.. default-domain:: chpl

.. module:: Logging

Logging
=======
**Usage**

.. code-block:: chapel

   use Logging;


or

.. code-block:: chapel

   import Logging;

.. enum:: enum LogLevel { DEBUG, INFO, WARN, ERROR, CRITICAL }

   
   * The LogLevel enum is used to provide a strongly-typed means of
   * configuring the logging level of a Logger object
   

   .. enumconstant:: enum constant DEBUG

   .. enumconstant:: enum constant INFO

   .. enumconstant:: enum constant WARN

   .. enumconstant:: enum constant ERROR

   .. enumconstant:: enum constant CRITICAL

.. enum:: enum LogChannel { CONSOLE, FILE }

   
   * The LogChannel enum is used to provide a strongly-typed means of
   * configuring the channel such as stdout or file where log messages
   * are written.
   

   .. enumconstant:: enum constant CONSOLE

   .. enumconstant:: enum constant FILE

.. class:: OutputHandler

   
   * The OutputHandler class defines the interface for all derived 
   * classes that write log messages to various channels.
   

   .. method:: proc write(message: string) throws

.. class:: ConsoleOutputHandler : OutputHandler

   
   * The ConsoleOutputHandler writes log messages to the Arkouda console.
   

   .. method:: override proc write(message: string) throws

.. class:: FileOutputHandler : OutputHandler

   
   * The FileOutputHandler writes log messages to the configured filePath.
   

   .. attribute:: var filePath: string

   .. method:: proc init(filePath: string)

   .. method:: override proc write(message: string) throws

   .. method:: proc writeToFile(filePath: string, line: string) throws

      
      * Writes to file, creating file if it does not exist
      

.. function:: proc getOutputHandler(channel: LogChannel): owned OutputHandler throws

   
   * getOutputHandler is a factory method for OutputHandler implementations.
   

.. class:: Logger

   
   * The Logger class provides structured log messages at various levels
   * of logging sensitivity analogous to other languages such as Python.
   

   .. attribute:: var level: LogLevel = LogLevel.INFO

   .. attribute:: var warnLevels = new set(LogLevel, [LogLevel.WARN, LogLevel.INFO, LogLevel.DEBUG])

   .. attribute:: var criticalLevels = new set(LogLevel, [LogLevel.CRITICAL, LogLevel.WARN, LogLevel.INFO, LogLevel.DEBUG])

   .. attribute:: var errorLevels = new set(LogLevel, [LogLevel.ERROR, LogLevel.CRITICAL, LogLevel.WARN, LogLevel.INFO, LogLevel.DEBUG])

   .. attribute:: var infoLevels = new set(LogLevel, [LogLevel.INFO, LogLevel.DEBUG])

   .. attribute:: var printDate: bool = true

   .. attribute:: var outputHandler: owned OutputHandler = try! getOutputHandler(LogChannel.CONSOLE)

   .. method:: proc init()

   .. method:: proc init(level: LogLevel)

   .. method:: proc init(level: LogLevel, channel: LogChannel)

   .. method:: proc debug(moduleName, routineName, lineNumber, msg: string) throws

   .. method:: proc info(moduleName, routineName, lineNumber, msg: string) throws

   .. method:: proc warn(moduleName, routineName, lineNumber, msg: string) throws

   .. method:: proc critical(moduleName, routineName, lineNumber, msg: string) throws

   .. method:: proc error(moduleName, routineName, lineNumber, msg: string) throws

   .. method:: proc generateErrorMsg(moduleName: string, routineName, lineNumber, error) throws

   .. method:: proc generateLogMessage(moduleName: string, routineName, lineNumber, msg, level: string) throws

   .. method:: proc generateDateTimeString() throws