debugtrace 1.2.0

Output trace logs when debugging Python programs

DebugTrace-py is a library that outputs trace logs when debugging your Python programs. It supports Python 3.7 or later. By embedding “_ = debugtrace.enter()” at the start of the method, you can output the execution status of the program under development.

1. Features

• Automatically outputs the method name, source file name and line number of invokers of debugtrace.enter function.

• Also outputs end logs when the scope ends.

• Indents logs automatically with nested methods and objects.

• Automatically line breaks in value output.

• Uses reflection to output content even for objects of classes that do not implement the __str__ method.

• You can customize output contents by setting debugtrace.ini file.

• You can select sys.stdout, sys.stderr or logging.Logger to output.

2. Install

pip install debugtrace

3. How to use

Do the following for the debug target and related functions and methods:

• Insert “_ = debugtrace.enter()” at the beginning of functions and methods.

• Insert “debugtrace.print('foo', foo)” to output variables to the log if necessary.

The following is an example of a Python program using DebugTrace-py and a log when it is executed.

# readme_example.py
import datetime
import debugtrace # TODO: Remove after debugging

# Contact class
class Contact(object):
    def __init__(self, id: int, firstName: str, lastName: str, birthday: datetime.date) -> None:
        _ = debugtrace.enter(self) # TODO: Remove after debugging
        self.id = id
        self.firstName = firstName
        self.lastName  = lastName
        self.birthday  = birthday

def func2():
    _ = debugtrace.enter() # TODO: Remove after debugging
    contact = [
        Contact(1, 'Akane' , 'Apple', datetime.date(1991, 2, 3)),
        Contact(2, 'Yukari', 'Apple', datetime.date(1992, 3, 4))
    ]
    debugtrace.print('contact', contact) # TODO: Remove after debugging

def func1():
    _ = debugtrace.enter() # TODO: Remove after debugging
    debugtrace.print('Hello, World!') # TODO: Remove after debugging
    func2()

func1()

Log output contents:

2022-08-15 13:19:11.080752 DebugTrace-py 1.2.0 on Python 3.10.4
2022-08-15 13:19:11.080803   config file path: <No config file>
2022-08-15 13:19:11.080834   logger: sys.stderr
2022-08-15 13:19:11.080901
2022-08-15 13:19:11.080926 ______________________________ MainThread #139879021757504 ______________________________
2022-08-15 13:19:11.080953
2022-08-15 13:19:11.081716 Enter func1 (readme_example.py:22)
2022-08-15 13:19:11.081791 | Hello, World! (readme_example.py:23)
2022-08-15 13:19:11.081853 | Enter func2 (readme_example.py:14)
2022-08-15 13:19:11.081919 | | Enter Contact.__init__ (readme_example.py:7)
2022-08-15 13:19:11.081964 | | Leave Contact.__init__ (readme_example.py:7) duration: 0:00:00.000010
2022-08-15 13:19:11.082032 | |
2022-08-15 13:19:11.082059 | | Enter Contact.__init__ (readme_example.py:7)
2022-08-15 13:19:11.082105 | | Leave Contact.__init__ (readme_example.py:7) duration: 0:00:00.000009
2022-08-15 13:19:11.082439 | |
2022-08-15 13:19:11.082467 | | contacts = [
2022-08-15 13:19:11.082498 | |   (__main__.Contact){
2022-08-15 13:19:11.082521 | |     birthday: 1991-02-03, firstName: 'Akane', id: 1, lastName: 'Apple'
2022-08-15 13:19:11.082543 | |   },
2022-08-15 13:19:11.082566 | |   (__main__.Contact){
2022-08-15 13:19:11.082595 | |     birthday: 1992-03-04, firstName: 'Yukari', id: 2, lastName: 'Apple'
2022-08-15 13:19:11.082618 | |   }
2022-08-15 13:19:11.082638 | | ] (readme_example.py:19)
2022-08-15 13:19:11.082651 | |
2022-08-15 13:19:11.082678 | Leave func2 (readme_example.py:14) duration: 0:00:00.000792
2022-08-15 13:19:11.082709 Leave func1 (readme_example.py:22) duration: 0:00:00.000957

4. Functions

There are mainly the following functions.

Function list

Name	Discription
enter	Outputs an entering log. Also outputs a leaving log at the end of the code block. Arguments: invoker (object optional): Pass the self or cls of the invoker. (Optional) Examples: _ = debugtrace.enter(self) _ = debugtrace.enter(cls) _ = debugtrace.enter()
print	Outputs the variable name and value. Arguments: name (str): Variable name, etc. value (object): Output value output_private (bool): Output private member if True (default: False) output_method (bool): Output method if True (default: False) The following are keyword arguments and can be omitted. force_reflection (bool): If true, outputs using reflection even if it has a __str__ or __repr__ method (default: False) output_private (bool): If true, also outputs private members when using reflection (default: False) output_method (bool): If true, also outputs method members when using reflection (default: False) collection_limit (int): The limit value of elements such as list, tuple and dict to output (default: None) bytes_limit (int): The limit value of elements for bytes and bytearray to output (default: None) string_limit (int): The limit value of characters for string to output (default: None) reflection_nest_limit (int): The The limit value for reflection nesting (default: None) Examples: debugtrace.print('Hellow') debugtrace.print('foo', foo) debugtrace.print('foo', foo, force_reflection=True) debugtrace.print('foos', foos, collection_limit=1024)

5. Options that can be specified in the debugtrace.ini file

DebugTrace-py reads the debugtrace.ini file in the current directory for initialization. The section is [debugtrace].

You can specify the following options in the debugtrace.ini file.

debugtrace.ini

Option Name	Description	Default Value
logger	The logger used by debugtrace Specifiable Values: stdout - Output to sys.stdout stderr - Output to sys.stderr logger - Output using logging package file: <log file path> - Output directly to the file	stderr
logging_config_file	The configuration file name specified in logging package	logging.conf
logging_logger_name	The logger name when using the logging package	debugtrace
logging_level	The log level when using the logging package Specifiable Values: CRITICAL ERROR WARNING INFO DEBUG NOTSET	DEBUG
is_enabled	Specifiable Values: False: Log output is disabled True: Log output is enabled	True
enter_format	The format string of log output when entering functions or methods {0}: The function or method name {1}: The file name {2}: The line number	Enter {0} ({1}:{2})
leave_format	The format string of log output when leaving functions or methods {0}: The function or method name {1}: The file name {2}: The line number {3}: The time from entering	Leave {0} ({1}:{2}) duration: {3}
thread_boundary_format	The format string of logging at threads boundary {0}: The thread name {1}: The thread ID	______________________________ {0} #{1} ______________________________
maximum_indents	The maximum number of indents	32
indent_string	The indentation string for code	|\s
data_indent_string	The indentation string for data	\s\s
limit_string	The string to represent that it has exceeded the limit	...
non_output_string	The string to be output instead of not outputting value (Currently unused)	...
cyclic_reference_string	The string to represent that the cyclic reference occurs	*** Cyclic Reference ***
varname_value_separator	The separator string between the variable name and value	\s=\s
key_value_separator	The separator string between the key and value of dictionary and between the attribute name and value	:\s
print_suffix_format	The format string of print method suffix	\s({1}:{2})
count_format	The format string of the number of elements such as list, tuple and dict	count:{}
minimum_output_count	The minimum value to output the number of elements such as list, tuple and dict	16 (since 1.2.0) 5 (until 1.1.0)
length_format	The format string of the length of string and bytes	length:{}
minimum_output_length	The minimum value to output the length of string and bytes	16 (since 1.2.0) 5 (until 1.1.0)
log_datetime_format	Log date and time format when logger is StdOut or StdErr (Currently not configurable)	%Y-%m-%d %H:%M:%S.%f
maximum_data_output_width	The maximum output width of data	70
bytes_count_in_line	The count in line of bytes	16
collection_limit	The limit value of elements such as list, tuple and dict to output	128 (since 1.2.0) 512 (until 1.1.0)
bytes_limit	The limit value of elements for bytes and bytearray to output	256 (since 1.2.0) 8192 (until 1.1.0)
string_limit	The limit value of characters for string to output	256 (since 1.2.0) 8192 (until 1.1.0)
reflection_nest_limit	The The limit value for reflection nesting	4

Converts \s to space.

6. License

MIT License (MIT)

7. Release notes

DebugTrace-py 1.2.0 - August 15, 2022

• Added the runtime Python version to the startup log.

• Changed to output a log that shows thread switching.

• Changed default values for the following properties.

Property Name	New Default Value	Old Default Value
minimum_output_count	16	5
minimum_output_length	16	5
collection_limit	128	512
string_limit	256	8192
bytes_limit	256	8192

DebugTrace-py 1.1.0 - November 28, 2021

• Fixed a bug that an error occurs when outputting an object of a class that implements __str__ or __repr__.

• Do not output tuple, set, dict data types.

  (1, 2, 3) ← (tuple)(1, 2, 3)

  (1,) ← (tuple)(1)

  () ← (tuple)()

  {1, 2, 3} ← (set){1, 2, 3}

  {} ← (set){}

  {1: 'A', 2: 'B', 3; 'C'} ← (dict){1: 'A', 2: 'B', 3; 'C'}

  {:} ← (dict){}

DebugTrace-py 1.0.3 - August 12, 2021

• Improved the line break handling of data output

DebugTrace-py 1.0.2 - November 29, 2020

• Change the start message. ('DebugTrace-py ...' <- 'DebugTrace-python ...')

DebugTrace-py 1.0.1 - July 19, 2020

• Improved the line break handling of data output.

DebugTrace-py 1.0.0 - May 26, 2020

• First release

(C) 2020 Masato Kokubo