEMORY_NODE_NAME,
+        default_value=default_memory_node_name,
+        description='A custom name for the node that collects the total memory usage'
+                    ' on a Linux system'))
+    ld.add_action(DeclareLaunchArgument(
+        MEASUREMENT_PERIOD,
+        default_value=default_measurement_period_in_ms,
+        description='The period (in ms) between each subsequent metrics measurement made'
+                    ' by the collector nodes'))
+    ld.add_action(DeclareLaunchArgument(
+        PUBLISH_PERIOD,
+        default_value=default_publish_period_in_ms,
+        description='The period (in ms) between each subsequent metrics message published'
+                    ' by the collector nodes'))
+    ld.add_action(DeclareLaunchArgument(
+        PUBLISH_TOPIC,
+        default_value=default_publish_topic,
+        description='The name of the topic to which the collector nodes should publish'))
+
+    node_parameters = [
+        {MEASUREMENT_PERIOD: LaunchConfiguration(MEASUREMENT_PERIOD)},
+        {PUBLISH_PERIOD: LaunchConfiguration(PUBLISH_PERIOD)}]
+
     """Run system CPU and memory collector nodes using launch."""
-    ld = LaunchDescription([
+    ld.add_action(
         Node(
             package='system_metrics_collector',
             node_executable='linux_cpu_collector',
-            output='screen'),
+            node_name=LaunchConfiguration(CPU_NODE_NAME),
+            parameters=node_parameters,
+            remappings=[('system_metrics', LaunchConfiguration(PUBLISH_TOPIC))],
+            output='screen'))
+    ld.add_action(
         Node(
             package='system_metrics_collector',
             node_executable='linux_memory_collector',
-            output='screen'
-        ),
-    ])
+            node_name=LaunchConfiguration(MEMORY_NODE_NAME),
+            parameters=node_parameters,
+            remappings=[('system_metrics', LaunchConfiguration(PUBLISH_TOPIC))],
+            output='screen'))
+
     return ld