package_metadata.py

#!/usr/bin/env python
# -*- coding: utf-8 -*-

from __future__ import absolute_import, division, print_function, \
    with_statement, unicode_literals

import os
import sys
import re

package_file = os.path.join(
    os.path.dirname(__file__), "sqlalchemy_tree/__about__.py")
file_content = open(package_file, "rt").read()


class Package_Metadata(dict):
    __getattr__ = dict.__getitem__
    __setattr__ = dict.__setitem__

    attributes = [
        'title', 'package_name', 'author', 'description', 'email',
        'version', 'license', 'copyright'
    ]

    @staticmethod
    def get_attribute(attr, file_content):
        regex_expression = r"^__{0}__ = ['\"]([^'\"]*)['\"]".format(attr)
        mo = re.search(regex_expression, file_content, re.M)
        if mo:
            return mo.group(1)
        else:
            raise RuntimeError(
                "Unable to find version string in %s." % (package_file,))

    def refresh(self, attributes):

        file_content = open(self.package_file, "rt").read()

        for k in attributes:
            attr_val = self.get_attribute(k, file_content)
            if attr_val:
                self[k] = attr_val

    def __init__(self, package_file, attributes=None):

        if attributes:
            self.attributes = attributes

        self.package_file = package_file

        self.refresh(self.attributes)


p = Package_Metadata(package_file)


def print_metadata():
    for k, v in p.items():
        print('%s: %s' % (k, v))

if __name__ == '__main__':
    print_metadata()
    sys.exit()