parameters.py

from datetime import datetime
import os
import subprocess


def get_commandline_output(command):
    p = subprocess.Popen(command, stdout=subprocess.PIPE, shell=True)
    (stdout, stderr) = p.communicate()
    return stdout


def git_current_commit_hash():
    return get_commandline_output('git rev-parse HEAD').strip().decode('utf-8')


def git_uncommited_changes():
    res = get_commandline_output('git diff --name-only')
    return len(res) > 0


def try_convert_to_float(string):
    try:
        return float(string)
    except ValueError:
        return string


def parameters_from_file(filename):
    with open(filename, 'r') as file:
        lines = file.read().splitlines()
    parameters = {}
    for line_number, line in enumerate(lines):
        line = line.strip()
        comment_start = line.find('#')
        if comment_start >= 0:
            line = line[:comment_start]
        if len(line) == 0:
            continue

        if line.startswith('!include'):
            included_filename = line[len('!include '):]
            included_filename = os.path.join(os.path.dirname(filename), included_filename)
            parameters = {**parameters, **parameters_from_file(included_filename)}
        else:
            parts = line.split('=', 1)
            if len(parts) != 2:
                print('Invalid syntax in "{}" on line {}. Expected key = value (separated by single =).'.format(
                    filename, line_number + 1))
            key = parts[0].strip()
            value = parts[1].strip()
            if value.isdigit():
                value = int(value)
            else:
                value = try_convert_to_float(value)
            parameters[key] = value

    return parameters


def parameters_parse(filename):
    # TODO(simonhog): Error handling
    parameters = parameters_from_file(filename)

    now = datetime.now()
    parameters['__date'] = now.isoformat()  # TODO(simonhog): Ensure readable, add timezone. pytz library?
    parameters['__date_string'] = now.strftime('%Y%m%d_%H_%M_%S_%f')
    parameters['__parameter_file'] = os.path.abspath(filename)
    if parameters.get('development', 'false').lower() != 'true':
        parameters['__code_git_hash'] = git_current_commit_hash()
        if git_uncommited_changes():
            print("[WARN]: Uncommitted changes in git repository")
    if 'shortname' not in parameters:
        parameters['shortname'] = 'unnamed'
    return parameters


def parameters_save(parameters, output_directory):
    out_filename = os.path.join(output_directory, 'metadata.txt')
    del parameters['__date_string']
    with open(out_filename, 'w') as file:
        for key, value in parameters.items():
            file.write('{} = {}\n'.format(key, value))