history.py

from portality.core import app
from portality.dao import DomainObject
import os
import json

from portality.lib import dates
from portality.lib.dates import FMT_DATE_STD


class History(DomainObject):
    SAVE_BASE_DIRECTORY = os.path.join(app.config['ARTICLE_HISTORY_DIR'], '..')  # sensible default, but always override this in children

    def save(self):  # method signature intentionally kept different from base class to indicate you can't do the usual things on .save()
        self.__save_to_file()

    def __save_to_file(self):
        """
        Override usual DomainObject.save method so instead of sending
        to Elasticsearch, this will save objects in files on a daily
        directory basis. A new history object should be created every time
        when a new snapshot of an article or journal is needed - i.e.
        they are never changed and re-saved.

        With this implementation if a history object is changed and saved
        a 2nd time (after the initial save to put it on disk):
          - the file will be overwritten (if it saved 2+ times on the same
           day)
          OR
          - a new file will be created in a new directory (if the 2nd+ time
           it's saved is on a different day).
        """
        self.set_id(self.makeid())
        directory_name = dates.now_str(FMT_DATE_STD)
        full_dir = os.path.join(self.SAVE_BASE_DIRECTORY, directory_name)
        full_path = os.path.join(full_dir, "{0}.json".format(self.id))

        if not os.path.isdir(full_dir):
            os.makedirs(full_dir)

        with open(full_path, 'w') as o:
            o.write(json.dumps(self.data, indent=4))


class ArticleHistory(History):
    __type__ = "article_history"
    SAVE_BASE_DIRECTORY = app.config['ARTICLE_HISTORY_DIR']

class JournalHistory(History):
    __type__ = "journal_history"
    SAVE_BASE_DIRECTORY = app.config['JOURNAL_HISTORY_DIR']