Helper functions to dump and load system information -- Enhances reproducibility of a scientific computing environment

sys_info_helper.py

"""
Helper functions to dump and load system information

Enhances reproducibility of a scientific computing environment

License: http://creativecommons.org/publicdomain/zero/1.0/

To the extent possible under law, the author has waived all copyright and
related or neighboring rights to this work.
This work is published from: Germany.
"""

from __future__ import unicode_literals
from builtins import str

import json
import os
import socket
import sys
import time
import uuid

import pip


def get_float_info():
    float_info = str(sys.float_info)
    items = float_info[float_info.find('(') + 1:].rstrip(')').split()
    return {
        key: value
        for key, value in [
            item.rstrip(',').split('=')
            for item in items
        ]
    }


def get_sys_info():
    return {
        'os': os.name,
        'environ': dict(os.environ),
        'argv': sys.argv,
        'timestamp': int(time.time()),
        'hostname': socket.gethostname(),
        'platform': sys.platform,
        'float_info': get_float_info(),
        'python': {
            'version': sys.version,
            'executable': sys.executable,
            'version_info': sys.version_info,
            'prefix': sys.prefix,
        },
        'packages': {
            package.key: package.version
            for package in pip.get_installed_distributions()
        },
        'uuid': str(uuid.uuid4()),
        '_json_dumps': (
            'environ',
            'argv',
            'float_info',
            'python',
            'packages',
        ),
    }


def dump_sys_info(target, sys_info=None):
    """
    Write the system information to a target with dict-like access structure

    E.g. via the ``attrs`` proxy object of a HDF5 file or group object
    """
    if sys_info is None:
        sys_info = get_sys_info()

    for key, value in sys_info.items():
        target[key] = (
            json.dumps(value)
            if key == '_json_dumps' or key in sys_info['_json_dumps']
            else value
        )

    return target


def load_sys_info(source):
    """
    Load the system information from a source with dict-like access structure

    E.g. via the ``attrs`` proxy object of a HDF5 file or group object
    """
    ret = dict(source)

    ret['_json_dumps'] = json.loads(ret['_json_dumps'])

    for key in ret['_json_dumps']:
        ret[key] = json.loads(ret[key])

    return ret


class Timer:
    """
    Helper class to time script execution

    See https://www.python.org/dev/peps/pep-0418/
    """

    times = ('process_time', 'perf_counter', 'time')

    def __init__(self):
        self.timer = dict()
        for my_time in self.times:
            self.timer[my_time] = dict()

    def start(self):
        for my_time in self.times:
            self.timer[my_time]['start'] = getattr(time, my_time)()

    def stop(self):
        for my_time in self.times:
            self.timer[my_time]['stop'] = getattr(time, my_time)()

    def get_times(self):
        ret = {
            my_time: self.timer[my_time]['stop'] - self.timer[my_time]['start']
            for my_time in self.times
        }
        ret['start_timestamp'] = int(self.timer['time']['start'])
        ret['stop_timestamp'] = int(self.timer['time']['stop'])
        return ret

    def dump_times(self, target, my_times=None):
        """
        Write the times to a target with dict-like access structure

        E.g. via the ``attrs`` proxy object of a HDF5 file or group object
        """
        if my_times is None:
            my_times = self.get_times()

        for key, value in my_times.items():
            target[key] = value

        return target