Port hd_monitor to ROS2 (#334)

* Port hd_monitor.py
* Adapt documentation and CMakeList to new hd_monitor.py
* Fix execution flag of hd_monitor
* Add launch test for hd_monitor
* Implement low and crit parameters in hd_monitor
* Improve hd_monitor code quality

(cherry picked from commit 05a9645)

diagnostic_common_diagnostics/CMakeLists.txt

@@ -12,6 +12,7 @@ install(PROGRAMS
     ${PROJECT_NAME}/ntp_monitor.py
     ${PROJECT_NAME}/ram_monitor.py
     ${PROJECT_NAME}/sensors_monitor.py
+    ${PROJECT_NAME}/hd_monitor.py
     DESTINATION lib/${PROJECT_NAME}
 )
 
@@ -29,6 +30,10 @@ if(BUILD_TESTING)
         test/systemtest/test_ntp_monitor_launchtest.py
         TARGET ntp_monitor_launchtest
         TIMEOUT 20)
+    add_launch_test(
+        test/systemtest/test_hd_monitor_launchtest.py
+        TARGET hd_monitor_launchtest
+        TIMEOUT 20)
 endif()
 
 ament_package()

diagnostic_common_diagnostics/README.md

@@ -67,7 +67,20 @@ Computer name in diagnostics output (ex: 'c1')
 Disable self test.
 
 ## hd_monitor.py
-**To be ported**
+Runs 'shutil.disk_usage' to check if there is enough space left on a given device.
+* Above 5% of free space left, an `OK` status will be published.
+* Between 5% and 1%, a `WARN` status will be published,
+* Below 1%, an `ERROR` status will be published.
+
+### Published Topics
+#### /diagnostics
+diagnostic_msgs/DiagnosticArray
+The diagnostics information.
+
+### Parameters
+#### path
+(default: home directory "~")
+Path in which to check remaining space.
 
 ## ram_monitor.py
 The `ram_monitor` module allows users to monitor the RAM usage of their system in real-time.

diagnostic_common_diagnostics/diagnostic_common_diagnostics/hd_monitor.py

@@ -0,0 +1,153 @@
+#! /usr/bin/env python3
+"""Hard Drive (or any other memory) monitor. Contains a the monitor node and its main function."""
+# -*- coding: utf-8 -*-
+#
+# Software License Agreement (BSD License)
+#
+# Copyright (c) 2009, Willow Garage, Inc.
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+#
+#  * Redistributions of source code must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+#  * Redistributions in binary form must reproduce the above
+#    copyright notice, this list of conditions and the following
+#    disclaimer in the documentation and/or other materials provided
+#    with the distribution.
+#  * Neither the name of the Willow Garage nor the names of its
+#    contributors may be used to endorse or promote products derived
+#    from this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+# FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+# COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+# BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+# LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+# ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+# POSSIBILITY OF SUCH DAMAGE.
+
+# \author Kevin Watts
+# \author Antoine Lima
+
+from pathlib import Path
+from shutil import disk_usage
+from socket import gethostname
+from typing import List
+
+from diagnostic_msgs.msg import DiagnosticStatus, KeyValue
+from diagnostic_updater import Updater
+from rcl_interfaces.msg import SetParametersResult
+import rclpy
+from rclpy.node import Node
+
+
+FREE_PERCENT_LOW = 0.05
+FREE_PERCENT_CRIT = 0.01
+DICT_STATUS = {
+    DiagnosticStatus.OK: 'OK',
+    DiagnosticStatus.WARN: 'Warning',
+    DiagnosticStatus.ERROR: 'Error',
+}
+DICT_USAGE = {
+    DiagnosticStatus.OK: 'OK',
+    DiagnosticStatus.WARN: 'Low Disk Space',
+    DiagnosticStatus.ERROR: 'Very Low Disk Space',
+}
+
+
+class HDMonitor(Node):
+    """Diagnostic node checking the remaining space on the specified hard drive.
+
+    Three ROS parameters:
+    - path: Path on the filesystem to check (string, default: home directory)
+    - free_percent_low: Percentage at which to consider the space left as low
+    - free_percent_crit: Percentage at which to consider the space left as critical
+    """
+
+    def __init__(self):
+        hostname = gethostname().replace('.', '_').replace('-', '_')
+        super().__init__(f'hd_monitor_{hostname}')
+
+        self._path = '~'
+        self._free_percent_low = 0.05
+        self._free_percent_crit = 0.01
+
+        self.add_on_set_parameters_callback(self.callback_config)
+        self.declare_parameter('path', self._path)
+        self.declare_parameter('free_percent_low', self._free_percent_low)
+        self.declare_parameter('free_percent_crit', self._free_percent_crit)
+
+        self._updater = Updater(self)
+        self._updater.setHardwareID(hostname)
+        self._updater.add(f'{hostname} HD Usage', self.check_disk_usage)
+
+    def callback_config(self, params: List[rclpy.Parameter]):
+        """Retrieve ROS parameters.
+
+        see the class documentation for declared parameters.
+        """
+        for param in params:
+            match param.name:
+                case 'path':
+                    self._path = str(
+                        Path(param.value).expanduser().resolve(strict=True)
+                    )
+                case 'free_percent_low':
+                    self._free_percent_low = param.value
+                case 'free_percent_crit':
+                    self._free_percent_crit = param.value
+
+        return SetParametersResult(successful=True)
+
+    def check_disk_usage(self, diag: DiagnosticStatus) -> DiagnosticStatus:
+        """Compute the disk usage and derive a status from it.
+
+        Task periodically ran by the diagnostic updater.
+        """
+        diag.level = DiagnosticStatus.OK
+
+        total, _, free = disk_usage(self._path)
+        percent = free / total
+
+        if percent > self._free_percent_low:
+            diag.level = DiagnosticStatus.OK
+        elif percent > self._free_percent_crit:
+            diag.level = DiagnosticStatus.WARN
+        else:
+            diag.level = DiagnosticStatus.ERROR
+
+        total_go = total // (1024 * 1024)
+        diag.values.extend(
+            [
+                KeyValue(key='Name', value=self._path),
+                KeyValue(key='Status', value=DICT_STATUS[diag.level]),
+                KeyValue(key='Total (Go)', value=str(total_go)),
+                KeyValue(key='Available (%)', value=str(round(percent, 2))),
+            ]
+        )
+
+        diag.message = DICT_USAGE[diag.level]
+        return diag
+
+
+def main(args=None):
+    """Run the HDMonitor class."""
+    rclpy.init(args=args)
+
+    node = HDMonitor()
+    try:
+        rclpy.spin(node)
+    except KeyboardInterrupt:
+        pass
+
+
+if __name__ == '__main__':
+    main()

diagnostic_common_diagnostics/mainpage.dox

@@ -5,6 +5,7 @@
 \b diagnostic_common_diagnostics contains a few common diagnostic nodes
 
 - cpu_monitor publishes diagnostic messages with the CPU usage of the system.
+- hd_monitor publishes diagnostic messages related to the available space on a given storage device.
 - ntp_monitor publishes diagnostic messages for how well the NTP time sync is working.
 - tf_monitor used to publish diagnostic messages reporting on the health of
 the TF tree. It is based on tfwtf. It is not ported to ROS2.

diagnostic_common_diagnostics/test/systemtest/test_hd_monitor_launchtest.py

@@ -0,0 +1,110 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+# Software License Agreement (BSD License)
+#
+# Copyright (c) 2023, Robert Bosch GmbH
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+#
+#  * Redistributions of source code must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+#  * Redistributions in binary form must reproduce the above
+#    copyright notice, this list of conditions and the following
+#    disclaimer in the documentation and/or other materials provided
+#    with the distribution.
+#  * Neither the name of the Willow Garage nor the names of its
+#    contributors may be used to endorse or promote products derived
+#    from this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+# FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+# COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+# BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+# LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+# ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+# POSSIBILITY OF SUCH DAMAGE.
+
+import unittest
+
+from diagnostic_msgs.msg import DiagnosticArray
+
+import launch
+
+import launch_ros
+
+import launch_testing
+
+from launch_testing_ros import WaitForTopics
+
+import pytest
+
+import rclpy
+
+
+@pytest.mark.launch_test
+def generate_test_description():
+    """Launch the hd_monitor node and return a launch description."""
+    return launch.LaunchDescription(
+        [
+            launch_ros.actions.Node(
+                package='diagnostic_common_diagnostics',
+                executable='hd_monitor.py',
+                name='hd_monitor',
+                output='screen',
+                parameters=[{'free_percent_low': 0.20, 'free_percent_crit': 0.05}],
+            ),
+            launch_testing.actions.ReadyToTest(),
+        ]
+    )
+
+
+class TestHDMonitor(unittest.TestCase):
+    """Test if the hd_monitor node is publishing diagnostics."""
+
+    def __init__(self, methodName: str = 'runTest') -> None:
+        super().__init__(methodName)
+        self.received_messages = []
+
+    def _received_message(self, msg):
+        self.received_messages.append(msg)
+
+    def _get_min_level(self):
+        levels = [
+            int.from_bytes(status.level, 'little')
+            for diag in self.received_messages
+            for status in diag.status
+        ]
+        if len(levels) == 0:
+            return -1
+        return min(levels)
+
+    def test_topic_published(self):
+        """Test if the hd_monitor node is publishing diagnostics."""
+        with WaitForTopics([('/diagnostics', DiagnosticArray)], timeout=5):
+            print('Topic found')
+
+        rclpy.init()
+        test_node = rclpy.create_node('test_node')
+        test_node.create_subscription(
+            DiagnosticArray, '/diagnostics', self._received_message, 1
+        )
+
+        while len(self.received_messages) < 10:
+            rclpy.spin_once(test_node, timeout_sec=1)
+            if (min_level := self._get_min_level()) == 0:
+                break
+
+        test_node.destroy_node()
+        rclpy.shutdown()
+        print(f'Got {len(self.received_messages)} messages:')
+        for msg in self.received_messages:
+            print(msg)
+        self.assertEqual(min_level, 0)