Memory Statistics Config and Show Commands (#3575)

What I did
Provided support for the configuration and show commands of memory statistics feature.

How I did it
I added a new config file config/memory_statistics.py for the configuration commands of memory statistics feature.
Added a show file show/memory_statistics.py for the show commands of memory statistics feature.
Added a test file tests/memory_statistics_test.py to test the config and show commands of memory statistics feature

How to verify it
Cli support for config and show file is available

Author: kanza-latif

config/memory_statistics.py

@@ -0,0 +1,331 @@
+# Standard library imports
+import syslog
+
+# Third-party imports
+import click
+
+# Type hints
+from typing import Tuple, Optional
+
+# Local imports
+from swsscommon.swsscommon import ConfigDBConnector
+
+# Constants
+MEMORY_STATISTICS_TABLE = "MEMORY_STATISTICS"
+MEMORY_STATISTICS_KEY = "memory_statistics"
+
+SAMPLING_INTERVAL_MIN = 3
+SAMPLING_INTERVAL_MAX = 15
+RETENTION_PERIOD_MIN = 1
+RETENTION_PERIOD_MAX = 30
+
+DEFAULT_SAMPLING_INTERVAL = 5  # minutes
+DEFAULT_RETENTION_PERIOD = 15  # days
+
+syslog.openlog("memory_statistics_config", syslog.LOG_PID | syslog.LOG_CONS, syslog.LOG_USER)
+
+
+def log_to_syslog(message: str, level: int = syslog.LOG_INFO) -> None:
+    """
+    Logs a message to the system log (syslog) with error handling.
+
+    This function logs the provided message to syslog at the specified level.
+    It handles potential errors such as system-related issues (OSError) and
+    invalid parameters (ValueError) by displaying appropriate error messages.
+
+    Args:
+        message (str): The message to log.
+        level (int, optional): The log level (default is syslog.LOG_INFO).
+    """
+    try:
+        syslog.syslog(level, message)
+    except OSError as e:
+        click.echo(f"System error while logging to syslog: {e}", err=True)
+    except ValueError as e:
+        click.echo(f"Invalid syslog parameters: {e}", err=True)
+
+
+def generate_error_message(error_type: str, error: Exception) -> str:
+    """
+    Generates a formatted error message for logging and user feedback.
+
+    Args:
+        error_type (str): A short description of the error type.
+        error (Exception): The actual exception object.
+
+    Returns:
+        str: A formatted error message string.
+    """
+    return f"{error_type}: {error}"
+
+
+def validate_range(value: int, min_val: int, max_val: int) -> bool:
+    """
+    Validates whether a given integer value falls within a specified range.
+
+    Args:
+        value (int): The value to validate.
+        min_val (int): The minimum allowable value.
+        max_val (int): The maximum allowable value.
+
+    Returns:
+        bool: True if the value is within range, False otherwise.
+    """
+    return min_val <= value <= max_val
+
+
+class MemoryStatisticsDB:
+    """
+    Singleton class for managing the connection to the memory statistics configuration database.
+    """
+    _instance = None
+    _db = None
+
+    def __new__(cls):
+        """
+        Creates and returns a singleton instance of MemoryStatisticsDB.
+
+        Returns:
+            MemoryStatisticsDB: The singleton instance.
+        """
+        if cls._instance is None:
+            cls._instance = super(MemoryStatisticsDB, cls).__new__(cls)
+            cls._connect_db()
+        return cls._instance
+
+    @classmethod
+    def _connect_db(cls):
+        """
+        Establishes a connection to the ConfigDB database.
+
+        Logs an error if the connection fails.
+        """
+        try:
+            cls._db = ConfigDBConnector()
+            cls._db.connect()
+        except RuntimeError as e:
+            log_to_syslog(f"ConfigDB connection failed: {e}", syslog.LOG_ERR)
+            cls._db = None
+
+    @classmethod
+    def get_db(cls):
+        """
+        Retrieves the database connection instance, reconnecting if necessary.
+
+        Returns:
+            ConfigDBConnector: The active database connection.
+
+        Raises:
+            RuntimeError: If the database connection is unavailable.
+        """
+        if cls._db is None:
+            cls._connect_db()
+        if cls._db is None:
+            raise RuntimeError("Database connection unavailable")
+        return cls._db
+
+
+def update_memory_statistics_status(enabled: bool) -> Tuple[bool, Optional[str]]:
+    """
+    Updates the enable/disable status of memory statistics in the configuration database.
+
+    This function modifies the configuration database to enable or disable
+    memory statistics collection based on the provided status. It also logs
+    the action and returns a tuple indicating whether the operation was successful.
+
+    Args:
+        enabled (bool): True to enable memory statistics, False to disable.
+
+    Returns:
+        Tuple[bool, Optional[str]]: A tuple containing success status and an optional error message.
+    """
+    try:
+        db = MemoryStatisticsDB.get_db()
+
+        db.mod_entry(MEMORY_STATISTICS_TABLE, MEMORY_STATISTICS_KEY, {"enabled": str(enabled).lower()})
+        msg = f"Memory statistics feature {'enabled' if enabled else 'disabled'} successfully."
+        click.echo(msg)
+        log_to_syslog(msg)
+        return True, None
+    except (KeyError, ConnectionError, RuntimeError) as e:
+        error_msg = generate_error_message(f"Failed to {'enable' if enabled else 'disable'} memory statistics", e)
+
+        click.echo(error_msg, err=True)
+        log_to_syslog(error_msg, syslog.LOG_ERR)
+        return False, error_msg
+
+
+@click.group(help="Tool to manage memory statistics configuration.")
+def cli():
+    """
+    Memory statistics configuration tool.
+
+    This command-line interface (CLI) allows users to configure and manage
+    memory statistics settings such as enabling/disabling the feature and
+    modifying parameters like the sampling interval and retention period.
+    """
+    pass
+
+
+@cli.group(help="Commands to configure system settings.")
+def config():
+    """
+    Configuration commands for managing memory statistics.
+
+    Example:
+        $ config memory-stats enable
+        $ config memory-stats sampling-interval 5
+    """
+    pass
+
+
+@config.group(name='memory-stats', help="Manage memory statistics collection settings.")
+def memory_stats():
+    """Configure memory statistics collection and settings.
+
+    This group contains commands to enable/disable memory statistics collection
+    and configure related parameters.
+
+    Examples:
+        Enable memory statistics:
+        $ config memory-stats enable
+
+        Set sampling interval to 5 minutes:
+        $ config memory-stats sampling-interval 5
+
+        Set retention period to 7 days:
+        $ config memory-stats retention-period 7
+
+        Disable memory statistics:
+        $ config memory-stats disable
+    """
+    pass
+
+
+@memory_stats.command(name='enable')
+def memory_stats_enable():
+    """Enable memory statistics collection.
+
+    This command enables the collection of memory statistics on the device.
+    It updates the configuration and reminds the user to run 'config save'
+    to persist changes.
+
+    Example:
+        $ config memory-stats enable
+        Memory statistics feature enabled successfully.
+        Reminder: Please run 'config save' to persist changes.
+    """
+    success, error = update_memory_statistics_status(True)
+    if success:
+        click.echo("Reminder: Please run 'config save' to persist changes.")
+        log_to_syslog("Memory statistics enabled. Reminder to run 'config save'")
+
+
+@memory_stats.command(name='disable')
+def memory_stats_disable():
+    """Disable memory statistics collection.
+
+    This command disables the collection of memory statistics on the device.
+    It updates the configuration and reminds the user to run 'config save'
+    to persist changes.
+
+    Example:
+        $ config memory-stats disable
+        Memory statistics feature disabled successfully.
+        Reminder: Please run 'config save' to persist changes.
+    """
+    success, error = update_memory_statistics_status(False)
+    if success:
+        click.echo("Reminder: Please run 'config save' to persist changes.")
+        log_to_syslog("Memory statistics disabled. Reminder to run 'config save'")
+
+
+@memory_stats.command(name='sampling-interval')
+@click.argument("interval", type=int)
+def memory_stats_sampling_interval(interval: int):
+    """
+    Configure the sampling interval for memory statistics collection.
+
+    This command updates the interval at which memory statistics are collected.
+    The interval must be between 3 and 15 minutes.
+
+    Args:
+        interval (int): The desired sampling interval in minutes.
+
+    Examples:
+        Set sampling interval to 5 minutes:
+        $ config memory-stats sampling-interval 5
+        Sampling interval set to 5 minutes successfully.
+        Reminder: Please run 'config save' to persist changes.
+
+        Invalid interval example:
+        $ config memory-stats sampling-interval 20
+        Error: Sampling interval must be between 3 and 15 minutes.
+    """
+    if not validate_range(interval, SAMPLING_INTERVAL_MIN, SAMPLING_INTERVAL_MAX):
+        error_msg = f"Error: Sampling interval must be between {SAMPLING_INTERVAL_MIN} and {SAMPLING_INTERVAL_MAX}."
+        click.echo(error_msg, err=True)
+        log_to_syslog(error_msg, syslog.LOG_ERR)
+        return
+
+    try:
+        db = MemoryStatisticsDB.get_db()
+        db.mod_entry(MEMORY_STATISTICS_TABLE, MEMORY_STATISTICS_KEY, {"sampling_interval": str(interval)})
+        success_msg = f"Sampling interval set to {interval} minutes successfully."
+        click.echo(success_msg)
+        log_to_syslog(success_msg)
+        click.echo("Reminder: Please run 'config save' to persist changes.")
+    except (KeyError, ConnectionError, ValueError, RuntimeError) as e:
+        error_msg = generate_error_message(f"{type(e).__name__} setting sampling interval", e)
+        click.echo(error_msg, err=True)
+        log_to_syslog(error_msg, syslog.LOG_ERR)
+        return
+
+
+@memory_stats.command(name='retention-period')
+@click.argument("period", type=int)
+def memory_stats_retention_period(period: int):
+    """
+    Configure the retention period for memory statistics storage.
+
+    This command sets the number of days memory statistics should be retained.
+    The retention period must be between 1 and 30 days.
+
+    Args:
+        period (int): The desired retention period in days.
+
+    Examples:
+        Set retention period to 7 days:
+        $ config memory-stats retention-period 7
+        Retention period set to 7 days successfully.
+        Reminder: Please run 'config save' to persist changes.
+
+        Invalid period example:
+        $ config memory-stats retention-period 45
+        Error: Retention period must be between 1 and 30 days.
+    """
+    if not validate_range(period, RETENTION_PERIOD_MIN, RETENTION_PERIOD_MAX):
+        error_msg = f"Error: Retention period must be between {RETENTION_PERIOD_MIN} and {RETENTION_PERIOD_MAX}."
+        click.echo(error_msg, err=True)
+        log_to_syslog(error_msg, syslog.LOG_ERR)
+        return
+
+    try:
+        db = MemoryStatisticsDB.get_db()
+        db.mod_entry(MEMORY_STATISTICS_TABLE, MEMORY_STATISTICS_KEY, {"retention_period": str(period)})
+        success_msg = f"Retention period set to {period} days successfully."
+        click.echo(success_msg)
+        log_to_syslog(success_msg)
+        click.echo("Reminder: Please run 'config save' to persist changes.")
+    except (KeyError, ConnectionError, ValueError, RuntimeError) as e:
+        error_msg = generate_error_message(f"{type(e).__name__} setting retention period", e)
+        click.echo(error_msg, err=True)
+        log_to_syslog(error_msg, syslog.LOG_ERR)
+        return
+
+
+if __name__ == "__main__":
+    try:
+        cli()
+    finally:
+        syslog.closelog()