Source code for vulyk.blueprints.gamification.core.parsing

# -*- coding: utf-8 -*-
"""
All available parsers, that convert raw representation could be received from
any external source, are and should be kept here.
"""
try:
    import ujson as json
except ImportError:
    import json

from .rules import Rule, ProjectRule


class RuleParsingException(Exception):
    """
    Basic exception for all types of rule parsing errors
    """
    pass


class RuleParser:
    """
    Just a stub in case if we want to extend parsing sources.
    """
    pass


class JsonRuleParser(RuleParser):
    """
    Basic JSON parser.
    """
    __slots__ = []

    @staticmethod
    def parse(json_string: str) -> Rule:
        """
        Actually perform parsing from JSON-encoded string to an actual rule.

        :param json_string: JSON dict with all the data about the achievement.
        :type json_string: str

        :returns: Fully parsed rule object.
        :rtype: Rule

        :exception: RuleParsingException
        """
        try:
            parsee = json.loads(json_string)
            name = parsee['name']
            task_type_name = parsee.get('task_type_name', '')
            hash_id = str(hash('{}{}'.format(name, task_type_name)))

            rule = Rule(rule_id=hash_id,
                        badge=parsee['badge'],
                        name=name,
                        description=parsee['description'],
                        bonus=int(parsee['bonus']),
                        tasks_number=int(parsee['tasks_number']),
                        days_number=int(parsee['days_number']),
                        is_weekend=bool(parsee['is_weekend']),
                        is_adjacent=bool(parsee['is_adjacent']))

            if task_type_name:
                return ProjectRule.from_rule(rule, task_type_name)
            else:
                return rule
        except ValueError:
            raise RuleParsingException('Can not parse {}'.format(json_string))
        except (TypeError, KeyError) as e:
            raise RuleParsingException('Invalid JSON passed: {}'.format(e))